The specific failure of a normally responsive individual to make an immune response to a known antigen. It results from previous contact with the antigen by an immunologically immature individual (fetus or neonate) or by an adult exposed to extreme high-dose or low-dose antigen, or by exposure to radiation, antimetabolites, antilymphocytic serum, etc.
Progressive diminution of the susceptibility of a human or animal to the effects of a drug, resulting from its continued administration. It should be differentiated from DRUG RESISTANCE wherein an organism, disease, or tissue fails to respond to the intended effectiveness of a chemical or drug. It should also be differentiated from MAXIMUM TOLERATED DOSE and NO-OBSERVED-ADVERSE-EFFECT LEVEL.
The body's defense mechanism against foreign organisms or substances and deviant native cells. It includes the humoral immune response and the cell-mediated response and consists of a complex of interrelated cellular, molecular, and genetic components.
An induced state of non-reactivity to grafted tissue from a donor organism that would ordinarily trigger a cell-mediated or humoral immune response.
CD4-positive T cells that inhibit immunopathology or autoimmune disease in vivo. They inhibit the immune response by influencing the activity of other cell types. Regulatory T-cells include naturally occurring CD4+CD25+ cells, IL-10 secreting Tr1 cells, and Th3 cells.
The normal lack of the ability to produce an immunological response to autologous (self) antigens. A breakdown of self tolerance leads to autoimmune diseases. The ability to recognize the difference between self and non-self is the prime function of the immune system.
Inbred C57BL mice are a strain of laboratory mice that have been produced by many generations of brother-sister matings, resulting in a high degree of genetic uniformity and homozygosity, making them widely used for biomedical research, including studies on genetics, immunology, cancer, and neuroscience.
A test to determine the ability of an individual to maintain HOMEOSTASIS of BLOOD GLUCOSE. It includes measuring blood glucose levels in a fasting state, and at prescribed intervals before and after oral glucose intake (75 or 100 g) or intravenous infusion (0.5 g/kg).
Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.
Process whereby the immune system reacts against the body's own tissues. Autoimmunity may produce or be caused by AUTOIMMUNE DISEASES.
Specialized cells of the hematopoietic system that have branch-like extensions. They are found throughout the lymphatic system, and in non-lymphoid tissues such as SKIN and the epithelia of the intestinal, respiratory, and reproductive tracts. They trap and process ANTIGENS, and present them to T-CELLS, thereby stimulating CELL-MEDIATED IMMUNITY. They are different from the non-hematopoietic FOLLICULAR DENDRITIC CELLS, which have a similar morphology and immune system function, but with respect to humoral immunity (ANTIBODY PRODUCTION).
The classic hemophilia resulting from a deficiency of factor VIII. It is an inherited disorder of blood coagulation characterized by a permanent tendency to hemorrhage.
Inbred BALB/c mice are a strain of laboratory mice that have been selectively bred to be genetically identical to each other, making them useful for scientific research and experiments due to their consistent genetic background and predictable responses to various stimuli or treatments.
Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.
A dioxygenase with specificity for the oxidation of the indoleamine ring of TRYPTOPHAN. It is an extrahepatic enzyme that plays a role in metabolism as the first and rate limiting enzyme in the kynurenine pathway of TRYPTOPHAN catabolism.
A subclass of winged helix DNA-binding proteins that share homology with their founding member fork head protein, Drosophila.
Endogenous tissue constituents that have the ability to interact with AUTOANTIBODIES and cause an immune response.
Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.
Disorders that are characterized by the production of antibodies that react with host tissues or immune effector cells that are autoreactive to endogenous peptides.
A critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.
Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.
The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from the presence of naturally occurring ANTI-INFECTIVE AGENTS, constitutional factors such as BODY TEMPERATURE and immediate acting immune cells such as NATURAL KILLER CELLS.
A low affinity interleukin-2 receptor subunit that combines with the INTERLEUKIN-2 RECEPTOR BETA SUBUNIT and the INTERLEUKIN RECEPTOR COMMON GAMMA-CHAIN to form a high affinity receptor for INTERLEUKIN-2.
Blood-coagulation factor VIII. Antihemophilic factor that is part of the factor VIII/von Willebrand factor complex. Factor VIII is produced in the liver and acts in the intrinsic pathway of blood coagulation. It serves as a cofactor in factor X activation and this action is markedly enhanced by small amounts of thrombin.
An encapsulated lymphatic organ through which venous blood filters.
Manipulation of the host's immune system in treatment of disease. It includes both active and passive immunization as well as immunosuppressive therapy to prevent graft rejection.
Deliberate prevention or diminution of the host's immune response. It may be nonspecific as in the administration of immunosuppressive agents (drugs or radiation) or by lymphocyte depletion or may be specific as in desensitization or the simultaneous administration of antigen and immunosuppressive drugs.
Form of passive immunization where previously sensitized immunologic agents (cells or serum) are transferred to non-immune recipients. When transfer of cells is used as a therapy for the treatment of neoplasms, it is called adoptive immunotherapy (IMMUNOTHERAPY, ADOPTIVE).
Manifestations of the immune response which are mediated by antigen-sensitized T-lymphocytes via lymphokines or direct cytotoxicity. This takes place in the absence of circulating antibody or where antibody plays a subordinate role.
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
Disorders caused by abnormal or absent immunologic mechanisms, whether humoral, cell-mediated, or both.
A cytokine produced by a variety of cell types, including T-LYMPHOCYTES; MONOCYTES; DENDRITIC CELLS; and EPITHELIAL CELLS that exerts a variety of effects on immunoregulation and INFLAMMATION. Interleukin-10 combines with itself to form a homodimeric molecule that is the biologically active form of the protein.
Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.
Vaccines or candidate vaccines designed to prevent or treat cancer. Vaccines are produced using the patient's own whole tumor cells as the source of antigens, or using tumor-specific antigens, often recombinantly produced.
Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.
Substances that are recognized by the immune system and induce an immune reaction.
The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.
Protection from an infectious disease agent that is mediated by B- and T- LYMPHOCYTES following exposure to specific antigen, and characterized by IMMUNOLOGIC MEMORY. It can result from either previous infection with that agent or vaccination (IMMUNITY, ACTIVE), or transfer of antibody or lymphocytes from an immune donor (IMMUNIZATION, PASSIVE).
The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
The major interferon produced by mitogenically or antigenically stimulated LYMPHOCYTES. It is structurally different from TYPE I INTERFERON and its major activity is immunoregulation. It has been implicated in the expression of CLASS II HISTOCOMPATIBILITY ANTIGENS in cells that do not normally produce them, leading to AUTOIMMUNE DISEASES.
A classification of T-lymphocytes, especially into helper/inducer, suppressor/effector, and cytotoxic subsets, based on structurally or functionally different populations of cells.
Class I human histocompatibility (HLA) surface antigens encoded by alleles on locus B of the HLA complex. The HLA-G antigens are considered non-classical class I antigens due to their distinct tissue distribution which differs from HLA-A; HLA-B; and HLA-C antigens. Note that several isoforms of HLA-G antigens result from alternative splicing of messenger RNAs produced from the HLA-G*01 allele.
Functional inactivation of T- or B-lymphocytes rendering them incapable of eliciting an immune response to antigen. This occurs through different mechanisms in the two kinds of lymphocytes and can contribute to SELF TOLERANCE.
The grafting of skin in humans or animals from one site to another to replace a lost portion of the body surface skin.
Antibodies that react with self-antigens (AUTOANTIGENS) of the organism that produced them.
The occurrence in an individual of two or more cell populations of different chromosomal constitutions, derived from different individuals. This contrasts with MOSAICISM in which the different cell populations are derived from a single individual.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
Deliberate stimulation of the host's immune response. ACTIVE IMMUNIZATION involves administration of ANTIGENS or IMMUNOLOGIC ADJUVANTS. PASSIVE IMMUNIZATION involves administration of IMMUNE SERA or LYMPHOCYTES or their extracts (e.g., transfer factor, immune RNA) or transplantation of immunocompetent cell producing tissue (thymus or bone marrow).
An albumin obtained from the white of eggs. It is a member of the serpin superfamily.
A heterogeneous group of immunocompetent cells that mediate the cellular immune response by processing and presenting antigens to the T-cells. Traditional antigen-presenting cells include MACROPHAGES; DENDRITIC CELLS; LANGERHANS CELLS; and B-LYMPHOCYTES. FOLLICULAR DENDRITIC CELLS are not traditional antigen-presenting cells, but because they hold antigen on their cell surface in the form of IMMUNE COMPLEXES for B-cell recognition they are considered so by some authors.
Alteration of the immune system or of an immune response by agents that activate or suppress its function. This can include IMMUNIZATION or administration of immunomodulatory drugs. Immunomodulation can also encompass non-therapeutic alteration of the immune system effected by endogenous or exogenous substances.
Antigens stimulating the formation of, or combining with heterophile antibodies. They are cross-reacting antigens found in phylogenetically unrelated species.
Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.
Storage-stable blood coagulation factor acting in the intrinsic pathway. Its activated form, IXa, forms a complex with factor VIII and calcium on platelet factor 3 to activate factor X to Xa. Deficiency of factor IX results in HEMOPHILIA B (Christmas Disease).
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Removal, via CELL DEATH, of immature lymphocytes that interact with antigens during maturation. For T-lymphocytes this occurs in the thymus and ensures that mature T-lymphocytes are self tolerant. B-lymphocytes may also undergo clonal deletion.
Transplantation of tissue typical of one area to a different recipient site. The tissue may be autologous, heterologous, or homologous.
A single, unpaired primary lymphoid organ situated in the MEDIASTINUM, extending superiorly into the neck to the lower edge of the THYROID GLAND and inferiorly to the fourth costal cartilage. It is necessary for normal development of immunologic function early in life. By puberty, it begins to involute and much of the tissue is replaced by fat.
The transfer of leukocytes from a donor to a recipient or reinfusion to the donor.
A strain of non-obese diabetic mice developed in Japan that has been widely studied as a model for T-cell-dependent autoimmune insulin-dependent diabetes mellitus in which insulitis is a major histopathologic feature, and in which genetic susceptibility is strongly MHC-linked.
An immune response with both cellular and humoral components, directed against an allogeneic transplant, whose tissue antigens are not compatible with those of the recipient.
An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.
Theoretical representations that simulate the behavior or activity of immune system, processes, or phenomena. They include the use of mathematical equations, computers, and other electrical equipment.
Recombinant DNA vectors encoding antigens administered for the prevention or treatment of disease. The host cells take up the DNA, express the antigen, and present it to the immune system in a manner similar to that which would occur during natural infection. This induces humoral and cellular immune responses against the encoded antigens. The vector is called naked DNA because there is no need for complex formulations or delivery agents; the plasmid is injected in saline or other buffers.
A subtype of DIABETES MELLITUS that is characterized by INSULIN deficiency. It is manifested by the sudden onset of severe HYPERGLYCEMIA, rapid progression to DIABETIC KETOACIDOSIS, and DEATH unless treated with insulin. The disease may occur at any age, but is most common in childhood or adolescence.
Methods used by pathogenic organisms to evade a host's immune system.
Elements of limited time intervals, contributing to particular results or situations.
An increased reactivity to specific antigens mediated not by antibodies but by cells.
An organism that, as a result of transplantation of donor tissue or cells, consists of two or more cell lines descended from at least two zygotes. This state may result in the induction of donor-specific TRANSPLANTATION TOLERANCE.
The process by which antigen is presented to lymphocytes in a form they can recognize. This is performed by antigen presenting cells (APCs). Some antigens require processing before they can be recognized. Antigen processing consists of ingestion and partial digestion of the antigen by the APC, followed by presentation of fragments on the cell surface. (From Rosen et al., Dictionary of Immunology, 1989)
A critical subpopulation of regulatory T-lymphocytes involved in MHC Class I-restricted interactions. They include both cytotoxic T-lymphocytes (T-LYMPHOCYTES, CYTOTOXIC) and CD8+ suppressor T-lymphocytes.
Transplantation between individuals of the same species. Usually refers to genetically disparate individuals in contradistinction to isogeneic transplantation for genetically identical individuals.
Subset of helper-inducer T-lymphocytes which synthesize and secrete interleukin-2, gamma-interferon, and interleukin-12. Due to their ability to kill antigen-presenting cells and their lymphokine-mediated effector activity, Th1 cells are associated with vigorous delayed-type hypersensitivity reactions.
Serum that contains antibodies. It is obtained from an animal that has been immunized either by ANTIGEN injection or infection with microorganisms containing the antigen.
The complex formed by the binding of antigen and antibody molecules. The deposition of large antigen-antibody complexes leading to tissue damage causes IMMUNE COMPLEX DISEASES.
Nonsusceptibility to the pathogenic effects of foreign microorganisms or antigenic substances as a result of antibody secretions of the mucous membranes. Mucosal epithelia in the gastrointestinal, respiratory, and reproductive tracts produce a form of IgA (IMMUNOGLOBULIN A, SECRETORY) that serves to protect these ports of entry into the body.
The survival of a graft in a host, the factors responsible for the survival and the changes occurring within the graft during growth in the host.
A pathological process characterized by injury or destruction of tissues caused by a variety of cytologic and chemical reactions. It is usually manifested by typical signs of pain, heat, redness, swelling, and loss of function.
They are oval or bean shaped bodies (1 - 30 mm in diameter) located along the lymphatic system.
Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).
Immunosuppression by the administration of increasing doses of antigen. Though the exact mechanism is not clear, the therapy results in an increase in serum levels of allergen-specific IMMUNOGLOBULIN G, suppression of specific IgE, and an increase in suppressor T-cell activity.
Antigens that exist in alternative (allelic) forms in a single species. When an isoantigen is encountered by species members who lack it, an immune response is induced. Typical isoantigens are the BLOOD GROUP ANTIGENS.
The ability of tumors to evade destruction by the IMMUNE SYSTEM. Theories concerning possible mechanisms by which this takes place involve both cellular immunity (IMMUNITY, CELLULAR) and humoral immunity (ANTIBODY FORMATION), and also costimulatory pathways related to CD28 antigens (ANTIGENS, CD28) and CD80 antigens (ANTIGENS, CD80).
All of the processes involved in increasing CELL NUMBER including CELL DIVISION.
Inbred C3H mice are a strain of laboratory mice that have been selectively bred to maintain a high degree of genetic uniformity and share specific genetic characteristics, including susceptibility to certain diseases, which makes them valuable for biomedical research purposes.
Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.
A pathological state in which BLOOD GLUCOSE level is less than approximately 140 mg/100 ml of PLASMA at fasting, and above approximately 200 mg/100 ml plasma at 30-, 60-, or 90-minute during a GLUCOSE TOLERANCE TEST. This condition is seen frequently in DIABETES MELLITUS, but also occurs with other diseases and MALNUTRITION.
The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.
An inhibitory T CELL receptor that is closely related to CD28 ANTIGEN. It has specificity for CD80 ANTIGEN and CD86 ANTIGEN and acts as a negative regulator of peripheral T cell function. CTLA-4 antigen is believed to play role in inducing PERIPHERAL TOLERANCE.
Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.
A general term for the complex phenomena involved in allo- and xenograft rejection by a host and graft vs host reaction. Although the reactions involved in transplantation immunology are primarily thymus-dependent phenomena of cellular immunity, humoral factors also play a part in late rejection.
Nonsusceptibility to the invasive or pathogenic effects of foreign microorganisms or to the toxic effect of antigenic substances.
Sites on an antigen that interact with specific antibodies.
The transference of a heart from one human or animal to another.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Agents that suppress immune function by one of several mechanisms of action. Classical cytotoxic immunosuppressants act by inhibiting DNA synthesis. Others may act through activation of T-CELLS or by inhibiting the activation of HELPER CELLS. While immunosuppression has been brought about in the past primarily to prevent rejection of transplanted organs, new applications involving mediation of the effects of INTERLEUKINS and other CYTOKINES are emerging.
Antibodies produced by a single clone of cells.
Antibodies from an individual that react with ISOANTIGENS of another individual of the same species.
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
Bone marrow-derived lymphocytes that possess cytotoxic properties, classically directed against transformed and virus-infected cells. Unlike T CELLS; and B CELLS; NK CELLS are not antigen specific. The cytotoxicity of natural killer cells is determined by the collective signaling of an array of inhibitory and stimulatory CELL SURFACE RECEPTORS. A subset of T-LYMPHOCYTES referred to as NATURAL KILLER T CELLS shares some of the properties of this cell type.
One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.
Subset of helper-inducer T-lymphocytes which synthesize and secrete the interleukins IL-4, IL-5, IL-6, and IL-10. These cytokines influence B-cell development and antibody production as well as augmenting humoral responses.
Agents that cause clotting.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.
Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (Freund's adjuvant, BCG, Corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity.
Molecules on the surface of T-lymphocytes that recognize and combine with antigens. The receptors are non-covalently associated with a complex of several polypeptides collectively called CD3 antigens (ANTIGENS, CD3). Recognition of foreign antigen and the major histocompatibility complex is accomplished by a single heterodimeric antigen-receptor structure, composed of either alpha-beta (RECEPTORS, ANTIGEN, T-CELL, ALPHA-BETA) or gamma-delta (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA) chains.
The ability of organisms to sense and adapt to high concentrations of salt in their growth environment.
Proteins, glycoprotein, or lipoprotein moieties on surfaces of tumor cells that are usually identified by monoclonal antibodies. Many of these are of either embryonic or viral origin.
Biologically active substances whose activities affect or play a role in the functioning of the immune system.
An autosomal recessively inherited glycogen storage disease caused by GLUCAN 1,4-ALPHA-GLUCOSIDASE deficiency. Large amounts of GLYCOGEN accumulate in the LYSOSOMES of skeletal muscle (MUSCLE, SKELETAL); HEART; LIVER; SPINAL CORD; and BRAIN. Three forms have been described: infantile, childhood, and adult. The infantile form is fatal in infancy and presents with hypotonia and a hypertrophic cardiomyopathy (CARDIOMYOPATHY, HYPERTROPHIC). The childhood form usually presents in the second year of life with proximal weakness and respiratory symptoms. The adult form consists of a slowly progressive proximal myopathy. (From Muscle Nerve 1995;3:S61-9; Menkes, Textbook of Child Neurology, 5th ed, pp73-4)
DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.
Immunosuppression by reduction of circulating lymphocytes or by T-cell depletion of bone marrow. The former may be accomplished in vivo by thoracic duct drainage or administration of antilymphocyte serum. The latter is performed ex vivo on bone marrow before its transplantation.
Exchange of substances between the maternal blood and the fetal blood at the PLACENTA via PLACENTAL CIRCULATION. The placental barrier excludes microbial or viral transmission.
Inbred CBA mice are a strain of laboratory mice that have been selectively bred to be genetically identical and uniform, which makes them useful for scientific research, particularly in the areas of immunology and cancer.
A process in which peripheral blood is exposed in an extracorporeal flow system to photoactivated 8-methoxypsoralen (METHOXSALEN) and ultraviolet light - a procedure known as PUVA THERAPY. Photopheresis is at present a standard therapy for advanced cutaneous T-cell lymphoma; it shows promise in the treatment of autoimmune diseases.
Immunized T-lymphocytes which can directly destroy appropriate target cells. These cytotoxic lymphocytes may be generated in vitro in mixed lymphocyte cultures (MLC), in vivo during a graft-versus-host (GVH) reaction, or after immunization with an allograft, tumor cell or virally transformed or chemically modified target cell. The lytic phenomenon is sometimes referred to as cell-mediated lympholysis (CML). These CD8-positive cells are distinct from NATURAL KILLER CELLS and NATURAL KILLER T-CELLS. There are two effector phenotypes: TC1 and TC2.
Process of classifying cells of the immune system based on structural and functional differences. The process is commonly used to analyze and sort T-lymphocytes into subsets based on CD antigens by the technique of flow cytometry.
A soluble substance elaborated by antigen- or mitogen-stimulated T-LYMPHOCYTES which induces DNA synthesis in naive lymphocytes.
A specific immune response elicited by a specific dose of an immunologically active substance or cell in an organism, tissue, or cell.
55-kDa antigens found on HELPER-INDUCER T-LYMPHOCYTES and on a variety of other immune cell types. CD4 antigens are members of the immunoglobulin supergene family and are implicated as associative recognition elements in MAJOR HISTOCOMPATIBILITY COMPLEX class II-restricted immune responses. On T-lymphocytes they define the helper/inducer subset. CD4 antigens also serve as INTERLEUKIN-15 receptors and bind to the HIV receptors, binding directly to the HIV ENVELOPE PROTEIN GP120.
Enzymes that catalyze the exohydrolysis of 1,4-alpha-glucosidic linkages with release of alpha-glucose. Deficiency of alpha-1,4-glucosidase may cause GLYCOGEN STORAGE DISEASE TYPE II.
Group of diseases mediated by the deposition of large soluble complexes of antigen and antibody with resultant damage to tissue. Besides SERUM SICKNESS and the ARTHUS REACTION, evidence supports a pathogenic role for immune complexes in many other IMMUNE SYSTEM DISEASES including GLOMERULONEPHRITIS, systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC) and POLYARTERITIS NODOSA.
The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.
White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.
An experimental animal model for central nervous system demyelinating disease. Inoculation with a white matter emulsion combined with FREUND'S ADJUVANT, myelin basic protein, or purified central myelin triggers a T cell-mediated immune response directed towards central myelin. The pathologic features are similar to MULTIPLE SCLEROSIS, including perivascular and periventricular foci of inflammation and demyelination. Subpial demyelination underlying meningeal infiltrations also occurs, which is also a feature of ENCEPHALOMYELITIS, ACUTE DISSEMINATED. Passive immunization with T-cells from an afflicted animal to a normal animal also induces this condition. (From Immunol Res 1998;17(1-2):217-27; Raine CS, Textbook of Neuropathology, 2nd ed, p604-5)
Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)
Altered reactivity to an antigen, which can result in pathologic reactions upon subsequent exposure to that particular antigen.
The major group of transplantation antigens in the mouse.
Techniques and strategies which include the use of coding sequences and other conventional or radical means to transform or modify cells for the purpose of treating or reversing disease conditions.
A family of pattern recognition receptors characterized by an extracellular leucine-rich domain and a cytoplasmic domain that share homology with the INTERLEUKIN 1 RECEPTOR and the DROSOPHILA toll protein. Following pathogen recognition, toll-like receptors recruit and activate a variety of SIGNAL TRANSDUCING ADAPTOR PROTEINS.
Forceful administration into the peritoneal cavity of liquid medication, nutrient, or other fluid through a hollow needle piercing the abdominal wall.
Measure of histocompatibility at the HL-A locus. Peripheral blood lymphocytes from two individuals are mixed together in tissue culture for several days. Lymphocytes from incompatible individuals will stimulate each other to proliferate significantly (measured by tritiated thymidine uptake) whereas those from compatible individuals will not. In the one-way MLC test, the lymphocytes from one of the individuals are inactivated (usually by treatment with MITOMYCIN or radiation) thereby allowing only the untreated remaining population of cells to proliferate in response to foreign histocompatibility antigens.
Transplant comprised of an individual's own tissue, transferred from one part of the body to another.
New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.
Established cell cultures that have the potential to propagate indefinitely.
The exercise capacity of an individual as measured by endurance (maximal exercise duration and/or maximal attained work load) during an EXERCISE TEST.
A costimulatory ligand expressed by ANTIGEN-PRESENTING CELLS that binds to CTLA-4 ANTIGEN with high specificity and to CD28 ANTIGEN with low specificity. The interaction of CD80 with CD28 ANTIGEN provides a costimulatory signal to T-LYMPHOCYTES, while its interaction with CTLA-4 ANTIGEN may play a role in inducing PERIPHERAL TOLERANCE.
Administration of vaccines to stimulate the host's immune response. This includes any preparation intended for active immunological prophylaxis.
Glucose in blood.
Proteins prepared by recombinant DNA technology.
A chronic, relapsing, inflammatory, and often febrile multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidneys, and serosal membranes. It is of unknown etiology, but is thought to represent a failure of the regulatory mechanisms of the autoimmune system. The disease is marked by a wide range of system dysfunctions, an elevated erythrocyte sedimentation rate, and the formation of LE cells in the blood or bone marrow.
Antigenic determinants recognized and bound by the T-cell receptor. Epitopes recognized by the T-cell receptor are often located in the inner, unexposed side of the antigen, and become accessible to the T-cell receptors after proteolytic processing of the antigen.
Antibodies that inhibit the reaction between ANTIGEN and other antibodies or sensitized T-LYMPHOCYTES (e.g., antibodies of the IMMUNOGLOBULIN G class that compete with IGE antibodies for antigen, thereby blocking an allergic response). Blocking antibodies that bind tumors and prevent destruction of tumor cells by CYTOTOXIC T-LYMPHOCYTES have also been called enhancing antibodies. (Rosen et al., Dictionary of Immunology, 1989)
The transference of pancreatic islets within an individual, between individuals of the same species, or between individuals of different species.
Inbred DBA mice are a strain of laboratory mice that are genetically identical and share specific characteristics, including a high incidence of deafness, coat color (black and white), and susceptibility to certain diseases, which make them useful for research purposes in biomedical studies.
Prolonged dry periods in natural climate cycle. They are slow-onset phenomena caused by rainfall deficit combined with other predisposing factors.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Subpopulation of CD4+ lymphocytes that cooperate with other lymphocytes (either T or B) to initiate a variety of immune functions. For example, helper-inducer T-cells cooperate with B-cells to produce antibodies to thymus-dependent antigens and with other subpopulations of T-cells to initiate a variety of cell-mediated immune functions.
The classes of BONE MARROW-derived blood cells in the monocytic series (MONOCYTES and their precursors) and granulocytic series (GRANULOCYTES and their precursors).
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
A positive regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.
The giving of drugs, chemicals, or other substances by mouth.
A membrane glycoprotein and differentiation antigen expressed on the surface of T-cells that binds to CD40 ANTIGENS on B-LYMPHOCYTES and induces their proliferation. Mutation of the gene for CD40 ligand is a cause of HYPER-IGM IMMUNODEFICIENCY SYNDROME, TYPE 1.
'Rats, Inbred Lew' is a strain of laboratory rat that is widely used in biomedical research, known for its consistent genetic background and susceptibility to certain diseases, which makes it an ideal model for studying the genetic basis of complex traits and disease processes.
A soluble factor produced by activated T-LYMPHOCYTES that induces the expression of MHC CLASS II GENES and FC RECEPTORS on B-LYMPHOCYTES and causes their proliferation and differentiation. It also acts on T-lymphocytes, MAST CELLS, and several other hematopoietic lineage cells.
Complex of at least five membrane-bound polypeptides in mature T-lymphocytes that are non-covalently associated with one another and with the T-cell receptor (RECEPTORS, ANTIGEN, T-CELL). The CD3 complex includes the gamma, delta, epsilon, zeta, and eta chains (subunits). When antigen binds to the T-cell receptor, the CD3 complex transduces the activating signals to the cytoplasm of the T-cell. The CD3 gamma and delta chains (subunits) are separate from and not related to the gamma/delta chains of the T-cell receptor (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA).
The altered state of immunologic responsiveness resulting from initial contact with antigen, which enables the individual to produce antibodies more rapidly and in greater quantity in response to secondary antigenic stimulus.
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
The mechanism, in peripheral lymphoid organs (LYMPH NODES; SPLEEN; TONSILS; and mucosal-associated lymphoid tissue), that prevents mature lymphocytes from reacting to SELF-ANTIGENS. This is accomplished through a variety of means including CLONAL ANERGY and CLONAL DELETION.
A factor synthesized in a wide variety of tissues. It acts synergistically with TGF-alpha in inducing phenotypic transformation and can also act as a negative autocrine growth factor. TGF-beta has a potential role in embryonal development, cellular differentiation, hormone secretion, and immune function. TGF-beta is found mostly as homodimer forms of separate gene products TGF-beta1, TGF-beta2 or TGF-beta3. Heterodimers composed of TGF-beta1 and 2 (TGF-beta1.2) or of TGF-beta2 and 3 (TGF-beta2.3) have been isolated. The TGF-beta proteins are synthesized as precursor proteins.
A genus of the family PARVOVIRIDAE, subfamily PARVOVIRINAE, which are dependent on a coinfection with helper adenoviruses or herpesviruses for their efficient replication. The type species is Adeno-associated virus 2.
Antigen-type substances that produce immediate hypersensitivity (HYPERSENSITIVITY, IMMEDIATE).
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
The unfavorable effect of environmental factors (stressors) on the physiological functions of an organism. Prolonged unresolved physiological stress can affect HOMEOSTASIS of the organism, and may lead to damaging or pathological conditions.
Specialized tissues that are components of the lymphatic system. They provide fixed locations within the body where a variety of LYMPHOCYTES can form, mature and multiply. The lymphoid tissues are connected by a network of LYMPHATIC VESSELS.
The hormone-responsive glandular layer of ENDOMETRIUM that sloughs off at each menstrual flow (decidua menstrualis) or at the termination of pregnancy. During pregnancy, the thickest part of the decidua forms the maternal portion of the PLACENTA, thus named decidua placentalis. The thin portion of the decidua covering the rest of the embryo is the decidua capsularis.
Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.
Glycoproteins found on the membrane or surface of cells.
A proinflammatory cytokine produced primarily by T-LYMPHOCYTES or their precursors. Several subtypes of interleukin-17 have been identified, each of which is a product of a unique gene.
A technique of culturing mixed cell types in vitro to allow their synergistic or antagonistic interactions, such as on CELL DIFFERENTIATION or APOPTOSIS. Coculture can be of different types of cells, tissues, or organs from normal or disease states.
Cell separation is the process of isolating and distinguishing specific cell types or individual cells from a heterogeneous mixture, often through the use of physical or biological techniques.
The processes whereby the internal environment of an organism tends to remain balanced and stable.
Subset of helper-effector T-lymphocytes which synthesize and secrete IL-17, IL-17F, and IL-22. These cytokines are involved in host defenses and tissue inflammation in autoimmune diseases.
A negative regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.
Autoantibodies directed against various nuclear antigens including DNA, RNA, histones, acidic nuclear proteins, or complexes of these molecular elements. Antinuclear antibodies are found in systemic autoimmune diseases including systemic lupus erythematosus, Sjogren's syndrome, scleroderma, polymyositis, and mixed connective tissue disease.
A costimulatory ligand expressed by ANTIGEN-PRESENTING CELLS that binds to CD28 ANTIGEN with high specificity and to CTLA-4 ANTIGEN with low specificity. The interaction of CD86 with CD28 ANTIGEN provides a stimulatory signal to T-LYMPHOCYTES, while its interaction with CTLA-4 ANTIGEN may play a role in inducing PERIPHERAL TOLERANCE.
Membrane glycoproteins consisting of an alpha subunit and a BETA 2-MICROGLOBULIN beta subunit. In humans, highly polymorphic genes on CHROMOSOME 6 encode the alpha subunits of class I antigens and play an important role in determining the serological specificity of the surface antigen. Class I antigens are found on most nucleated cells and are generally detected by their reactivity with alloantisera. These antigens are recognized during GRAFT REJECTION and restrict cell-mediated lysis of virus-infected cells.
Antigens determined by leukocyte loci found on chromosome 6, the major histocompatibility loci in humans. They are polypeptides or glycoproteins found on most nucleated cells and platelets, determine tissue types for transplantation, and are associated with certain diseases.
Antigens expressed primarily on the membranes of living cells during sequential stages of maturation and differentiation. As immunologic markers they have high organ and tissue specificity and are useful as probes in studies of normal cell development as well as neoplastic transformation.
Non-human animals, selected because of specific characteristics, for use in experimental research, teaching, or testing.
A deficiency of blood coagulation factor IX inherited as an X-linked disorder. (Also known as Christmas Disease, after the first patient studied in detail, not the holy day.) Historical and clinical features resemble those in classic hemophilia (HEMOPHILIA A), but patients present with fewer symptoms. Severity of bleeding is usually similar in members of a single family. Many patients are asymptomatic until the hemostatic system is stressed by surgery or trauma. Treatment is similar to that for hemophilia A. (From Cecil Textbook of Medicine, 19th ed, p1008)
A cell line derived from cultured tumor cells.
The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.
Serum glycoprotein produced by activated MACROPHAGES and other mammalian MONONUCLEAR LEUKOCYTES. It has necrotizing activity against tumor cell lines and increases ability to reject tumor transplants. Also known as TNF-alpha, it is only 30% homologous to TNF-beta (LYMPHOTOXIN), but they share TNF RECEPTORS.
IMMUNOGLOBULINS on the surface of B-LYMPHOCYTES. Their MESSENGER RNA contains an EXON with a membrane spanning sequence, producing immunoglobulins in the form of type I transmembrane proteins as opposed to secreted immunoglobulins (ANTIBODIES) which do not contain the membrane spanning segment.
The transference of BONE MARROW from one human or animal to another for a variety of purposes including HEMATOPOIETIC STEM CELL TRANSPLANTATION or MESENCHYMAL STEM CELL TRANSPLANTATION.
The phenomenon of target cell destruction by immunologically active effector cells. It may be brought about directly by sensitized T-lymphocytes or by lymphoid or myeloid "killer" cells, or it may be mediated by cytotoxic antibody, cytotoxic factor released by lymphoid cells, or complement.
The principal alkaloid in opium and the prototype opiate analgesic and narcotic. Morphine has widespread effects in the central nervous system and on smooth muscle.
The number of LYMPHOCYTES per unit volume of BLOOD.
Antibody-mediated immune response. Humoral immunity is brought about by ANTIBODY FORMATION, resulting from TH2 CELLS activating B-LYMPHOCYTES, followed by COMPLEMENT ACTIVATION.
Cells contained in the bone marrow including fat cells (see ADIPOCYTES); STROMAL CELLS; MEGAKARYOCYTES; and the immediate precursors of most blood cells.
The section of the alimentary canal from the STOMACH to the ANAL CANAL. It includes the LARGE INTESTINE and SMALL INTESTINE.
The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).
The introduction of functional (usually cloned) GENES into cells. A variety of techniques and naturally occurring processes are used for the gene transfer such as cell hybridization, LIPOSOMES or microcell-mediated gene transfer, ELECTROPORATION, chromosome-mediated gene transfer, TRANSFECTION, and GENETIC TRANSDUCTION. Gene transfer may result in genetically transformed cells and individual organisms.
Any of several ways in which living cells of an organism communicate with one another, whether by direct contact between cells or by means of chemical signals carried by neurotransmitter substances, hormones, and cyclic AMP.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
Antigens on surfaces of cells, including infectious or foreign cells or viruses. They are usually protein-containing groups on cell membranes or walls and may be isolated.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Genes that are introduced into an organism using GENE TRANSFER TECHNIQUES.

Clusters of Pneumocystis carinii pneumonia: analysis of person-to-person transmission by genotyping. (1/6947)

Genotyping at the internal transcribed spacer (ITS) regions of the nuclear rRNA operon was performed on isolates of P. carinii sp. f. hominis from three clusters of P. carinii pneumonia among eight patients with haematological malignancies and six with HIV infection. Nine different ITS sequence types of P. carinii sp. f. hominis were identified in the samples from the patients with haematological malignancies, suggesting that this cluster of cases of P. carinii pneumonia was unlikely to have resulted from nosocomial transmission. A common ITS sequence type was observed in two of the patients with haematological malignancies who shared a hospital room, and also in two of the patients with HIV infection who had prolonged close contact on the ward. In contrast, different ITS sequence types were detected in samples from an HIV-infected homosexual couple who shared the same household. These data suggest that person-to-person transmission of P. carinii sp. f. hominis may occur from infected to susceptible immunosuppressed patients with close contact within hospital environments. However direct transmission between patients did not account for the majority of cases within the clusters, suggesting that person-to-person transmission of P. carinii sp. f. hominis infection may be a relatively infrequent event and does not constitute the major route of transmission in man.  (+info)

Development and function of autospecific dual TCR+ T lymphocytes. (2/6947)

Recent studies have challenged the long held concept that each T lymphocyte expresses on its surface only a single, unique alphabetaTCR. Dual TCR+ T cells have been recognized, however, their origin and potential to escape screening for self-reactivity remain obscure. We now report the thymic generation of dual alphabetaTCR+ T cells in the H-2Db/H-Y-specific TCR transgenic (Tg) mouse. Dual TCR+ thymocytes were positively selected less efficiently than single TCR+ thymocytes, although a subset attained maturity. Importantly, when TCR Tg mice were bred onto a negatively selecting background, auto-specific cells survived central deletion and matured as CD4+ dual TCR+ cells. These cells were autoreactive when CD8 expression was restored. The existence of autospecific, dual TCR+ T cells may have implications for the maintenance of self tolerance.  (+info)

Immunosurveillance of alglucerase enzyme therapy for Gaucher patients: induction of humoral tolerance in seroconverted patients after repeat administration. (3/6947)

Alglucerase, a macrophage-targeted enzyme replacement therapy for Gaucher disease, has been successfully used for several years to improve clinical symptoms and reverse disease progression. As part of an immunosurveillance program, 1,122 Gaucher patients were monitored for antibody response to glucocerebrosidase, the active component of alglucerase. Seroconversion was detected in 142 patients (12.8%) by enzyme-linked immunosorbent assay (ELISA) and confirmed by radioimmunoprecipitation. The majority (75%) of the seroconverted population had no detectable levels of circulating inhibitory antibody as assessed by in vitro inhibition of enzymatic activity of the therapeutic molecule. Of the remaining patients with putative inhibitory antibodies, the majority had only low levels of serum inhibitory activity, which was transient. A very small number of patients were identified as developing true neutralizing antibodies, as defined by the development of antibodies that impacted clinical efficacy. Many of the patient antibody responses were also diminished with time. Eighty-two of the 142 seroconverted patients have stopped producing antibody to the molecule and appear tolerized. The mean time for humoral tolerization was 28 months from initiation of therapy. Of 64 seroconverted patients followed for at least 30 months of therapy, the tolerization rate was 93%. These results show that although 12.8% of the patients on therapy developed antibodies to the molecule, 90% of these patients became tolerized over time.  (+info)

Tolerance to antigen-presenting cell-depleted islet allografts is CD4 T cell dependent. (4/6947)

Pretreatment of pancreatic islets in 95% oxygen culture depletes graft-associated APCs and leads to indefinite allograft acceptance in immunocompetent recipients. As such, the APC-depleted allograft represents a model of peripheral alloantigen presentation in the absence of donor-derived costimulation. Over time, a state of donor-specific tolerance develops in which recipients are resistant to donor APC-induced graft rejection. Thus, persistence of the graft is sufficient to induce tolerance independent of other immune interventions. Donor-specific tolerance could be adoptively transferred to immune-deficient SCID recipient mice transplanted with fresh immunogenic islet allografts, indicating that the original recipient was not simply "ignorant" of donor antigens. Interestingly, despite the fact that the original islet allograft presented only MHC class I alloantigens, CD8+ T cells obtained from tolerant animals readily collaborated with naive CD4+ T cells to reject donor-type islet grafts. Conversely, tolerant CD4+ T cells failed to collaborate effectively with naive CD8+ T cells for the rejection of donor-type grafts. In conclusion, the MHC class I+, II- islet allograft paradoxically leads to a change in the donor-reactive CD4 T cell subset and not in the CD8 subset. We hypothesize that the tolerant state is not due to direct class I alloantigen presentation to CD8 T cells but, rather, occurs via the indirect pathway of donor Ag presentation to CD4 T cells in the context of host MHC class II molecules.  (+info)

IL-4 and IL-10 are both required for the induction of oral tolerance. (5/6947)

Protection from the development of experimental autoimmune uveitis (EAU) can be induced by feeding mice interphotoreceptor retinoid binding protein before uveitogenic challenge with the same protein. Two different regimens are equally effective in inducing protective tolerance, although they seem to do so through different mechanisms: one involving regulatory cytokines (IL-4, IL-10, and TGF-beta), and the other with minimal involvement of cytokines. Here we studied the importance of IL-4 and IL-10 for the development of oral tolerance using mice genetically engineered to lack either one or both of these cytokines. In these animals we were able to protect against EAU only through the regimen inducing cytokine-independent tolerance. When these animals were fed a regimen that in the wild-type animal is thought to predominantly induce regulatory cells and is associated with cytokine secretion, they were not protected from EAU. Interestingly, both regimens were associated with reduced IL-2 production and proliferation in response to interphotoreceptor retinoid binding protein. These findings indicate that both IL-4 and IL-10 are required for induction of protective oral tolerance dependent on regulatory cytokines, and that one cytokine cannot substitute for the other in this process. These data also underscore the fact that oral tolerance, manifested as suppression of proliferation and IL-2 production, is not synonymous with protection from disease.  (+info)

Altered helper T lymphocyte function associated with chronic hepatitis B virus infection and its role in response to therapeutic vaccination in humans. (6/6947)

Theradigm-hepatitis B virus (HBV) is an experimental lipopeptide vaccine designed to stimulate induction of HBV-specific CTL responses in HLA-A2 individuals. Previous studies had demonstrated high immunogenicity in healthy volunteers, but comparatively weak CTL responses in chronically infected HBV patients. Herein, we examined helper T lymphocyte (HTL) responses in chronically infected patients. Despite normal proliferation and IL-2 secretion, IL-12 and IFN-gamma secretion in vitro in response to the vaccine was reduced compared with healthy volunteers. A similar pattern of cytokine secretion was observed following mitogen stimulation, suggesting a general altered balance of Th1/Th2 responses. Further analysis indicated that HTL recall responses to whole tetanus toxoid protein were reduced in chronically infected subjects, and reduced responsiveness correlated with the outcome of Theradigm-HBV immunization. Finally, experiments in HBV transgenic mice indicated that the nonnatural Pan DR HTL epitope, PADRE, is capable of inducing high levels of IFN-gamma secretion and that its inclusion in a lipopeptide incorporating an immunodominant Ld-restricted CTL epitope resulted in breaking tolerance at the CTL level. Overall, our results demonstrate an alteration in the quality of HTL responses induced in chronically infected HBV patients and suggest that use of a potent HTL epitope may be important to overcome CTL tolerance against specific HBV Ags.  (+info)

Activation in vivo of retroperitoneal fibromatosis-associated herpesvirus, a simian homologue of human herpesvirus-8. (7/6947)

Retroperitoneal fibromatosis-associated herpesvirus of rhesus macaques (RFHVMm) is a gammaherpesvirus closely related to human herpesvirus-8 (HHV-8), which is thought to be a necessary cofactor for the development of Kaposi's sarcoma (KS) in humans. Here, RFHVMm infection of rhesus macaques exposed to the D-type retrovirus simian retrovirus-2 (SRV-2) is described. Development of SRV-2 viraemia, infection with simian immunodeficiency virus or administration of cyclosporin A could result in persistent RFHVMm viraemia. From this, it is concluded that productive retrovirus infection or otherwise-induced immune suppression has the ability to activate this herpesvirus in vivo. Elevated levels of circulating interleukin-6, a cytokine that plays a central role in KS, were found in RFHVMm-viraemic animals. In viraemic animals, RFHVMm was found in tissues that are common sites for the development of AIDS-associated KS, especially the oral cavity. Together, these data suggest a common biology between RFHVMm infection of macaques and HHV-8 infection and pathogenesis in humans.  (+info)

B7-2 expressed on EL4 lymphoma suppresses antitumor immunity by an interleukin 4-dependent mechanism. (8/6947)

For T cells to become functionally activated they require at least two signals. The B7 costimulatory molecules B7-1 and B7-2 provide the "second signal" pivotal for T cell activation. In this report, we studied the relative roles of B7-1 and B7-2 molecules in the induction of antitumor immunity to the T cell thymoma, EL4. We generated EL4 tumor cells that expressed B7-1, B7-2, and B7-1+B7-2 by transfecting murine cDNAs. Our results demonstrate that EL4-B7-1 cells are completely rejected in syngeneic mice. Unlike EL4-B7-1 cells, we find that EL4-B7-2 cells are not rejected but progressively grow in the mice. A B7-1- and B7-2-EL4 double transfectant was generated by introducing B7-2 cDNA into the EL4-B7-1 tumor line that regressed in vivo. The EL4-B7-1+B7-2 double transfectant was not rejected when implanted into syngeneic mice but progressively grew to produce tumors. The double transfectant EL4 cells could costimulate T cell proliferation that could be blocked by anti-B7-1 antibodies, anti-B7-2 antibodies, or hCTLA4 immunoglobulin, showing that the B7-1 and B7-2 molecules expressed on the EL4 cells were functional. In vivo, treatment of mice implanted with double-transfected EL4 cells with anti-B7-2 monoclonal antibody resulted in tumor rejection. Furthermore, the EL4-B7-2 and EL4-B7-1+B7-2 cells, but not the wild-type EL4 cells, were rejected in interleukin 4 (IL-4) knockout mice. Our data suggests that B7-2 expressed on some T cell tumors inhibits development of antitumor immunity, and IL-4 appears to play a critical role in abrogation of the antitumor immune response.  (+info)

Immune tolerance, also known as immunological tolerance or specific immune tolerance, is a state of unresponsiveness or non-reactivity of the immune system towards a particular substance (antigen) that has the potential to elicit an immune response. This occurs when the immune system learns to distinguish "self" from "non-self" and does not attack the body's own cells, tissues, and organs.

In the context of transplantation, immune tolerance refers to the absence of a destructive immune response towards the transplanted organ or tissue, allowing for long-term graft survival without the need for immunosuppressive therapy. Immune tolerance can be achieved through various strategies, including hematopoietic stem cell transplantation, costimulation blockade, and regulatory T cell induction.

In summary, immune tolerance is a critical mechanism that prevents the immune system from attacking the body's own structures while maintaining the ability to respond appropriately to foreign pathogens and antigens.

Drug tolerance is a medical concept that refers to the decreased response to a drug following its repeated use, requiring higher doses to achieve the same effect. This occurs because the body adapts to the presence of the drug, leading to changes in the function or expression of targets that the drug acts upon, such as receptors or enzymes. Tolerance can develop to various types of drugs, including opioids, benzodiazepines, and alcohol, and it is often associated with physical dependence and addiction. It's important to note that tolerance is different from resistance, which refers to the ability of a pathogen to survive or grow in the presence of a drug, such as antibiotics.

The immune system is a complex network of cells, tissues, and organs that work together to defend the body against harmful invaders. It recognizes and responds to threats such as bacteria, viruses, parasites, fungi, and damaged or abnormal cells, including cancer cells. The immune system has two main components: the innate immune system, which provides a general defense against all types of threats, and the adaptive immune system, which mounts specific responses to particular threats.

The innate immune system includes physical barriers like the skin and mucous membranes, chemical barriers such as stomach acid and enzymes in tears and saliva, and cellular defenses like phagocytes (white blood cells that engulf and destroy invaders) and natural killer cells (which recognize and destroy virus-infected or cancerous cells).

The adaptive immune system is more specific and takes longer to develop a response but has the advantage of "remembering" previous encounters with specific threats. This allows it to mount a faster and stronger response upon subsequent exposures, providing immunity to certain diseases. The adaptive immune system includes T cells (which help coordinate the immune response) and B cells (which produce antibodies that neutralize or destroy invaders).

Overall, the immune system is essential for maintaining health and preventing disease. Dysfunction of the immune system can lead to a variety of disorders, including autoimmune diseases, immunodeficiencies, and allergies.

Transplantation tolerance, also known as immunological tolerance or transplant tolerance, is a state in which the immune system of a transplant recipient does not mount an immune response against the transplanted organ or tissue. This is an important goal in transplantation medicine to prevent graft rejection and reduce the need for long-term immunosuppressive therapy, which can have significant side effects.

Transplantation tolerance can be achieved through various mechanisms, including the deletion or regulation of donor-reactive T cells, the induction of regulatory T cells (Tregs) that suppress immune responses against the graft, and the modulation of innate immune responses. The development of strategies to induce transplantation tolerance is an active area of research in transplantation medicine.

Regulatory T-lymphocytes (Tregs), also known as suppressor T cells, are a subpopulation of T-cells that play a critical role in maintaining immune tolerance and preventing autoimmune diseases. They function to suppress the activation and proliferation of other immune cells, thereby regulating the immune response and preventing it from attacking the body's own tissues.

Tregs constitutively express the surface markers CD4 and CD25, as well as the transcription factor Foxp3, which is essential for their development and function. They can be further divided into subsets based on their expression of other markers, such as CD127 and CD45RA.

Tregs are critical for maintaining self-tolerance by suppressing the activation of self-reactive T cells that have escaped negative selection in the thymus. They also play a role in regulating immune responses to foreign antigens, such as those encountered during infection or cancer, and can contribute to the immunosuppressive microenvironment found in tumors.

Dysregulation of Tregs has been implicated in various autoimmune diseases, including type 1 diabetes, rheumatoid arthritis, and multiple sclerosis, as well as in cancer and infectious diseases. Therefore, understanding the mechanisms that regulate Treg function is an important area of research with potential therapeutic implications.

Self tolerance, also known as immunological tolerance or biological tolerance, is a critical concept in the field of immunology. It refers to the ability of the immune system to distinguish between "self" and "non-self" antigens and to refrain from mounting an immune response against its own cells, tissues, and organs.

In other words, self tolerance is the state of immune non-responsiveness to self antigens, which are molecules or structures that are normally present in an individual's own body. This ensures that the immune system does not attack the body's own cells and cause autoimmune diseases.

Self tolerance is established during the development and maturation of the immune system, particularly in the thymus gland for T cells and the bone marrow for B cells. During this process, immature immune cells that recognize self antigens are either eliminated or rendered tolerant to them, so that they do not mount an immune response against the body's own tissues.

Maintaining self tolerance is essential for the proper functioning of the immune system and for preventing the development of autoimmune diseases, in which the immune system mistakenly attacks the body's own cells and tissues.

C57BL/6 (C57 Black 6) is an inbred strain of laboratory mouse that is widely used in biomedical research. The term "inbred" refers to a strain of animals where matings have been carried out between siblings or other closely related individuals for many generations, resulting in a population that is highly homozygous at most genetic loci.

The C57BL/6 strain was established in 1920 by crossing a female mouse from the dilute brown (DBA) strain with a male mouse from the black strain. The resulting offspring were then interbred for many generations to create the inbred C57BL/6 strain.

C57BL/6 mice are known for their robust health, longevity, and ease of handling, making them a popular choice for researchers. They have been used in a wide range of biomedical research areas, including studies of cancer, immunology, neuroscience, cardiovascular disease, and metabolism.

One of the most notable features of the C57BL/6 strain is its sensitivity to certain genetic modifications, such as the introduction of mutations that lead to obesity or impaired glucose tolerance. This has made it a valuable tool for studying the genetic basis of complex diseases and traits.

Overall, the C57BL/6 inbred mouse strain is an important model organism in biomedical research, providing a valuable resource for understanding the genetic and molecular mechanisms underlying human health and disease.

A Glucose Tolerance Test (GTT) is a medical test used to diagnose prediabetes, type 2 diabetes, and gestational diabetes. It measures how well your body is able to process glucose, which is a type of sugar.

During the test, you will be asked to fast (not eat or drink anything except water) for at least eight hours before the test. Then, a healthcare professional will take a blood sample to measure your fasting blood sugar level. After that, you will be given a sugary drink containing a specific amount of glucose. Your blood sugar levels will be measured again after two hours and sometimes also after one hour.

The results of the test will indicate how well your body is able to process the glucose and whether you have normal, impaired, or diabetic glucose tolerance. If your blood sugar levels are higher than normal but not high enough to be diagnosed with diabetes, you may have prediabetes, which means that you are at increased risk of developing type 2 diabetes in the future.

It is important to note that a Glucose Tolerance Test should be performed under the supervision of a healthcare professional, as high blood sugar levels can be dangerous if not properly managed.

T-lymphocytes, also known as T-cells, are a type of white blood cell that plays a key role in the adaptive immune system's response to infection. They are produced in the bone marrow and mature in the thymus gland. There are several different types of T-cells, including CD4+ helper T-cells, CD8+ cytotoxic T-cells, and regulatory T-cells (Tregs).

CD4+ helper T-cells assist in activating other immune cells, such as B-lymphocytes and macrophages. They also produce cytokines, which are signaling molecules that help coordinate the immune response. CD8+ cytotoxic T-cells directly kill infected cells by releasing toxic substances. Regulatory T-cells help maintain immune tolerance and prevent autoimmune diseases by suppressing the activity of other immune cells.

T-lymphocytes are important in the immune response to viral infections, cancer, and other diseases. Dysfunction or depletion of T-cells can lead to immunodeficiency and increased susceptibility to infections. On the other hand, an overactive T-cell response can contribute to autoimmune diseases and chronic inflammation.

Autoimmunity is a medical condition in which the body's immune system mistakenly attacks and destroys healthy tissues within the body. In normal function, the immune system recognizes and fights off foreign substances such as bacteria, viruses, and toxins. However, when autoimmunity occurs, the immune system identifies self-molecules or tissues as foreign and produces an immune response against them.

This misguided response can lead to chronic inflammation, tissue damage, and impaired organ function. Autoimmune diseases can affect various parts of the body, including the joints, skin, glands, muscles, and blood vessels. Some common examples of autoimmune diseases are rheumatoid arthritis, lupus, multiple sclerosis, type 1 diabetes, Hashimoto's thyroiditis, and Graves' disease.

The exact cause of autoimmunity is not fully understood, but it is believed to involve a combination of genetic, environmental, and lifestyle factors that trigger an abnormal immune response in susceptible individuals. Treatment for autoimmune diseases typically involves managing symptoms, reducing inflammation, and suppressing the immune system's overactive response using medications such as corticosteroids, immunosuppressants, and biologics.

Dendritic cells (DCs) are a type of immune cell that play a critical role in the body's defense against infection and cancer. They are named for their dendrite-like projections, which they use to interact with and sample their environment. DCs are responsible for processing antigens (foreign substances that trigger an immune response) and presenting them to T cells, a type of white blood cell that plays a central role in the immune system's response to infection and cancer.

DCs can be found throughout the body, including in the skin, mucous membranes, and lymphoid organs. They are able to recognize and respond to a wide variety of antigens, including those from bacteria, viruses, fungi, and parasites. Once they have processed an antigen, DCs migrate to the lymph nodes, where they present the antigen to T cells. This interaction activates the T cells, which then go on to mount a targeted immune response against the invading pathogen or cancerous cells.

DCs are a diverse group of cells that can be divided into several subsets based on their surface markers and function. Some DCs, such as Langerhans cells and dermal DCs, are found in the skin and mucous membranes, where they serve as sentinels for invading pathogens. Other DCs, such as plasmacytoid DCs and conventional DCs, are found in the lymphoid organs, where they play a role in activating T cells and initiating an immune response.

Overall, dendritic cells are essential for the proper functioning of the immune system, and dysregulation of these cells has been implicated in a variety of diseases, including autoimmune disorders and cancer.

Hemophilia A is a genetic bleeding disorder caused by a deficiency in clotting factor VIII. This results in impaired blood clotting and prolonged bleeding, particularly after injuries or surgeries. Symptoms can range from mild to severe, with the most severe form resulting in spontaneous bleeding into joints and muscles, leading to pain, swelling, and potential joint damage over time. Hemophilia A primarily affects males, as it is an X-linked recessive disorder, and is usually inherited from a carrier mother. However, about one third of cases result from a spontaneous mutation in the gene for factor VIII. Treatment typically involves replacement therapy with infusions of factor VIII concentrates to prevent or control bleeding episodes.

BALB/c is an inbred strain of laboratory mouse that is widely used in biomedical research. The strain was developed at the Institute of Cancer Research in London by Henry Baldwin and his colleagues in the 1920s, and it has since become one of the most commonly used inbred strains in the world.

BALB/c mice are characterized by their black coat color, which is determined by a recessive allele at the tyrosinase locus. They are also known for their docile and friendly temperament, making them easy to handle and work with in the laboratory.

One of the key features of BALB/c mice that makes them useful for research is their susceptibility to certain types of tumors and immune responses. For example, they are highly susceptible to developing mammary tumors, which can be induced by chemical carcinogens or viral infection. They also have a strong Th2-biased immune response, which makes them useful models for studying allergic diseases and asthma.

BALB/c mice are also commonly used in studies of genetics, neuroscience, behavior, and infectious diseases. Because they are an inbred strain, they have a uniform genetic background, which makes it easier to control for genetic factors in experiments. Additionally, because they have been bred in the laboratory for many generations, they are highly standardized and reproducible, making them ideal subjects for scientific research.

Lymphocyte activation is the process by which B-cells and T-cells (types of lymphocytes) become activated to perform effector functions in an immune response. This process involves the recognition of specific antigens presented on the surface of antigen-presenting cells, such as dendritic cells or macrophages.

The activation of B-cells leads to their differentiation into plasma cells that produce antibodies, while the activation of T-cells results in the production of cytotoxic T-cells (CD8+ T-cells) that can directly kill infected cells or helper T-cells (CD4+ T-cells) that assist other immune cells.

Lymphocyte activation involves a series of intracellular signaling events, including the binding of co-stimulatory molecules and the release of cytokines, which ultimately result in the expression of genes involved in cell proliferation, differentiation, and effector functions. The activation process is tightly regulated to prevent excessive or inappropriate immune responses that can lead to autoimmunity or chronic inflammation.

Indoleamine-2,3-dioxygenase (IDO) is an enzyme that catalyzes the oxidation of L-tryptophan to N-formylkynurenine, which is the first and rate-limiting step in the kynurenine pathway. This enzymatic reaction plays a crucial role in regulating tryptophan metabolism and immune responses. IDO is expressed in various tissues, including the brain, liver, and placenta, as well as in some immune cells such as dendritic cells and macrophages. It can be upregulated by inflammatory stimuli, and its expression has been associated with immune tolerance and suppression of T-cell responses. IDO is also being investigated as a potential therapeutic target for various diseases, including cancer, autoimmune disorders, and neuropsychiatric conditions.

Forkhead transcription factors (FOX) are a family of proteins that play crucial roles in the regulation of gene expression through the process of binding to specific DNA sequences, thereby controlling various biological processes such as cell growth, differentiation, and apoptosis. These proteins are characterized by a conserved DNA-binding domain, known as the forkhead box or FOX domain, which adopts a winged helix structure that recognizes and binds to the consensus sequence 5'-(G/A)(T/C)AA(C/A)A-3'.

The FOX family is further divided into subfamilies based on the structure of their DNA-binding domains, with each subfamily having distinct functions. For example, FOXP proteins are involved in brain development and function, while FOXO proteins play a key role in regulating cellular responses to stress and metabolism. Dysregulation of forkhead transcription factors has been implicated in various diseases, including cancer, diabetes, and neurodegenerative disorders.

Autoantigens are substances that are typically found in an individual's own body, but can stimulate an immune response because they are recognized as foreign by the body's own immune system. In autoimmune diseases, the immune system mistakenly attacks and damages healthy tissues and organs because it recognizes some of their components as autoantigens. These autoantigens can be proteins, DNA, or other molecules that are normally present in the body but have become altered or exposed due to various factors such as infection, genetics, or environmental triggers. The immune system then produces antibodies and activates immune cells to attack these autoantigens, leading to tissue damage and inflammation.

Transgenic mice are genetically modified rodents that have incorporated foreign DNA (exogenous DNA) into their own genome. This is typically done through the use of recombinant DNA technology, where a specific gene or genetic sequence of interest is isolated and then introduced into the mouse embryo. The resulting transgenic mice can then express the protein encoded by the foreign gene, allowing researchers to study its function in a living organism.

The process of creating transgenic mice usually involves microinjecting the exogenous DNA into the pronucleus of a fertilized egg, which is then implanted into a surrogate mother. The offspring that result from this procedure are screened for the presence of the foreign DNA, and those that carry the desired genetic modification are used to establish a transgenic mouse line.

Transgenic mice have been widely used in biomedical research to model human diseases, study gene function, and test new therapies. They provide a valuable tool for understanding complex biological processes and developing new treatments for a variety of medical conditions.

Autoimmune diseases are a group of disorders in which the immune system, which normally protects the body from foreign invaders like bacteria and viruses, mistakenly attacks the body's own cells and tissues. This results in inflammation and damage to various organs and tissues in the body.

In autoimmune diseases, the body produces autoantibodies that target its own proteins or cell receptors, leading to their destruction or malfunction. The exact cause of autoimmune diseases is not fully understood, but it is believed that a combination of genetic and environmental factors contribute to their development.

There are over 80 different types of autoimmune diseases, including rheumatoid arthritis, lupus, multiple sclerosis, type 1 diabetes, Hashimoto's thyroiditis, Graves' disease, psoriasis, and inflammatory bowel disease. Symptoms can vary widely depending on the specific autoimmune disease and the organs or tissues affected. Treatment typically involves managing symptoms and suppressing the immune system to prevent further damage.

CD4-positive T-lymphocytes, also known as CD4+ T cells or helper T cells, are a type of white blood cell that plays a crucial role in the immune response. They express the CD4 receptor on their surface and help coordinate the immune system's response to infectious agents such as viruses and bacteria.

CD4+ T cells recognize and bind to specific antigens presented by antigen-presenting cells, such as dendritic cells or macrophages. Once activated, they can differentiate into various subsets of effector cells, including Th1, Th2, Th17, and Treg cells, each with distinct functions in the immune response.

CD4+ T cells are particularly important in the immune response to HIV (human immunodeficiency virus), which targets and destroys these cells, leading to a weakened immune system and increased susceptibility to opportunistic infections. The number of CD4+ T cells is often used as a marker of disease progression in HIV infection, with lower counts indicating more advanced disease.

Cytokines are a broad and diverse category of small signaling proteins that are secreted by various cells, including immune cells, in response to different stimuli. They play crucial roles in regulating the immune response, inflammation, hematopoiesis, and cellular communication.

Cytokines mediate their effects by binding to specific receptors on the surface of target cells, which triggers intracellular signaling pathways that ultimately result in changes in gene expression, cell behavior, and function. Some key functions of cytokines include:

1. Regulating the activation, differentiation, and proliferation of immune cells such as T cells, B cells, natural killer (NK) cells, and macrophages.
2. Coordinating the inflammatory response by recruiting immune cells to sites of infection or tissue damage and modulating their effector functions.
3. Regulating hematopoiesis, the process of blood cell formation in the bone marrow, by controlling the proliferation, differentiation, and survival of hematopoietic stem and progenitor cells.
4. Modulating the development and function of the nervous system, including neuroinflammation, neuroprotection, and neuroregeneration.

Cytokines can be classified into several categories based on their structure, function, or cellular origin. Some common types of cytokines include interleukins (ILs), interferons (IFNs), tumor necrosis factors (TNFs), chemokines, colony-stimulating factors (CSFs), and transforming growth factors (TGFs). Dysregulation of cytokine production and signaling has been implicated in various pathological conditions, such as autoimmune diseases, chronic inflammation, cancer, and neurodegenerative disorders.

Innate immunity, also known as non-specific immunity or natural immunity, is the inherent defense mechanism that provides immediate protection against potentially harmful pathogens (like bacteria, viruses, fungi, and parasites) without the need for prior exposure. This type of immunity is present from birth and does not adapt to specific threats over time.

Innate immune responses involve various mechanisms such as:

1. Physical barriers: Skin and mucous membranes prevent pathogens from entering the body.
2. Chemical barriers: Enzymes, stomach acid, and lysozyme in tears, saliva, and sweat help to destroy or inhibit the growth of microorganisms.
3. Cellular responses: Phagocytic cells (neutrophils, monocytes, macrophages) recognize and engulf foreign particles and pathogens, while natural killer (NK) cells target and eliminate virus-infected or cancerous cells.
4. Inflammatory response: When an infection occurs, the innate immune system triggers inflammation to increase blood flow, recruit immune cells, and remove damaged tissue.
5. Complement system: A group of proteins that work together to recognize and destroy pathogens directly or enhance phagocytosis by coating them with complement components (opsonization).

Innate immunity plays a crucial role in initiating the adaptive immune response, which is specific to particular pathogens and provides long-term protection through memory cells. Both innate and adaptive immunity work together to maintain overall immune homeostasis and protect the body from infections and diseases.

The Interleukin-2 Receptor alpha Subunit (IL-2Rα), also known as CD25, is a protein that is expressed on the surface of certain immune cells, such as activated T-cells and B-cells. It is a subunit of the interleukin-2 receptor, which plays a crucial role in the activation and regulation of the immune response. The IL-2Rα binds to interleukin-2 (IL-2) with high affinity, forming a complex that initiates intracellular signaling pathways involved in T-cell proliferation, differentiation, and survival. IL-2Rα is also a target for immunosuppressive therapies used to prevent rejection of transplanted organs and to treat autoimmune diseases.

Factor VIII is a protein in the blood that is essential for normal blood clotting. It is also known as antihemophilic factor (AHF). Deficiency or dysfunction of this protein results in hemophilia A, a genetic disorder characterized by prolonged bleeding and easy bruising. Factor VIII works together with other proteins to help form a clot and stop bleeding at the site of an injury. It acts as a cofactor for another clotting factor, IX, in the so-called intrinsic pathway of blood coagulation. Intravenous infusions of Factor VIII concentrate are used to treat and prevent bleeding episodes in people with hemophilia A.

The spleen is an organ in the upper left side of the abdomen, next to the stomach and behind the ribs. It plays multiple supporting roles in the body:

1. It fights infection by acting as a filter for the blood. Old red blood cells are recycled in the spleen, and platelets and white blood cells are stored there.
2. The spleen also helps to control the amount of blood in the body by removing excess red blood cells and storing platelets.
3. It has an important role in immune function, producing antibodies and removing microorganisms and damaged red blood cells from the bloodstream.

The spleen can be removed without causing any significant problems, as other organs take over its functions. This is known as a splenectomy and may be necessary if the spleen is damaged or diseased.

Immunotherapy is a type of medical treatment that uses the body's own immune system to fight against diseases, such as cancer. It involves the use of substances (like vaccines, medications, or immune cells) that stimulate or suppress the immune system to help it recognize and destroy harmful disease-causing cells or agents, like tumor cells.

Immunotherapy can work in several ways:

1. Activating the immune system: Certain immunotherapies boost the body's natural immune responses, helping them recognize and attack cancer cells more effectively.
2. Suppressing immune system inhibitors: Some immunotherapies target and block proteins or molecules that can suppress the immune response, allowing the immune system to work more efficiently against diseases.
3. Replacing or enhancing specific immune cells: Immunotherapy can also involve administering immune cells (like T-cells) that have been genetically engineered or modified to recognize and destroy cancer cells.

Immunotherapies have shown promising results in treating various types of cancer, autoimmune diseases, and allergies. However, they can also cause side effects, as an overactive immune system may attack healthy tissues and organs. Therefore, careful monitoring is necessary during immunotherapy treatment.

Immunosuppression is a state in which the immune system's ability to mount an immune response is reduced, compromised or inhibited. This can be caused by certain medications (such as those used to prevent rejection of transplanted organs), diseases (like HIV/AIDS), or genetic disorders. As a result, the body becomes more susceptible to infections and cancer development. It's important to note that immunosuppression should not be confused with immunity, which refers to the body's ability to resist and fight off infections and diseases.

Adoptive transfer is a medical procedure in which immune cells are transferred from a donor to a recipient with the aim of providing immunity or treating a disease, such as cancer. This technique is often used in the field of immunotherapy and involves isolating specific immune cells (like T-cells) from the donor, expanding their numbers in the laboratory, and then infusing them into the patient. The transferred cells are expected to recognize and attack the target cells, such as malignant or infected cells, leading to a therapeutic effect. This process requires careful matching of donor and recipient to minimize the risk of rejection and graft-versus-host disease.

Cellular immunity, also known as cell-mediated immunity, is a type of immune response that involves the activation of immune cells, such as T lymphocytes (T cells), to protect the body against infected or damaged cells. This form of immunity is important for fighting off infections caused by viruses and intracellular bacteria, as well as for recognizing and destroying cancer cells.

Cellular immunity involves a complex series of interactions between various immune cells and molecules. When a pathogen infects a cell, the infected cell displays pieces of the pathogen on its surface in a process called antigen presentation. This attracts T cells, which recognize the antigens and become activated. Activated T cells then release cytokines, chemicals that help coordinate the immune response, and can directly attack and kill infected cells or help activate other immune cells to do so.

Cellular immunity is an important component of the adaptive immune system, which is able to learn and remember specific pathogens in order to mount a faster and more effective response upon subsequent exposure. This form of immunity is also critical for the rejection of transplanted organs, as the immune system recognizes the transplanted tissue as foreign and attacks it.

A "knockout" mouse is a genetically engineered mouse in which one or more genes have been deleted or "knocked out" using molecular biology techniques. This allows researchers to study the function of specific genes and their role in various biological processes, as well as potential associations with human diseases. The mice are generated by introducing targeted DNA modifications into embryonic stem cells, which are then used to create a live animal. Knockout mice have been widely used in biomedical research to investigate gene function, disease mechanisms, and potential therapeutic targets.

Immune system diseases, also known as immunological disorders or autoimmune diseases, refer to a group of conditions in which the immune system mistakenly attacks and damages healthy tissues in the body. The immune system is designed to protect the body from harmful substances such as viruses, bacteria, and toxins. However, in immune system diseases, the immune system fails to distinguish between these harmful substances and the body's own cells, leading to an overactive or misdirected response.

There are several types of immune system diseases, including:

1. Allergies: An abnormal immune response to harmless substances such as pollen, dust mites, or certain foods.
2. Autoimmune disorders: A group of conditions in which the immune system attacks healthy tissues, such as rheumatoid arthritis, lupus, and multiple sclerosis.
3. Immunodeficiency disorders: Conditions that weaken the immune system, making it harder for the body to fight off infections, such as HIV/AIDS or primary immunodeficiency diseases.
4. Autoinflammatory disorders: A group of conditions characterized by recurrent episodes of inflammation due to abnormal activation of the immune system, such as familial Mediterranean fever and cryopyrin-associated periodic syndromes.
5. Transplant rejection: A response in which the immune system attacks and rejects transplanted organs or tissues.

Immune system diseases can cause a wide range of symptoms, depending on the specific condition and the severity of the disease. Treatment may involve medications to suppress the immune system, as well as other therapies to manage symptoms and prevent complications.

Interleukin-10 (IL-10) is an anti-inflammatory cytokine that plays a crucial role in the modulation of immune responses. It is produced by various cell types, including T cells, macrophages, and dendritic cells. IL-10 inhibits the production of pro-inflammatory cytokines, such as TNF-α, IL-1, IL-6, IL-8, and IL-12, and downregulates the expression of costimulatory molecules on antigen-presenting cells. This results in the suppression of T cell activation and effector functions, which ultimately helps to limit tissue damage during inflammation and promote tissue repair. Dysregulation of IL-10 has been implicated in various pathological conditions, including chronic infections, autoimmune diseases, and cancer.

B-lymphocytes, also known as B-cells, are a type of white blood cell that plays a key role in the immune system's response to infection. They are responsible for producing antibodies, which are proteins that help to neutralize or destroy pathogens such as bacteria and viruses.

When a B-lymphocyte encounters a pathogen, it becomes activated and begins to divide and differentiate into plasma cells, which produce and secrete large amounts of antibodies specific to the antigens on the surface of the pathogen. These antibodies bind to the pathogen, marking it for destruction by other immune cells such as neutrophils and macrophages.

B-lymphocytes also have a role in presenting antigens to T-lymphocytes, another type of white blood cell involved in the immune response. This helps to stimulate the activation and proliferation of T-lymphocytes, which can then go on to destroy infected cells or help to coordinate the overall immune response.

Overall, B-lymphocytes are an essential part of the adaptive immune system, providing long-lasting immunity to previously encountered pathogens and helping to protect against future infections.

Cancer vaccines are a type of immunotherapy that stimulate the body's own immune system to recognize and destroy cancer cells. They can be prophylactic (preventive) or therapeutic (treatment) in nature. Prophylactic cancer vaccines, such as the human papillomavirus (HPV) vaccine, are designed to prevent the initial infection that can lead to certain types of cancer. Therapeutic cancer vaccines, on the other hand, are used to treat existing cancer by boosting the immune system's ability to identify and eliminate cancer cells. These vaccines typically contain specific antigens (proteins or sugars) found on the surface of cancer cells, which help the immune system to recognize and target them.

It is important to note that cancer vaccines are different from vaccines used to prevent infectious diseases, such as measles or influenza. While traditional vaccines introduce a weakened or inactivated form of a virus or bacteria to stimulate an immune response, cancer vaccines focus on training the immune system to recognize and attack cancer cells specifically.

There are several types of cancer vaccines under investigation, including:

1. Autologous cancer vaccines: These vaccines use the patient's own tumor cells, which are processed and then reintroduced into the body to stimulate an immune response.
2. Peptide-based cancer vaccines: These vaccines contain specific pieces (peptides) of proteins found on the surface of cancer cells. They are designed to trigger an immune response against cells that express these proteins.
3. Dendritic cell-based cancer vaccines: Dendritic cells are a type of immune cell responsible for presenting antigens to other immune cells, activating them to recognize and destroy infected or cancerous cells. In this approach, dendritic cells are isolated from the patient's blood, exposed to cancer antigens in the lab, and then reintroduced into the body to stimulate an immune response.
4. DNA-based cancer vaccines: These vaccines use pieces of DNA that code for specific cancer antigens. Once inside the body, these DNA fragments are taken up by cells, leading to the production of the corresponding antigen and triggering an immune response.
5. Viral vector-based cancer vaccines: In this approach, a harmless virus is modified to carry genetic material encoding cancer antigens. When introduced into the body, the virus infects cells, causing them to produce the cancer antigen and stimulating an immune response.

While some cancer vaccines have shown promising results in clinical trials, none have yet been approved for widespread use by regulatory authorities such as the US Food and Drug Administration (FDA). Researchers continue to explore and refine various vaccine strategies to improve their efficacy and safety.

Flow cytometry is a medical and research technique used to measure physical and chemical characteristics of cells or particles, one cell at a time, as they flow in a fluid stream through a beam of light. The properties measured include:

* Cell size (light scatter)
* Cell internal complexity (granularity, also light scatter)
* Presence or absence of specific proteins or other molecules on the cell surface or inside the cell (using fluorescent antibodies or other fluorescent probes)

The technique is widely used in cell counting, cell sorting, protein engineering, biomarker discovery and monitoring disease progression, particularly in hematology, immunology, and cancer research.

An antigen is a substance (usually a protein) that is recognized as foreign by the immune system and stimulates an immune response, leading to the production of antibodies or activation of T-cells. Antigens can be derived from various sources, including bacteria, viruses, fungi, parasites, and tumor cells. They can also come from non-living substances such as pollen, dust mites, or chemicals.

Antigens contain epitopes, which are specific regions on the antigen molecule that are recognized by the immune system. The immune system's response to an antigen depends on several factors, including the type of antigen, its size, and its location in the body.

In general, antigens can be classified into two main categories:

1. T-dependent antigens: These require the help of T-cells to stimulate an immune response. They are typically larger, more complex molecules that contain multiple epitopes capable of binding to both MHC class II molecules on antigen-presenting cells and T-cell receptors on CD4+ T-cells.
2. T-independent antigens: These do not require the help of T-cells to stimulate an immune response. They are usually smaller, simpler molecules that contain repetitive epitopes capable of cross-linking B-cell receptors and activating them directly.

Understanding antigens and their properties is crucial for developing vaccines, diagnostic tests, and immunotherapies.

Antibody formation, also known as humoral immune response, is the process by which the immune system produces proteins called antibodies in response to the presence of a foreign substance (antigen) in the body. This process involves several steps:

1. Recognition: The antigen is recognized and bound by a type of white blood cell called a B lymphocyte or B cell, which then becomes activated.
2. Differentiation: The activated B cell undergoes differentiation to become a plasma cell, which is a type of cell that produces and secretes large amounts of antibodies.
3. Antibody production: The plasma cells produce and release antibodies, which are proteins made up of four polypeptide chains (two heavy chains and two light chains) arranged in a Y-shape. Each antibody has two binding sites that can recognize and bind to specific regions on the antigen called epitopes.
4. Neutralization or elimination: The antibodies bind to the antigens, neutralizing them or marking them for destruction by other immune cells. This helps to prevent the spread of infection and protect the body from harmful substances.

Antibody formation is an important part of the adaptive immune response, which allows the body to specifically recognize and respond to a wide variety of pathogens and foreign substances.

Adaptive immunity is a specific type of immune response that involves the activation of immune cells, such as T-lymphocytes and B-lymphocytes, to recognize and respond to specific antigens. This type of immunity is called "adaptive" because it can change over time to better recognize and respond to particular threats.

Adaptive immunity has several key features that distinguish it from innate immunity, which is the other main type of immune response. One of the most important features of adaptive immunity is its ability to specifically recognize and target individual antigens. This is made possible by the presence of special receptors on T-lymphocytes and B-lymphocytes that can bind to specific proteins or other molecules on the surface of invading pathogens.

Another key feature of adaptive immunity is its ability to "remember" previous encounters with antigens. This allows the immune system to mount a more rapid and effective response when it encounters the same antigen again in the future. This is known as immunological memory, and it is the basis for vaccination, which exposes the immune system to a harmless form of an antigen in order to stimulate the production of immunological memory and protect against future infection.

Overall, adaptive immunity plays a crucial role in protecting the body against infection and disease, and it is an essential component of the overall immune response.

Immunoglobulin G (IgG) is a type of antibody, which is a protective protein produced by the immune system in response to foreign substances like bacteria or viruses. IgG is the most abundant type of antibody in human blood, making up about 75-80% of all antibodies. It is found in all body fluids and plays a crucial role in fighting infections caused by bacteria, viruses, and toxins.

IgG has several important functions:

1. Neutralization: IgG can bind to the surface of bacteria or viruses, preventing them from attaching to and infecting human cells.
2. Opsonization: IgG coats the surface of pathogens, making them more recognizable and easier for immune cells like neutrophils and macrophages to phagocytose (engulf and destroy) them.
3. Complement activation: IgG can activate the complement system, a group of proteins that work together to help eliminate pathogens from the body. Activation of the complement system leads to the formation of the membrane attack complex, which creates holes in the cell membranes of bacteria, leading to their lysis (destruction).
4. Antibody-dependent cellular cytotoxicity (ADCC): IgG can bind to immune cells like natural killer (NK) cells and trigger them to release substances that cause target cells (such as virus-infected or cancerous cells) to undergo apoptosis (programmed cell death).
5. Immune complex formation: IgG can form immune complexes with antigens, which can then be removed from the body through various mechanisms, such as phagocytosis by immune cells or excretion in urine.

IgG is a critical component of adaptive immunity and provides long-lasting protection against reinfection with many pathogens. It has four subclasses (IgG1, IgG2, IgG3, and IgG4) that differ in their structure, function, and distribution in the body.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Interferon-gamma (IFN-γ) is a soluble cytokine that is primarily produced by the activation of natural killer (NK) cells and T lymphocytes, especially CD4+ Th1 cells and CD8+ cytotoxic T cells. It plays a crucial role in the regulation of the immune response against viral and intracellular bacterial infections, as well as tumor cells. IFN-γ has several functions, including activating macrophages to enhance their microbicidal activity, increasing the presentation of major histocompatibility complex (MHC) class I and II molecules on antigen-presenting cells, stimulating the proliferation and differentiation of T cells and NK cells, and inducing the production of other cytokines and chemokines. Additionally, IFN-γ has direct antiproliferative effects on certain types of tumor cells and can enhance the cytotoxic activity of immune cells against infected or malignant cells.

T-lymphocyte subsets refer to distinct populations of T-cells, which are a type of white blood cell that plays a central role in cell-mediated immunity. The two main types of T-lymphocytes are CD4+ and CD8+ cells, which are defined by the presence or absence of specific proteins called cluster differentiation (CD) molecules on their surface.

CD4+ T-cells, also known as helper T-cells, play a crucial role in activating other immune cells, such as B-lymphocytes and macrophages, to mount an immune response against pathogens. They also produce cytokines that help regulate the immune response.

CD8+ T-cells, also known as cytotoxic T-cells, directly kill infected cells or tumor cells by releasing toxic substances such as perforins and granzymes.

The balance between these two subsets of T-cells is critical for maintaining immune homeostasis and mounting effective immune responses against pathogens while avoiding excessive inflammation and autoimmunity. Therefore, the measurement of T-lymphocyte subsets is essential in diagnosing and monitoring various immunological disorders, including HIV infection, cancer, and autoimmune diseases.

HLA-G antigens are a type of human leukocyte antigen (HLA) class Ib molecule that plays a crucial role in the immune system. HLA molecules are responsible for presenting pieces of proteins from inside the cell to the surface, where they can be recognized by the immune system's T-cells.

HLA-G antigens are primarily expressed in fetal tissues, including trophoblast cells that make up the placenta, and are involved in protecting the fetus from rejection by the mother's immune system during pregnancy. They have also been found to have immunosuppressive effects in other contexts, such as in cancer and transplantation.

HLA-G antigens are highly polymorphic, meaning that there are many different variations or "alleles" of the HLA-G gene that can be inherited from each parent. These genetic differences can affect the structure and function of the HLA-G molecule and may have implications for disease susceptibility and immune responses.

Clonal anergy is a term used in immunology to describe a state of immune tolerance or unresponsiveness in certain T cells, a type of white blood cell that plays a central role in the body's immune response. This condition arises when T cells are exposed to persistent antigens, such as those derived from viruses or tumors, and fail to become fully activated.

In normal circumstances, when a T cell encounters an antigen presented by an antigen-presenting cell (APC), it becomes activated and undergoes clonal expansion, producing many copies of itself that are specific for that particular antigen. These activated T cells then migrate to the site of infection or tissue damage and help coordinate the immune response to eliminate the threat.

However, in some cases, persistent exposure to an antigen can lead to a state of exhaustion or anergy in the T cells, where they are no longer able to respond effectively to that antigen. This is thought to occur due to chronic stimulation and activation of the T cells, which can lead to the upregulation of inhibitory receptors and the downregulation of activating receptors on their surface.

Clonal anergy is a mechanism by which the immune system attempts to prevent excessive or inappropriate immune responses that could cause tissue damage or autoimmunity. However, it can also be a barrier to effective immunotherapy for diseases such as cancer, where T cells need to be activated and able to recognize and eliminate tumor cells.

In summary, clonal anergy is a state of immune tolerance in certain T cells that have been persistently exposed to antigens, leading to their failure to become fully activated and respond effectively to those antigens.

Skin transplantation, also known as skin grafting, is a surgical procedure that involves the removal of healthy skin from one part of the body (donor site) and its transfer to another site (recipient site) that has been damaged or lost due to various reasons such as burns, injuries, infections, or diseases. The transplanted skin can help in healing wounds, restoring functionality, and improving the cosmetic appearance of the affected area. There are different types of skin grafts, including split-thickness grafts, full-thickness grafts, and composite grafts, which vary in the depth and size of the skin removed and transplanted. The success of skin transplantation depends on various factors, including the size and location of the wound, the patient's overall health, and the availability of suitable donor sites.

Autoantibodies are defined as antibodies that are produced by the immune system and target the body's own cells, tissues, or organs. These antibodies mistakenly identify certain proteins or molecules in the body as foreign invaders and attack them, leading to an autoimmune response. Autoantibodies can be found in various autoimmune diseases such as rheumatoid arthritis, lupus, and thyroiditis. The presence of autoantibodies can also be used as a diagnostic marker for certain conditions.

Chimerism is a medical term that refers to the presence of genetically distinct cell populations within an individual. This phenomenon can occur naturally or as a result of a medical procedure such as a stem cell transplant. In natural chimerism, an individual may have cells with different genetic compositions due to events that occurred during embryonic development, such as the fusion of two fertilized eggs (also known as "twinning") or the exchange of cells between twins in utero.

In the context of a stem cell transplant, chimerism can occur when a donor's stem cells engraft and begin to produce new blood cells in the recipient's body. This can result in the presence of both the recipient's own cells and the donor's cells in the recipient's body. The degree of chimerism can vary, with some individuals showing complete chimerism (where all blood cells are derived from the donor) or mixed chimerism (where both the recipient's and donor's cells coexist).

Monitoring chimerism levels is important in stem cell transplantation to assess the success of the procedure and to detect any potential signs of graft rejection or relapse of the original disease.

Animal disease models are specialized animals, typically rodents such as mice or rats, that have been genetically engineered or exposed to certain conditions to develop symptoms and physiological changes similar to those seen in human diseases. These models are used in medical research to study the pathophysiology of diseases, identify potential therapeutic targets, test drug efficacy and safety, and understand disease mechanisms.

The genetic modifications can include knockout or knock-in mutations, transgenic expression of specific genes, or RNA interference techniques. The animals may also be exposed to environmental factors such as chemicals, radiation, or infectious agents to induce the disease state.

Examples of animal disease models include:

1. Mouse models of cancer: Genetically engineered mice that develop various types of tumors, allowing researchers to study cancer initiation, progression, and metastasis.
2. Alzheimer's disease models: Transgenic mice expressing mutant human genes associated with Alzheimer's disease, which exhibit amyloid plaque formation and cognitive decline.
3. Diabetes models: Obese and diabetic mouse strains like the NOD (non-obese diabetic) or db/db mice, used to study the development of type 1 and type 2 diabetes, respectively.
4. Cardiovascular disease models: Atherosclerosis-prone mice, such as ApoE-deficient or LDLR-deficient mice, that develop plaque buildup in their arteries when fed a high-fat diet.
5. Inflammatory bowel disease models: Mice with genetic mutations affecting intestinal barrier function and immune response, such as IL-10 knockout or SAMP1/YitFc mice, which develop colitis.

Animal disease models are essential tools in preclinical research, but it is important to recognize their limitations. Differences between species can affect the translatability of results from animal studies to human patients. Therefore, researchers must carefully consider the choice of model and interpret findings cautiously when applying them to human diseases.

Immunization is defined medically as the process where an individual is made immune or resistant to an infectious disease, typically through the administration of a vaccine. The vaccine stimulates the body's own immune system to recognize and fight off the specific disease-causing organism, thereby preventing or reducing the severity of future infections with that organism.

Immunization can be achieved actively, where the person is given a vaccine to trigger an immune response, or passively, where antibodies are transferred to the person through immunoglobulin therapy. Immunizations are an important part of preventive healthcare and have been successful in controlling and eliminating many infectious diseases worldwide.

Ovalbumin is the major protein found in egg white, making up about 54-60% of its total protein content. It is a glycoprotein with a molecular weight of around 45 kDa and has both hydrophilic and hydrophobic regions. Ovalbumin is a single polypeptide chain consisting of 385 amino acids, including four disulfide bridges that contribute to its structure.

Ovalbumin is often used in research as a model antigen for studying immune responses and allergies. In its native form, ovalbumin is not allergenic; however, when it is denatured or degraded into smaller peptides through cooking or digestion, it can become an allergen for some individuals.

In addition to being a food allergen, ovalbumin has been used in various medical and research applications, such as vaccine development, immunological studies, and protein structure-function analysis.

Antigen-presenting cells (APCs) are a group of specialized cells in the immune system that play a critical role in initiating and regulating immune responses. They have the ability to engulf, process, and present antigens (molecules derived from pathogens or other foreign substances) on their surface in conjunction with major histocompatibility complex (MHC) molecules. This presentation of antigens allows APCs to activate T cells, which are crucial for adaptive immunity.

There are several types of APCs, including:

1. Dendritic cells (DCs): These are the most potent and professional APCs, found in various tissues throughout the body. DCs can capture antigens from their environment, process them, and migrate to lymphoid organs where they present antigens to T cells.
2. Macrophages: These large phagocytic cells are found in many tissues and play a role in both innate and adaptive immunity. They can engulf and digest pathogens, then present processed antigens on their MHC class II molecules to activate CD4+ T helper cells.
3. B cells: These are primarily responsible for humoral immune responses by producing antibodies against antigens. When activated, B cells can also function as APCs and present antigens on their MHC class II molecules to CD4+ T cells.

The interaction between APCs and T cells is critical for the development of an effective immune response against pathogens or other foreign substances. This process helps ensure that the immune system can recognize and eliminate threats while minimizing damage to healthy tissues.

Immunomodulation is the process of modifying or regulating the immune system's response. It can involve either stimulating or suppressing various components of the immune system, such as white blood cells, antibodies, or cytokines. This can be achieved through various means, including medications (such as immunosuppressive drugs used in organ transplantation), vaccines, and other therapies.

The goal of immunomodulation is to restore balance to an overactive or underactive immune system, depending on the specific medical condition being treated. It can help to prevent or treat diseases that result from abnormal immune responses, such as autoimmune disorders, allergies, and infections.

Heterophile antigens are a type of antigen that can induce an immune response in multiple species, not just the one they originate from. They are called "heterophile" because they exhibit cross-reactivity with antibodies produced against different antigens from other species. A common example of heterophile antigens is the Forssman antigen, which can be found in various animals such as guinea pigs, rabbits, and humans.

Heterophile antibody tests are often used in diagnostic medicine to detect certain infections or autoimmune disorders. One well-known example is the Paul-Bunnell test, which was historically used to diagnose infectious mononucleosis (IM) caused by the Epstein-Barr virus (EBV). The test detects heterophile antibodies produced against EBV antigens that cross-react with sheep red blood cells. However, this test has been largely replaced by more specific and sensitive EBV antibody tests.

It is important to note that heterophile antibody tests can sometimes produce false positive results due to the presence of these cross-reactive antibodies in individuals who have not been infected with the targeted pathogen. Therefore, it is crucial to interpret test results cautiously and consider them alongside clinical symptoms, medical history, and other diagnostic findings.

CD (cluster of differentiation) antigens are cell-surface proteins that are expressed on leukocytes (white blood cells) and can be used to identify and distinguish different subsets of these cells. They are important markers in the field of immunology and hematology, and are commonly used to diagnose and monitor various diseases, including cancer, autoimmune disorders, and infectious diseases.

CD antigens are designated by numbers, such as CD4, CD8, CD19, etc., which refer to specific proteins found on the surface of different types of leukocytes. For example, CD4 is a protein found on the surface of helper T cells, while CD8 is found on cytotoxic T cells.

CD antigens can be used as targets for immunotherapy, such as monoclonal antibody therapy, in which antibodies are designed to bind to specific CD antigens and trigger an immune response against cancer cells or infected cells. They can also be used as markers to monitor the effectiveness of treatments and to detect minimal residual disease (MRD) after treatment.

It's important to note that not all CD antigens are exclusive to leukocytes, some can be found on other cell types as well, and their expression can vary depending on the activation state or differentiation stage of the cells.

Factor IX is also known as Christmas factor, which is a protein that plays a crucial role in the coagulation cascade, a series of chemical reactions that leads to the formation of a blood clot. It is one of the essential components required for the proper functioning of the body's natural blood-clotting mechanism.

Factor IX is synthesized in the liver and activated when it comes into contact with an injured blood vessel. Once activated, it collaborates with other factors to convert factor X to its active form, which then converts prothrombin to thrombin. Thrombin is responsible for converting fibrinogen to fibrin, forming a stable fibrin clot that helps stop bleeding and promote healing.

Deficiencies in Factor IX can lead to hemophilia B, a genetic disorder characterized by prolonged bleeding and an increased risk of spontaneous bleeding. Hemophilia B is inherited in an X-linked recessive pattern, meaning it primarily affects males, while females serve as carriers of the disease. Treatment for hemophilia B typically involves replacing the missing or deficient Factor IX through infusions to prevent or manage bleeding episodes.

Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.

The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.

Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

Clonal deletion is a process in the immune system where T cells or B cells that have receptors which are highly reactive to self-antigens are eliminated during development in the thymus or bone marrow, respectively. This helps prevent the development of autoimmune diseases, where the immune system attacks the body's own tissues and organs.

During the development of T cells in the thymus, immature T cells undergo a selection process to ensure that they do not react strongly to self-antigens. Those that do are eliminated through a process called negative selection or clonal deletion. Similarly, developing B cells in the bone marrow that produce antibodies with high affinity for self-antigens are also deleted.

Clonal deletion is an essential mechanism for maintaining self-tolerance and preventing the development of autoimmune diseases. However, if this process fails or is impaired, it can lead to the development of autoimmunity.

Heterotopic transplantation is a type of organ or tissue transplant where the graft is placed in a different location from where it normally resides while still maintaining its original site. This is often done to supplement the function of the existing organ rather than replacing it. A common example of heterotopic transplantation is a heart transplant, where the donor's heart is placed in a new location in the recipient's body, while the recipient's own heart remains in place but is typically nonfunctional. This allows for the possibility of returning the function of the recipient's heart if the transplanted organ fails.

In heterotopic kidney transplantation, the donor kidney is placed in a different location, usually in the lower abdomen, while the recipient's own kidneys are left in place. This approach can be beneficial for recipients with poor renal function or other medical conditions that make traditional kidney transplantation too risky.

Heterotopic transplantation is also used in liver transplantation, where a portion of the donor liver is placed in a different location, typically in the recipient's abdomen, while the recipient's own liver remains in place. This approach can be useful for recipients with acute liver failure or other conditions that make traditional liver transplantation too risky.

One advantage of heterotopic transplantation is that it allows for the possibility of returning the function of the recipient's organ if the transplanted organ fails, as well as reducing the risk of rejection and improving overall outcomes for the recipient. However, this approach also has some disadvantages, such as increased complexity of the surgical procedure, potential for complications related to the placement of the graft, and the need for ongoing immunosuppression therapy to prevent rejection.

The thymus gland is an essential organ of the immune system, located in the upper chest, behind the sternum and surrounding the heart. It's primarily active until puberty and begins to shrink in size and activity thereafter. The main function of the thymus gland is the production and maturation of T-lymphocytes (T-cells), which are crucial for cell-mediated immunity, helping to protect the body from infection and cancer.

The thymus gland provides a protected environment where immune cells called pre-T cells develop into mature T cells. During this process, they learn to recognize and respond appropriately to foreign substances while remaining tolerant to self-tissues, which is crucial for preventing autoimmune diseases.

Additionally, the thymus gland produces hormones like thymosin that regulate immune cell activities and contribute to the overall immune response.

Leukocyte transfusion, also known as white blood cell (WBC) transfusion, involves the intravenous administration of leukocytes (white blood cells) from a donor to a recipient. This procedure is typically used in patients with severe immunodeficiency or those undergoing bone marrow transplantation, where they are unable to produce sufficient white blood cells to fight off infections.

Leukocyte transfusions can help boost the recipient's immune system and provide them with temporary protection against infections. However, this procedure carries some risks, including febrile non-hemolytic transfusion reactions, allergic reactions, transmission of infectious diseases, and the potential for transfusion-associated graft-versus-host disease (TA-GVHD). Therefore, leukocyte transfusions are usually reserved for specific clinical situations where the benefits outweigh the risks.

Inbred NOD (Nonobese Diabetic) mice are a strain of laboratory mice that are genetically predisposed to develop autoimmune diabetes. This strain was originally developed in Japan and has been widely used as an animal model for studying type 1 diabetes and its complications.

NOD mice typically develop diabetes spontaneously at around 12-14 weeks of age, although the onset and severity of the disease can vary between individual mice. The disease is caused by a breakdown in immune tolerance, leading to an autoimmune attack on the insulin-producing beta cells of the pancreas.

Inbred NOD mice are highly valuable for research purposes because they exhibit many of the same genetic and immunological features as human patients with type 1 diabetes. By studying these mice, researchers can gain insights into the underlying mechanisms of the disease and develop new treatments and therapies.

Graft rejection is an immune response that occurs when transplanted tissue or organ (the graft) is recognized as foreign by the recipient's immune system, leading to the activation of immune cells to attack and destroy the graft. This results in the failure of the transplant and the need for additional medical intervention or another transplant. There are three types of graft rejection: hyperacute, acute, and chronic. Hyperacute rejection occurs immediately or soon after transplantation due to pre-existing antibodies against the graft. Acute rejection typically occurs within weeks to months post-transplant and is characterized by the infiltration of T-cells into the graft. Chronic rejection, which can occur months to years after transplantation, is a slow and progressive process characterized by fibrosis and tissue damage due to ongoing immune responses against the graft.

An Enzyme-Linked Immunosorbent Assay (ELISA) is a type of analytical biochemistry assay used to detect and quantify the presence of a substance, typically a protein or peptide, in a liquid sample. It takes its name from the enzyme-linked antibodies used in the assay.

In an ELISA, the sample is added to a well containing a surface that has been treated to capture the target substance. If the target substance is present in the sample, it will bind to the surface. Next, an enzyme-linked antibody specific to the target substance is added. This antibody will bind to the captured target substance if it is present. After washing away any unbound material, a substrate for the enzyme is added. If the enzyme is present due to its linkage to the antibody, it will catalyze a reaction that produces a detectable signal, such as a color change or fluorescence. The intensity of this signal is proportional to the amount of target substance present in the sample, allowing for quantification.

ELISAs are widely used in research and clinical settings to detect and measure various substances, including hormones, viruses, and bacteria. They offer high sensitivity, specificity, and reproducibility, making them a reliable choice for many applications.

Immunological models are simplified representations or simulations of the immune system's structure, function, and interactions with pathogens or other entities. These models can be theoretical (conceptual), mathematical, or computational and are used to understand, explain, and predict immunological phenomena. They help researchers study complex immune processes and responses that cannot be easily observed or manipulated in vivo.

Theoretical immunological models provide conceptual frameworks for understanding immune system behavior, often using diagrams or flowcharts to illustrate interactions between immune components. Mathematical models use mathematical equations to describe immune system dynamics, allowing researchers to simulate and analyze the outcomes of various scenarios. Computational models, also known as in silico models, are created using computer software and can incorporate both theoretical and mathematical concepts to create detailed simulations of immunological processes.

Immunological models are essential tools for advancing our understanding of the immune system and developing new therapies and vaccines. They enable researchers to test hypotheses, explore the implications of different assumptions, and identify areas requiring further investigation.

I could not find a specific medical definition for "Vaccines, DNA." However, I can provide you with some information about DNA vaccines.

DNA vaccines are a type of vaccine that uses genetically engineered DNA to stimulate an immune response in the body. They work by introducing a small piece of DNA into the body that contains the genetic code for a specific antigen (a substance that triggers an immune response). The cells of the body then use this DNA to produce the antigen, which prompts the immune system to recognize and attack it.

DNA vaccines have several advantages over traditional vaccines. They are relatively easy to produce, can be stored at room temperature, and can be designed to protect against a wide range of diseases. Additionally, because they use DNA to stimulate an immune response, DNA vaccines do not require the growth and culture of viruses or bacteria, which can make them safer than traditional vaccines.

DNA vaccines are still in the experimental stages, and more research is needed to determine their safety and effectiveness. However, they have shown promise in animal studies and are being investigated as a potential tool for preventing a variety of infectious diseases, including influenza, HIV, and cancer.

Diabetes Mellitus, Type 1 is a chronic autoimmune disease characterized by the destruction of insulin-producing beta cells in the pancreas, leading to an absolute deficiency of insulin. This results in an inability to regulate blood glucose levels, causing hyperglycemia (high blood sugar). Type 1 diabetes typically presents in childhood or early adulthood, although it can develop at any age. It is usually managed with regular insulin injections or the use of an insulin pump, along with monitoring of blood glucose levels and adjustments to diet and physical activity. Uncontrolled type 1 diabetes can lead to serious complications such as kidney damage, nerve damage, blindness, and cardiovascular disease.

Immune evasion is a term used in immunology to describe the various strategies employed by pathogens (such as viruses, bacteria, parasites) to avoid or subvert the host's immune system. This can include mechanisms that allow the pathogen to directly inhibit or escape the actions of immune cells, like T cells and neutrophils, or to prevent the detection of their presence by masking themselves from the immune system.

For example, some viruses may change their surface proteins to avoid recognition by antibodies, while others may block the presentation of their antigens to T cells. Similarly, some bacteria can produce enzymes that degrade or modify components of the immune system, allowing them to evade detection and destruction.

Immune evasion is a major challenge in the development of effective vaccines and therapies for infectious diseases, as it allows pathogens to persist and cause chronic infections. Understanding the mechanisms of immune evasion can help researchers develop strategies to overcome these challenges and improve outcomes for patients.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

Delayed hypersensitivity, also known as type IV hypersensitivity, is a type of immune response that takes place several hours to days after exposure to an antigen. It is characterized by the activation of T cells (a type of white blood cell) and the release of various chemical mediators, leading to inflammation and tissue damage. This reaction is typically associated with chronic inflammatory diseases, such as contact dermatitis, granulomatous disorders (e.g. tuberculosis), and certain autoimmune diseases.

The reaction process involves the following steps:

1. Sensitization: The first time an individual is exposed to an antigen, T cells are activated and become sensitized to it. This process can take several days.
2. Memory: Some of the activated T cells differentiate into memory T cells, which remain in the body and are ready to respond quickly if the same antigen is encountered again.
3. Effector phase: Upon subsequent exposure to the antigen, the memory T cells become activated and release cytokines, which recruit other immune cells (e.g. macrophages) to the site of inflammation. These cells cause tissue damage through various mechanisms, such as phagocytosis, degranulation, and the release of reactive oxygen species.
4. Chronic inflammation: The ongoing immune response can lead to chronic inflammation, which may result in tissue destruction and fibrosis (scarring).

Examples of conditions associated with delayed hypersensitivity include:

* Contact dermatitis (e.g. poison ivy, nickel allergy)
* Tuberculosis
* Leprosy
* Sarcoidosis
* Rheumatoid arthritis
* Type 1 diabetes mellitus
* Multiple sclerosis
* Inflammatory bowel disease (e.g. Crohn's disease, ulcerative colitis)

A transplantation chimera is a rare medical condition that occurs after an organ or tissue transplant, where the recipient's body accepts and integrates the donor's cells or tissues to such an extent that the two sets of DNA coexist and function together. This phenomenon can lead to the presence of two different genetic profiles in one individual.

In some cases, this may result in the development of donor-derived cells or organs within the recipient's body, which can express the donor's unique genetic traits. Transplantation chimerism is more commonly observed in bone marrow transplants, where the donor's immune cells can repopulate and establish themselves within the recipient's bone marrow and bloodstream.

It is important to note that while transplantation chimerism can be beneficial for the success of the transplant, it may also pose some risks, such as an increased likelihood of developing graft-versus-host disease (GVHD), where the donor's immune cells attack the recipient's tissues.

Antigen presentation is the process by which certain cells in the immune system, known as antigen presenting cells (APCs), display foreign or abnormal proteins (antigens) on their surface to other immune cells, such as T-cells. This process allows the immune system to recognize and mount a response against harmful pathogens, infected or damaged cells.

There are two main types of antigen presentation: major histocompatibility complex (MHC) class I and MHC class II presentation.

1. MHC class I presentation: APCs, such as dendritic cells, macrophages, and B-cells, process and load antigens onto MHC class I molecules, which are expressed on the surface of almost all nucleated cells in the body. The MHC class I-antigen complex is then recognized by CD8+ T-cells (cytotoxic T-cells), leading to the destruction of infected or damaged cells.
2. MHC class II presentation: APCs, particularly dendritic cells and B-cells, process and load antigens onto MHC class II molecules, which are mainly expressed on the surface of professional APCs. The MHC class II-antigen complex is then recognized by CD4+ T-cells (helper T-cells), leading to the activation of other immune cells, such as B-cells and macrophages, to eliminate the pathogen or damaged cells.

In summary, antigen presentation is a crucial step in the adaptive immune response, allowing for the recognition and elimination of foreign or abnormal substances that could potentially harm the body.

CD8-positive T-lymphocytes, also known as CD8+ T cells or cytotoxic T cells, are a type of white blood cell that plays a crucial role in the adaptive immune system. They are named after the CD8 molecule found on their surface, which is a protein involved in cell signaling and recognition.

CD8+ T cells are primarily responsible for identifying and destroying virus-infected cells or cancerous cells. When activated, they release cytotoxic granules that contain enzymes capable of inducing apoptosis (programmed cell death) in the target cells. They also produce cytokines such as interferon-gamma, which can help coordinate the immune response and activate other immune cells.

CD8+ T cells are generated in the thymus gland and are a type of T cell, which is a lymphocyte that matures in the thymus and plays a central role in cell-mediated immunity. They recognize and respond to specific antigens presented on the surface of infected or cancerous cells in conjunction with major histocompatibility complex (MHC) class I molecules.

Overall, CD8+ T cells are an essential component of the immune system's defense against viral infections and cancer.

Homologous transplantation is a type of transplant surgery where organs or tissues are transferred between two genetically non-identical individuals of the same species. The term "homologous" refers to the similarity in structure and function of the donated organ or tissue to the recipient's own organ or tissue.

For example, a heart transplant from one human to another is an example of homologous transplantation because both organs are hearts and perform the same function. Similarly, a liver transplant, kidney transplant, lung transplant, and other types of organ transplants between individuals of the same species are also considered homologous transplantations.

Homologous transplantation is in contrast to heterologous or xenogeneic transplantation, where organs or tissues are transferred from one species to another, such as a pig heart transplanted into a human. Homologous transplantation is more commonly performed than heterologous transplantation due to the increased risk of rejection and other complications associated with xenogeneic transplants.

Th1 cells, or Type 1 T helper cells, are a subset of CD4+ T cells that play a crucial role in the cell-mediated immune response. They are characterized by the production of specific cytokines, such as interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), and interleukin-2 (IL-2). Th1 cells are essential for protecting against intracellular pathogens, including viruses, bacteria, and parasites. They activate macrophages to destroy ingested microorganisms, stimulate the differentiation of B cells into plasma cells that produce antibodies, and recruit other immune cells to the site of infection. Dysregulation of Th1 cell responses has been implicated in various autoimmune diseases, such as multiple sclerosis, rheumatoid arthritis, and type 1 diabetes.

'Immune sera' refers to the serum fraction of blood that contains antibodies produced in response to an antigenic stimulus, such as a vaccine or an infection. These antibodies are proteins known as immunoglobulins, which are secreted by B cells (a type of white blood cell) and can recognize and bind to specific antigens. Immune sera can be collected from an immunized individual and used as a source of passive immunity to protect against infection or disease. It is often used in research and diagnostic settings to identify or measure the presence of specific antigens or antibodies.

An antigen-antibody complex is a type of immune complex that forms when an antibody binds to a specific antigen. An antigen is any substance that triggers an immune response, while an antibody is a protein produced by the immune system to neutralize or destroy foreign substances like antigens.

When an antibody binds to an antigen, it forms a complex that can be either soluble or insoluble. Soluble complexes are formed when the antigen is small and can move freely through the bloodstream. Insoluble complexes, on the other hand, are formed when the antigen is too large to move freely, such as when it is part of a bacterium or virus.

The formation of antigen-antibody complexes plays an important role in the immune response. Once formed, these complexes can be recognized and cleared by other components of the immune system, such as phagocytes, which help to prevent further damage to the body. However, in some cases, the formation of large numbers of antigen-antibody complexes can lead to inflammation and tissue damage, contributing to the development of certain autoimmune diseases.

Mucosal immunity refers to the immune system's defense mechanisms that are specifically adapted to protect the mucous membranes, which line various body openings such as the respiratory, gastrointestinal, and urogenital tracts. These membranes are constantly exposed to foreign substances, including potential pathogens, and therefore require a specialized immune response to maintain homeostasis and prevent infection.

Mucosal immunity is primarily mediated by secretory IgA (SIgA) antibodies, which are produced by B cells in the mucosa-associated lymphoid tissue (MALT). These antibodies can neutralize pathogens and prevent them from adhering to and invading the epithelial cells that line the mucous membranes.

In addition to SIgA, other components of the mucosal immune system include innate immune cells such as macrophages, dendritic cells, and neutrophils, which can recognize and respond to pathogens through pattern recognition receptors (PRRs). T cells also play a role in mucosal immunity, particularly in the induction of cell-mediated immunity against viruses and other intracellular pathogens.

Overall, mucosal immunity is an essential component of the body's defense system, providing protection against a wide range of potential pathogens while maintaining tolerance to harmless antigens present in the environment.

Graft survival, in medical terms, refers to the success of a transplanted tissue or organ in continuing to function and integrate with the recipient's body over time. It is the opposite of graft rejection, which occurs when the recipient's immune system recognizes the transplanted tissue as foreign and attacks it, leading to its failure.

Graft survival depends on various factors, including the compatibility between the donor and recipient, the type and location of the graft, the use of immunosuppressive drugs to prevent rejection, and the overall health of the recipient. A successful graft survival implies that the transplanted tissue or organ has been accepted by the recipient's body and is functioning properly, providing the necessary physiological support for the recipient's survival and improved quality of life.

Inflammation is a complex biological response of tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. It is characterized by the following signs: rubor (redness), tumor (swelling), calor (heat), dolor (pain), and functio laesa (loss of function). The process involves the activation of the immune system, recruitment of white blood cells, and release of inflammatory mediators, which contribute to the elimination of the injurious stimuli and initiation of the healing process. However, uncontrolled or chronic inflammation can also lead to tissue damage and diseases.

Lymph nodes are small, bean-shaped organs that are part of the immune system. They are found throughout the body, especially in the neck, armpits, groin, and abdomen. Lymph nodes filter lymph fluid, which carries waste and unwanted substances such as bacteria, viruses, and cancer cells. They contain white blood cells called lymphocytes that help fight infections and diseases by attacking and destroying the harmful substances found in the lymph fluid. When an infection or disease is present, lymph nodes may swell due to the increased number of immune cells and fluid accumulation as they work to fight off the invaders.

Antibodies are proteins produced by the immune system in response to the presence of a foreign substance, such as a bacterium or virus. They are capable of identifying and binding to specific antigens (foreign substances) on the surface of these invaders, marking them for destruction by other immune cells. Antibodies are also known as immunoglobulins and come in several different types, including IgA, IgD, IgE, IgG, and IgM, each with a unique function in the immune response. They are composed of four polypeptide chains, two heavy chains and two light chains, that are held together by disulfide bonds. The variable regions of the heavy and light chains form the antigen-binding site, which is specific to a particular antigen.

Desensitization, Immunologic is a medical procedure that aims to decrease the immune system's response to an allergen. This is achieved through the controlled exposure of the patient to gradually increasing amounts of the allergen, ultimately leading to a reduction in the severity of allergic reactions upon subsequent exposures. The process typically involves administering carefully measured and incrementally larger doses of the allergen, either orally, sublingually (under the tongue), or by injection, under medical supervision. Over time, this repeated exposure can help the immune system become less sensitive to the allergen, thereby alleviating allergic symptoms.

The specific desensitization protocol and administration method may vary depending on the type of allergen and individual patient factors. Immunologic desensitization is most commonly used for environmental allergens like pollen, dust mites, or pet dander, as well as insect venoms such as bee or wasp stings. It is important to note that this procedure should only be performed under the close supervision of a qualified healthcare professional, as there are potential risks involved, including anaphylaxis (a severe and life-threatening allergic reaction).

Isoantigens are antigens that are present on the cells or tissues of one individual of a species, but are absent or different in another individual of the same species. They are also known as "alloantigens." Isoantigens are most commonly found on the surface of red blood cells and other tissues, and they can stimulate an immune response when transplanted into a different individual. This is because the recipient's immune system recognizes the isoantigens as foreign and mounts a defense against them. Isoantigens are important in the field of transplantation medicine, as they must be carefully matched between donor and recipient to reduce the risk of rejection.

"Tumor escape" is not a widely recognized medical term with a specific definition. However, in the context of cancer biology and immunotherapy, "tumor escape" refers to the ability of cancer cells to evade or suppress the immune system's response, allowing the tumor to continue growing and spreading. This can occur through various mechanisms, such as downregulation of major histocompatibility complex (MHC) molecules, production of immunosuppressive cytokines, recruitment of regulatory T cells, or induction of apoptosis in immune effector cells. Understanding the mechanisms of tumor escape is crucial for developing more effective cancer treatments and improving patient outcomes.

Cell proliferation is the process by which cells increase in number, typically through the process of cell division. In the context of biology and medicine, it refers to the reproduction of cells that makes up living tissue, allowing growth, maintenance, and repair. It involves several stages including the transition from a phase of quiescence (G0 phase) to an active phase (G1 phase), DNA replication in the S phase, and mitosis or M phase, where the cell divides into two daughter cells.

Abnormal or uncontrolled cell proliferation is a characteristic feature of many diseases, including cancer, where deregulated cell cycle control leads to excessive and unregulated growth of cells, forming tumors that can invade surrounding tissues and metastasize to distant sites in the body.

'C3H' is the name of an inbred strain of laboratory mice that was developed at the Jackson Laboratory in Bar Harbor, Maine. The mice are characterized by their uniform genetic background and have been widely used in biomedical research for many decades.

The C3H strain is particularly notable for its susceptibility to certain types of cancer, including mammary tumors and lymphomas. It also has a high incidence of age-related macular degeneration and other eye diseases. The strain is often used in studies of immunology, genetics, and carcinogenesis.

Like all inbred strains, the C3H mice are the result of many generations of brother-sister matings, which leads to a high degree of genetic uniformity within the strain. This makes them useful for studying the effects of specific genes or environmental factors on disease susceptibility and other traits. However, it also means that they may not always be representative of the genetic diversity found in outbred populations, including humans.

'Gene expression regulation' refers to the processes that control whether, when, and where a particular gene is expressed, meaning the production of a specific protein or functional RNA encoded by that gene. This complex mechanism can be influenced by various factors such as transcription factors, chromatin remodeling, DNA methylation, non-coding RNAs, and post-transcriptional modifications, among others. Proper regulation of gene expression is crucial for normal cellular function, development, and maintaining homeostasis in living organisms. Dysregulation of gene expression can lead to various diseases, including cancer and genetic disorders.

Glucose intolerance is a condition in which the body has difficulty processing and using glucose, or blood sugar, effectively. This results in higher than normal levels of glucose in the blood after eating, particularly after meals that are high in carbohydrates. Glucose intolerance can be an early sign of developing diabetes, specifically type 2 diabetes, and it may also indicate other metabolic disorders such as prediabetes or insulin resistance.

In a healthy individual, the pancreas produces insulin to help regulate blood sugar levels by facilitating glucose uptake in muscles, fat tissue, and the liver. When someone has glucose intolerance, their body may not produce enough insulin, or their cells may have become less responsive to insulin (insulin resistance), leading to impaired glucose metabolism.

Glucose intolerance can be diagnosed through various tests, including the oral glucose tolerance test (OGTT) and hemoglobin A1c (HbA1c) test. Treatment for glucose intolerance often involves lifestyle modifications such as weight loss, increased physical activity, and a balanced diet with reduced sugar and refined carbohydrate intake. In some cases, medication may be prescribed to help manage blood sugar levels more effectively.

Pregnancy is a physiological state or condition where a fertilized egg (zygote) successfully implants and grows in the uterus of a woman, leading to the development of an embryo and finally a fetus. This process typically spans approximately 40 weeks, divided into three trimesters, and culminates in childbirth. Throughout this period, numerous hormonal and physical changes occur to support the growing offspring, including uterine enlargement, breast development, and various maternal adaptations to ensure the fetus's optimal growth and well-being.

CTLA-4 (Cytotoxic T-Lymphocyte Associated Protein 4) antigen is a type of protein found on the surface of activated T cells, which are a type of white blood cell in the immune system. CTLA-4 plays an important role in regulating the immune response by functioning as a negative regulator of T cell activation.

CTLA-4 binds to CD80 and CD86 molecules on the surface of antigen-presenting cells, which are cells that display foreign antigens to T cells and activate them. By binding to these molecules, CTLA-4 inhibits T cell activation and helps prevent an overactive immune response.

CTLA-4 is a target for cancer immunotherapy because blocking its function can enhance the anti-tumor immune response. Certain drugs called checkpoint inhibitors work by blocking CTLA-4, allowing T cells to remain active and attack tumor cells more effectively.

Cell differentiation is the process by which a less specialized cell, or stem cell, becomes a more specialized cell type with specific functions and structures. This process involves changes in gene expression, which are regulated by various intracellular signaling pathways and transcription factors. Differentiation results in the development of distinct cell types that make up tissues and organs in multicellular organisms. It is a crucial aspect of embryonic development, tissue repair, and maintenance of homeostasis in the body.

Transplantation Immunology is a branch of medicine that deals with the immune responses occurring between a transplanted organ or tissue and the recipient's body. It involves understanding and managing the immune system's reaction to foreign tissue, which can lead to rejection of the transplanted organ. This field also studies the use of immunosuppressive drugs to prevent rejection and the potential risks and side effects associated with their use. The main goal of transplantation immunology is to find ways to promote the acceptance of transplanted tissue while minimizing the risk of infection and other complications.

Immunity, in medical terms, refers to the body's ability to resist or fight against harmful foreign substances or organisms such as bacteria, viruses, parasites, and fungi. This resistance is achieved through various mechanisms, including the production of antibodies, the activation of immune cells like T-cells and B-cells, and the release of cytokines and other chemical messengers that help coordinate the immune response.

There are two main types of immunity: innate immunity and adaptive immunity. Innate immunity is the body's first line of defense against infection and involves nonspecific mechanisms such as physical barriers (e.g., skin and mucous membranes), chemical barriers (e.g., stomach acid and enzymes), and inflammatory responses. Adaptive immunity, on the other hand, is specific to particular pathogens and involves the activation of T-cells and B-cells, which recognize and remember specific antigens (foreign substances that trigger an immune response). This allows the body to mount a more rapid and effective response to subsequent exposures to the same pathogen.

Immunity can be acquired through natural means, such as when a person recovers from an infection and develops immunity to that particular pathogen, or artificially, through vaccination. Vaccines contain weakened or inactivated forms of a pathogen or its components, which stimulate the immune system to produce a response without causing the disease. This response provides protection against future infections with that same pathogen.

An epitope is a specific region on the surface of an antigen (a molecule that can trigger an immune response) that is recognized by an antibody, B-cell receptor, or T-cell receptor. It is also commonly referred to as an antigenic determinant. Epitopes are typically composed of linear amino acid sequences or conformational structures made up of discontinuous amino acids in the antigen. They play a crucial role in the immune system's ability to differentiate between self and non-self molecules, leading to the targeted destruction of foreign substances like viruses and bacteria. Understanding epitopes is essential for developing vaccines, diagnostic tests, and immunotherapies.

Heart transplantation is a surgical procedure where a diseased, damaged, or failing heart is removed and replaced with a healthy donor heart. This procedure is usually considered as a last resort for patients with end-stage heart failure or severe coronary artery disease who have not responded to other treatments. The donor heart typically comes from a brain-dead individual whose family has agreed to donate their loved one's organs for transplantation. Heart transplantation is a complex and highly specialized procedure that requires a multidisciplinary team of healthcare professionals, including cardiologists, cardiac surgeons, anesthesiologists, perfusionists, nurses, and other support staff. The success rates for heart transplantation have improved significantly over the past few decades, with many patients experiencing improved quality of life and increased survival rates. However, recipients of heart transplants require lifelong immunosuppressive therapy to prevent rejection of the donor heart, which can increase the risk of infections and other complications.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Immunosuppressive agents are medications that decrease the activity of the immune system. They are often used to prevent the rejection of transplanted organs and to treat autoimmune diseases, where the immune system mistakenly attacks the body's own tissues. These drugs work by interfering with the immune system's normal responses, which helps to reduce inflammation and damage to tissues. However, because they suppress the immune system, people who take immunosuppressive agents are at increased risk for infections and other complications. Examples of immunosuppressive agents include corticosteroids, azathioprine, cyclophosphamide, mycophenolate mofetil, tacrolimus, and sirolimus.

Monoclonal antibodies are a type of antibody that are identical because they are produced by a single clone of cells. They are laboratory-produced molecules that act like human antibodies in the immune system. They can be designed to attach to specific proteins found on the surface of cancer cells, making them useful for targeting and treating cancer. Monoclonal antibodies can also be used as a therapy for other diseases, such as autoimmune disorders and inflammatory conditions.

Monoclonal antibodies are produced by fusing a single type of immune cell, called a B cell, with a tumor cell to create a hybrid cell, or hybridoma. This hybrid cell is then able to replicate indefinitely, producing a large number of identical copies of the original antibody. These antibodies can be further modified and engineered to enhance their ability to bind to specific targets, increase their stability, and improve their effectiveness as therapeutic agents.

Monoclonal antibodies have several mechanisms of action in cancer therapy. They can directly kill cancer cells by binding to them and triggering an immune response. They can also block the signals that promote cancer growth and survival. Additionally, monoclonal antibodies can be used to deliver drugs or radiation directly to cancer cells, increasing the effectiveness of these treatments while minimizing their side effects on healthy tissues.

Monoclonal antibodies have become an important tool in modern medicine, with several approved for use in cancer therapy and other diseases. They are continuing to be studied and developed as a promising approach to treating a wide range of medical conditions.

Isoantibodies are antibodies produced by the immune system that recognize and react to antigens (markers) found on the cells or tissues of another individual of the same species. These antigens are typically proteins or carbohydrates present on the surface of red blood cells, but they can also be found on other cell types.

Isoantibodies are formed when an individual is exposed to foreign antigens, usually through blood transfusions, pregnancy, or tissue transplantation. The exposure triggers the immune system to produce specific antibodies against these antigens, which can cause a harmful immune response if the individual receives another transfusion or transplant from the same donor in the future.

There are two main types of isoantibodies:

1. Agglutinins: These are IgM antibodies that cause red blood cells to clump together (agglutinate) when mixed with the corresponding antigen. They develop rapidly after exposure and can cause immediate transfusion reactions or hemolytic disease of the newborn in pregnant women.
2. Hemolysins: These are IgG antibodies that destroy red blood cells by causing their membranes to become more permeable, leading to lysis (bursting) of the cells and release of hemoglobin into the plasma. They take longer to develop but can cause delayed transfusion reactions or hemolytic disease of the newborn in pregnant women.

Isoantibodies are detected through blood tests, such as the crossmatch test, which determines compatibility between a donor's and recipient's blood before transfusions or transplants.

Macrophages are a type of white blood cell that are an essential part of the immune system. They are large, specialized cells that engulf and destroy foreign substances, such as bacteria, viruses, parasites, and fungi, as well as damaged or dead cells. Macrophages are found throughout the body, including in the bloodstream, lymph nodes, spleen, liver, lungs, and connective tissues. They play a critical role in inflammation, immune response, and tissue repair and remodeling.

Macrophages originate from monocytes, which are a type of white blood cell produced in the bone marrow. When monocytes enter the tissues, they differentiate into macrophages, which have a larger size and more specialized functions than monocytes. Macrophages can change their shape and move through tissues to reach sites of infection or injury. They also produce cytokines, chemokines, and other signaling molecules that help coordinate the immune response and recruit other immune cells to the site of infection or injury.

Macrophages have a variety of surface receptors that allow them to recognize and respond to different types of foreign substances and signals from other cells. They can engulf and digest foreign particles, bacteria, and viruses through a process called phagocytosis. Macrophages also play a role in presenting antigens to T cells, which are another type of immune cell that helps coordinate the immune response.

Overall, macrophages are crucial for maintaining tissue homeostasis, defending against infection, and promoting wound healing and tissue repair. Dysregulation of macrophage function has been implicated in a variety of diseases, including cancer, autoimmune disorders, and chronic inflammatory conditions.

Natural Killer (NK) cells are a type of lymphocyte, which are large granular innate immune cells that play a crucial role in the host's defense against viral infections and malignant transformations. They do not require prior sensitization to target and destroy abnormal cells, such as virus-infected cells or tumor cells. NK cells recognize their targets through an array of germline-encoded activating and inhibitory receptors that detect the alterations in the cell surface molecules of potential targets. Upon activation, NK cells release cytotoxic granules containing perforins and granzymes to induce target cell apoptosis, and they also produce a variety of cytokines and chemokines to modulate immune responses. Overall, natural killer cells serve as a critical component of the innate immune system, providing rapid and effective responses against infected or malignant cells.

Apoptosis is a programmed and controlled cell death process that occurs in multicellular organisms. It is a natural process that helps maintain tissue homeostasis by eliminating damaged, infected, or unwanted cells. During apoptosis, the cell undergoes a series of morphological changes, including cell shrinkage, chromatin condensation, and fragmentation into membrane-bound vesicles called apoptotic bodies. These bodies are then recognized and engulfed by neighboring cells or phagocytic cells, preventing an inflammatory response. Apoptosis is regulated by a complex network of intracellular signaling pathways that involve proteins such as caspases, Bcl-2 family members, and inhibitors of apoptosis (IAPs).

Th2 cells, or T helper 2 cells, are a type of CD4+ T cell that plays a key role in the immune response to parasites and allergens. They produce cytokines such as IL-4, IL-5, IL-13 which promote the activation and proliferation of eosinophils, mast cells, and B cells, leading to the production of antibodies such as IgE. Th2 cells also play a role in the pathogenesis of allergic diseases such as asthma, atopic dermatitis, and allergic rhinitis.

It's important to note that an imbalance in Th1/Th2 response can lead to immune dysregulation and disease states. For example, an overactive Th2 response can lead to allergic reactions while an underactive Th2 response can lead to decreased ability to fight off parasitic infections.

It's also worth noting that there are other subsets of CD4+ T cells such as Th1, Th17, Treg and others, each with their own specific functions and cytokine production profiles.

Coagulants are substances that promote the process of coagulation or clotting. They are often used in medical settings to help control bleeding and promote healing. Coagulants work by encouraging the formation of a clot, which helps to stop the flow of blood from a wound or cut.

There are several different types of coagulants that may be used in medical treatments. Some coagulants are naturally occurring substances, such as vitamin K, which is essential for the production of certain clotting factors in the body. Other coagulants may be synthetic or semi-synthetic compounds, such as recombinant activated factor VII (rFVIIa), which is used to treat bleeding disorders and prevent excessive bleeding during surgery.

Coagulants are often administered through injection or infusion, but they can also be applied topically to wounds or cuts. In some cases, coagulants may be used in combination with other treatments, such as compression or cauterization, to help control bleeding and promote healing.

It is important to note that while coagulants can be helpful in controlling bleeding and promoting healing, they can also increase the risk of blood clots and other complications. As a result, they should only be used under the guidance and supervision of a qualified healthcare professional.

Inbred strains of mice are defined as lines of mice that have been brother-sister mated for at least 20 consecutive generations. This results in a high degree of homozygosity, where the mice of an inbred strain are genetically identical to one another, with the exception of spontaneous mutations.

Inbred strains of mice are widely used in biomedical research due to their genetic uniformity and stability, which makes them useful for studying the genetic basis of various traits, diseases, and biological processes. They also provide a consistent and reproducible experimental system, as compared to outbred or genetically heterogeneous populations.

Some commonly used inbred strains of mice include C57BL/6J, BALB/cByJ, DBA/2J, and 129SvEv. Each strain has its own unique genetic background and phenotypic characteristics, which can influence the results of experiments. Therefore, it is important to choose the appropriate inbred strain for a given research question.

Immunologic adjuvants are substances that are added to a vaccine to enhance the body's immune response to the antigens contained in the vaccine. They work by stimulating the immune system and promoting the production of antibodies and activating immune cells, such as T-cells and macrophages, which help to provide a stronger and more sustained immune response to the vaccine.

Immunologic adjuvants can be derived from various sources, including bacteria, viruses, and chemicals. Some common examples include aluminum salts (alum), oil-in-water emulsions (such as MF59), and bacterial components (such as lipopolysaccharide or LPS).

The use of immunologic adjuvants in vaccines can help to improve the efficacy of the vaccine, particularly for vaccines that contain weak or poorly immunogenic antigens. They can also help to reduce the amount of antigen needed in a vaccine, which can be beneficial for vaccines that are difficult or expensive to produce.

It's important to note that while adjuvants can enhance the immune response to a vaccine, they can also increase the risk of adverse reactions, such as inflammation and pain at the injection site. Therefore, the use of immunologic adjuvants must be carefully balanced against their potential benefits and risks.

1. Receptors: In the context of physiology and medicine, receptors are specialized proteins found on the surface of cells or inside cells that detect and respond to specific molecules, known as ligands. These interactions can trigger a range of responses within the cell, such as starting a signaling pathway or changing the cell's behavior. There are various types of receptors, including ion channels, G protein-coupled receptors, and enzyme-linked receptors.

2. Antigen: An antigen is any substance (usually a protein) that can be recognized by the immune system, specifically by antibodies or T-cells, as foreign and potentially harmful. Antigens can be derived from various sources, such as bacteria, viruses, fungi, parasites, or even non-living substances like pollen, chemicals, or toxins. An antigen typically contains epitopes, which are the specific regions that antibodies or T-cell receptors recognize and bind to.

3. T-Cell: Also known as T lymphocytes, T-cells are a type of white blood cell that plays a crucial role in cell-mediated immunity, a part of the adaptive immune system. They are produced in the bone marrow and mature in the thymus gland. There are several types of T-cells, including CD4+ helper T-cells, CD8+ cytotoxic T-cells, and regulatory T-cells (Tregs). T-cells recognize antigens presented to them by antigen-presenting cells (APCs) via their surface receptors called the T-cell receptor (TCR). Once activated, T-cells can proliferate and differentiate into various effector cells that help eliminate infected or damaged cells.

Salt tolerance, in a medical context, refers to the body's ability to maintain normal physiological functions despite high levels of salt (sodium chloride) in the system. While our kidneys usually regulate sodium levels, certain medical conditions such as some forms of kidney disease or heart failure can impair this process, leading to an accumulation of sodium in the body. Some individuals may have a genetic predisposition to better handle higher salt intakes, but generally, a high-salt diet is discouraged due to risks of hypertension and other health issues for most people.

Neoplasm antigens, also known as tumor antigens, are substances that are produced by cancer cells (neoplasms) and can stimulate an immune response. These antigens can be proteins, carbohydrates, or other molecules that are either unique to the cancer cells or are overexpressed or mutated versions of normal cellular proteins.

Neoplasm antigens can be classified into two main categories: tumor-specific antigens (TSAs) and tumor-associated antigens (TAAs). TSAs are unique to cancer cells and are not expressed by normal cells, while TAAs are present at low levels in normal cells but are overexpressed or altered in cancer cells.

TSAs can be further divided into viral antigens and mutated antigens. Viral antigens are produced when cancer is caused by a virus, such as human papillomavirus (HPV) in cervical cancer. Mutated antigens are the result of genetic mutations that occur during cancer development and are unique to each patient's tumor.

Neoplasm antigens play an important role in the immune response against cancer. They can be recognized by the immune system, leading to the activation of immune cells such as T cells and natural killer (NK) cells, which can then attack and destroy cancer cells. However, cancer cells often develop mechanisms to evade the immune response, allowing them to continue growing and spreading.

Understanding neoplasm antigens is important for the development of cancer immunotherapies, which aim to enhance the body's natural immune response against cancer. These therapies include checkpoint inhibitors, which block proteins that inhibit T cell activation, and therapeutic vaccines, which stimulate an immune response against specific tumor antigens.

Immunologic factors refer to the elements of the immune system that contribute to the body's defense against foreign substances, infectious agents, and cancerous cells. These factors include various types of white blood cells (such as lymphocytes, neutrophils, monocytes, and eosinophils), antibodies, complement proteins, cytokines, and other molecules involved in the immune response.

Immunologic factors can be categorized into two main types: innate immunity and adaptive immunity. Innate immunity is the non-specific defense mechanism that provides immediate protection against pathogens through physical barriers (e.g., skin, mucous membranes), chemical barriers (e.g., stomach acid, enzymes), and inflammatory responses. Adaptive immunity, on the other hand, is a specific defense mechanism that develops over time as the immune system learns to recognize and respond to particular pathogens or antigens.

Abnormalities in immunologic factors can lead to various medical conditions, such as autoimmune disorders, immunodeficiency diseases, and allergies. Therefore, understanding immunologic factors is crucial for diagnosing and treating these conditions.

Glycogen Storage Disease Type II, also known as Pompe Disease, is a genetic disorder caused by a deficiency of the enzyme acid alpha-glucosidase (GAA). This enzyme is responsible for breaking down glycogen, a complex sugar that serves as energy storage, within lysosomes. When GAA is deficient, glycogen accumulates in various tissues, particularly in muscle cells, leading to their dysfunction and damage.

The severity of Pompe Disease can vary significantly, depending on the amount of functional enzyme activity remaining. The classic infantile-onset form presents within the first few months of life with severe muscle weakness, hypotonia, feeding difficulties, and respiratory insufficiency. This form is often fatal by 1-2 years of age if left untreated.

A later-onset form, which can present in childhood, adolescence, or adulthood, has a more variable clinical course. Affected individuals may experience progressive muscle weakness, respiratory insufficiency, and cardiomyopathy, although the severity and rate of progression are generally less pronounced than in the infantile-onset form.

Enzyme replacement therapy with recombinant human GAA is available for the treatment of Pompe Disease and has been shown to improve survival and motor function in affected individuals.

A genetic vector is a vehicle, often a plasmid or a virus, that is used to introduce foreign DNA into a host cell as part of genetic engineering or gene therapy techniques. The vector contains the desired gene or genes, along with regulatory elements such as promoters and enhancers, which are needed for the expression of the gene in the target cells.

The choice of vector depends on several factors, including the size of the DNA to be inserted, the type of cell to be targeted, and the efficiency of uptake and expression required. Commonly used vectors include plasmids, adenoviruses, retroviruses, and lentiviruses.

Plasmids are small circular DNA molecules that can replicate independently in bacteria. They are often used as cloning vectors to amplify and manipulate DNA fragments. Adenoviruses are double-stranded DNA viruses that infect a wide range of host cells, including human cells. They are commonly used as gene therapy vectors because they can efficiently transfer genes into both dividing and non-dividing cells.

Retroviruses and lentiviruses are RNA viruses that integrate their genetic material into the host cell's genome. This allows for stable expression of the transgene over time. Lentiviruses, a subclass of retroviruses, have the advantage of being able to infect non-dividing cells, making them useful for gene therapy applications in post-mitotic tissues such as neurons and muscle cells.

Overall, genetic vectors play a crucial role in modern molecular biology and medicine, enabling researchers to study gene function, develop new therapies, and modify organisms for various purposes.

Lymphocyte depletion is a medical term that refers to the reduction in the number of lymphocytes (a type of white blood cell) in the body. Lymphocytes play a crucial role in the immune system, as they help to fight off infections and diseases.

Lymphocyte depletion can occur due to various reasons, including certain medical treatments such as chemotherapy or radiation therapy, immune disorders, viral infections, or bone marrow transplantation. This reduction in lymphocytes can make a person more susceptible to infections and diseases, as their immune system is weakened.

There are different types of lymphocytes, including T cells, B cells, and natural killer (NK) cells, and lymphocyte depletion can affect one or all of these types. In some cases, lymphocyte depletion may be temporary and resolve on its own or with treatment. However, in other cases, it may be more prolonged and require medical intervention to manage the associated risks and complications.

Maternal-fetal exchange, also known as maternal-fetal transport or placental transfer, refers to the physiological process by which various substances are exchanged between the mother and fetus through the placenta. This exchange includes the transfer of oxygen and nutrients from the mother's bloodstream to the fetal bloodstream, as well as the removal of waste products and carbon dioxide from the fetal bloodstream to the mother's bloodstream.

The process occurs via passive diffusion, facilitated diffusion, and active transport mechanisms across the placental barrier, which is composed of fetal capillary endothelial cells, the extracellular matrix, and the syncytiotrophoblast layer of the placenta. The maternal-fetal exchange is crucial for the growth, development, and survival of the fetus throughout pregnancy.

"CBA" is an abbreviation for a specific strain of inbred mice that were developed at the Cancer Research Institute in London. The "Inbred CBA" mice are genetically identical individuals within the same strain, due to many generations of brother-sister matings. This results in a homozygous population, making them valuable tools for research because they reduce variability and increase reproducibility in experimental outcomes.

The CBA strain is known for its susceptibility to certain diseases, such as autoimmune disorders and cancer, which makes it a popular choice for researchers studying those conditions. Additionally, the CBA strain has been widely used in studies related to transplantation immunology, infectious diseases, and genetic research.

It's important to note that while "Inbred CBA" mice are a well-established and useful tool in biomedical research, they represent only one of many inbred strains available for scientific investigation. Each strain has its own unique characteristics and advantages, depending on the specific research question being asked.

Extracorporeal photopheresis (ECP) is a medical treatment that involves the separation of peripheral blood mononuclear cells, which are then exposed to photoactivation. This process is repeated in multiple sessions and is used primarily in the management of cutaneous T-cell lymphoma (CTCL), as well as for the prevention of organ rejection in transplant patients. The exposure to photoactivation leads to the induction of apoptosis, or programmed cell death, in the affected cells, which can help to reduce inflammation and modulate the immune response. ECP is typically administered in an outpatient setting and has been shown to be a safe and effective treatment option for many patients with CTCL.

Cytotoxic T-lymphocytes, also known as CD8+ T cells, are a type of white blood cell that plays a central role in the cell-mediated immune system. They are responsible for identifying and destroying virus-infected cells and cancer cells. When a cytotoxic T-lymphocyte recognizes a specific antigen presented on the surface of an infected or malignant cell, it becomes activated and releases toxic substances such as perforins and granzymes, which can create pores in the target cell's membrane and induce apoptosis (programmed cell death). This process helps to eliminate the infected or malignant cells and prevent the spread of infection or cancer.

Immunophenotyping is a medical laboratory technique used to identify and classify cells, usually in the context of hematologic (blood) disorders and malignancies (cancers), based on their surface or intracellular expression of various proteins and antigens. This technique utilizes specific antibodies tagged with fluorochromes, which bind to the target antigens on the cell surface or within the cells. The labeled cells are then analyzed using flow cytometry, allowing for the detection and quantification of multiple antigenic markers simultaneously.

Immunophenotyping helps in understanding the distribution of different cell types, their subsets, and activation status, which can be crucial in diagnosing various hematological disorders, immunodeficiencies, and distinguishing between different types of leukemias, lymphomas, and other malignancies. Additionally, it can also be used to monitor the progression of diseases, evaluate the effectiveness of treatments, and detect minimal residual disease (MRD) during follow-up care.

Interleukin-2 (IL-2) is a type of cytokine, which are signaling molecules that mediate and regulate immunity, inflammation, and hematopoiesis. Specifically, IL-2 is a growth factor for T cells, a type of white blood cell that plays a central role in the immune response. It is primarily produced by CD4+ T cells (also known as T helper cells) and stimulates the proliferation and differentiation of activated T cells, including effector T cells and regulatory T cells. IL-2 also has roles in the activation and function of other immune cells, such as B cells, natural killer cells, and dendritic cells. Dysregulation of IL-2 production or signaling can contribute to various pathological conditions, including autoimmune diseases, chronic infections, and cancer.

A dose-response relationship in immunology refers to the quantitative relationship between the dose or amount of an antigen (a substance that triggers an immune response) and the magnitude or strength of the resulting immune response. Generally, as the dose of an antigen increases, the intensity and/or duration of the immune response also increase, up to a certain point. This relationship helps in determining the optimal dosage for vaccines and immunotherapies, ensuring sufficient immune activation while minimizing potential adverse effects.

CD4 antigens, also known as CD4 proteins or CD4 molecules, are a type of cell surface receptor found on certain immune cells, including T-helper cells and monocytes. They play a critical role in the immune response by binding to class II major histocompatibility complex (MHC) molecules on the surface of antigen-presenting cells and helping to activate T-cells. CD4 antigens are also the primary target of the human immunodeficiency virus (HIV), which causes AIDS, leading to the destruction of CD4-positive T-cells and a weakened immune system.

Alpha-glucosidases are a group of enzymes that break down complex carbohydrates into simpler sugars, such as glucose, by hydrolyzing the alpha-1,4 and alpha-1,6 glycosidic bonds in oligosaccharides, disaccharides, and polysaccharides. These enzymes are located on the brush border of the small intestine and play a crucial role in carbohydrate digestion and absorption.

Inhibitors of alpha-glucosidases, such as acarbose and miglitol, are used in the treatment of type 2 diabetes to slow down the digestion and absorption of carbohydrates, which helps to reduce postprandial glucose levels and improve glycemic control.

Immune complex diseases are medical conditions that occur when the immune system produces an abnormal response to certain antigens, leading to the formation and deposition of immune complexes in various tissues and organs. These immune complexes consist of antibodies bound to antigens, which can trigger an inflammatory reaction and damage the surrounding tissue.

Immune complex diseases can be classified into two categories: acute and chronic. Acute immune complex diseases include serum sickness and hypersensitivity vasculitis, while chronic immune complex diseases include systemic lupus erythematosus (SLE), rheumatoid arthritis, and membranoproliferative glomerulonephritis.

The symptoms of immune complex diseases depend on the location and extent of tissue damage. They can range from mild to severe and may include fever, joint pain, skin rashes, kidney dysfunction, and neurological problems. Treatment typically involves medications that suppress the immune system and reduce inflammation, such as corticosteroids, immunosuppressants, and anti-inflammatory drugs.

Physiological adaptation refers to the changes or modifications that occur in an organism's biological functions or structures as a result of environmental pressures or changes. These adaptations enable the organism to survive and reproduce more successfully in its environment. They can be short-term, such as the constriction of blood vessels in response to cold temperatures, or long-term, such as the evolution of longer limbs in animals that live in open environments.

In the context of human physiology, examples of physiological adaptation include:

1. Acclimatization: The process by which the body adjusts to changes in environmental conditions, such as altitude or temperature. For example, when a person moves to a high-altitude location, their body may produce more red blood cells to compensate for the lower oxygen levels, leading to improved oxygen delivery to tissues.

2. Exercise adaptation: Regular physical activity can lead to various physiological adaptations, such as increased muscle strength and endurance, enhanced cardiovascular function, and improved insulin sensitivity.

3. Hormonal adaptation: The body can adjust hormone levels in response to changes in the environment or internal conditions. For instance, during prolonged fasting, the body releases stress hormones like cortisol and adrenaline to help maintain energy levels and prevent muscle wasting.

4. Sensory adaptation: Our senses can adapt to different stimuli over time. For example, when we enter a dark room after being in bright sunlight, it takes some time for our eyes to adjust to the new light level. This process is known as dark adaptation.

5. Aging-related adaptations: As we age, various physiological changes occur that help us adapt to the changing environment and maintain homeostasis. These include changes in body composition, immune function, and cognitive abilities.

Lymphocytes are a type of white blood cell that is an essential part of the immune system. They are responsible for recognizing and responding to potentially harmful substances such as viruses, bacteria, and other foreign invaders. There are two main types of lymphocytes: B-lymphocytes (B-cells) and T-lymphocytes (T-cells).

B-lymphocytes produce antibodies, which are proteins that help to neutralize or destroy foreign substances. When a B-cell encounters a foreign substance, it becomes activated and begins to divide and differentiate into plasma cells, which produce and secrete large amounts of antibodies. These antibodies bind to the foreign substance, marking it for destruction by other immune cells.

T-lymphocytes, on the other hand, are involved in cell-mediated immunity. They directly attack and destroy infected cells or cancerous cells. T-cells can also help to regulate the immune response by producing chemical signals that activate or inhibit other immune cells.

Lymphocytes are produced in the bone marrow and mature in either the bone marrow (B-cells) or the thymus gland (T-cells). They circulate throughout the body in the blood and lymphatic system, where they can be found in high concentrations in lymph nodes, the spleen, and other lymphoid organs.

Abnormalities in the number or function of lymphocytes can lead to a variety of immune-related disorders, including immunodeficiency diseases, autoimmune disorders, and cancer.

Autoimmune encephalomyelitis (EAE) is a model of inflammatory demyelinating disease used in medical research to study the mechanisms of multiple sclerosis (MS) and develop new therapies. It is experimentally induced in laboratory animals, typically mice or rats, through immunization with myelin antigens or T-cell transfer. The resulting immune response leads to inflammation, demyelination, and neurological dysfunction in the central nervous system (CNS), mimicking certain aspects of MS.

EAE is a valuable tool for understanding the pathogenesis of MS and testing potential treatments. However, it is essential to recognize that EAE is an experimental model and may not fully recapitulate all features of human autoimmune encephalomyelitis.

Lipopolysaccharides (LPS) are large molecules found in the outer membrane of Gram-negative bacteria. They consist of a hydrophilic polysaccharide called the O-antigen, a core oligosaccharide, and a lipid portion known as Lipid A. The Lipid A component is responsible for the endotoxic activity of LPS, which can trigger a powerful immune response in animals, including humans. This response can lead to symptoms such as fever, inflammation, and septic shock, especially when large amounts of LPS are introduced into the bloodstream.

Hypersensitivity is an exaggerated or inappropriate immune response to a substance that is generally harmless to most people. It's also known as an allergic reaction. This abnormal response can be caused by various types of immunological mechanisms, including antibody-mediated reactions (types I, II, and III) and cell-mediated reactions (type IV). The severity of the hypersensitivity reaction can range from mild discomfort to life-threatening conditions. Common examples of hypersensitivity reactions include allergic rhinitis, asthma, atopic dermatitis, food allergies, and anaphylaxis.

H-2 antigens are a group of cell surface proteins found in mice that play a critical role in the immune system. They are similar to the human leukocyte antigen (HLA) complex in humans and are involved in the presentation of peptide antigens to T cells, which is a crucial step in the adaptive immune response.

The H-2 antigens are encoded by a cluster of genes located on chromosome 17 in mice. They are highly polymorphic, meaning that there are many different variations of these proteins circulating in the population. This genetic diversity allows for a wide range of potential peptide antigens to be presented to T cells, thereby enhancing the ability of the immune system to recognize and respond to a variety of pathogens.

The H-2 antigens are divided into two classes based on their function and structure. Class I H-2 antigens are found on almost all nucleated cells and consist of a heavy chain, a light chain, and a peptide fragment. They present endogenous peptides, such as those derived from viruses that infect the cell, to CD8+ T cells.

Class II H-2 antigens, on the other hand, are found primarily on professional antigen-presenting cells, such as dendritic cells and macrophages. They consist of an alpha chain and a beta chain and present exogenous peptides, such as those derived from bacteria that have been engulfed by the cell, to CD4+ T cells.

Overall, H-2 antigens are essential components of the mouse immune system, allowing for the recognition and elimination of pathogens and infected cells.

Genetic therapy, also known as gene therapy, is a medical intervention that involves the use of genetic material, such as DNA or RNA, to treat or prevent diseases. It works by introducing functional genes into cells to replace missing or faulty ones caused by genetic disorders or mutations. The introduced gene is incorporated into the recipient's genome, allowing for the production of a therapeutic protein that can help manage the disease symptoms or even cure the condition.

There are several approaches to genetic therapy, including:

1. Replacing a faulty gene with a healthy one
2. Inactivating or "silencing" a dysfunctional gene causing a disease
3. Introducing a new gene into the body to help fight off a disease, such as cancer

Genetic therapy holds great promise for treating various genetic disorders, including cystic fibrosis, muscular dystrophy, hemophilia, and certain types of cancer. However, it is still an evolving field with many challenges, such as efficient gene delivery, potential immune responses, and ensuring the safety and long-term effectiveness of the therapy.

Toll-like receptors (TLRs) are a type of pattern recognition receptors (PRRs) that play a crucial role in the innate immune system. They are transmembrane proteins located on the surface of various immune cells, including macrophages, dendritic cells, and B cells. TLRs recognize specific patterns of molecules called pathogen-associated molecular patterns (PAMPs) that are found on microbes such as bacteria, viruses, fungi, and parasites.

Once TLRs bind to PAMPs, they initiate a signaling cascade that activates the immune response, leading to the production of cytokines and chemokines, which in turn recruit and activate other immune cells. TLRs also play a role in the adaptive immune response by activating antigen-presenting cells and promoting the differentiation of T cells.

There are ten known human TLRs, each with distinct ligand specificity and cellular localization. TLRs can be found on the cell surface or within endosomes, where they recognize different types of PAMPs. For example, TLR4 recognizes lipopolysaccharides (LPS) found on gram-negative bacteria, while TLR3 recognizes double-stranded RNA from viruses.

Overall, TLRs are critical components of the immune system's ability to detect and respond to infections, and dysregulation of TLR signaling has been implicated in various inflammatory diseases and cancers.

"Intraperitoneal injection" is a medical term that refers to the administration of a substance or medication directly into the peritoneal cavity, which is the space between the lining of the abdominal wall and the organs contained within it. This type of injection is typically used in clinical settings for various purposes, such as delivering chemotherapy drugs, anesthetics, or other medications directly to the abdominal organs.

The procedure involves inserting a needle through the abdominal wall and into the peritoneal cavity, taking care to avoid any vital structures such as blood vessels or nerves. Once the needle is properly positioned, the medication can be injected slowly and carefully to ensure even distribution throughout the cavity.

It's important to note that intraperitoneal injections are typically reserved for situations where other routes of administration are not feasible or effective, as they carry a higher risk of complications such as infection, bleeding, or injury to surrounding organs. As with any medical procedure, it should only be performed by trained healthcare professionals under appropriate clinical circumstances.

A Lymphocyte Culture Test, Mixed (LCTM) is not a standardized medical test with a universally accepted definition. However, in some contexts, it may refer to a laboratory procedure where both T-lymphocytes and B-lymphocytes are cultured together from a sample of peripheral blood or other tissues. This test is sometimes used in research or specialized diagnostic settings to evaluate the immune function or to study the interactions between T-cells and B-cells in response to various stimuli, such as antigens or mitogens.

The test typically involves isolating lymphocytes from a sample, adding them to a culture medium along with appropriate stimulants, and then incubating the mixture for a period of time. The resulting responses, such as proliferation, differentiation, or production of cytokines, can be measured and analyzed to gain insights into the immune function or dysfunction.

It's important to note that LCTM is not a routine diagnostic test and its use and interpretation may vary depending on the specific laboratory or research setting.

An autograft, also known as an autologous graft, is a type of graft in which tissue is transferred from one part of the body to another in the same individual. In other words, the tissue is taken from the patient themselves and then transplanted to a different site on their own body. This can be done for a variety of reasons, such as to repair damaged or missing tissue due to injury, disease, or surgery.

There are several types of autografts, including:

* Skin grafts: In this type of autograft, healthy skin is taken from one part of the body and transplanted to another part of the body that has been damaged or lost its own skin due to burns, injury, or surgery.
* Bone grafts: In this type of autograft, bone tissue is taken from one part of the body and transplanted to another part of the body to repair a fracture or fusion, or to provide support for dental implants.
* Tendon grafts: In this type of autograft, tendons are taken from one part of the body and transplanted to another part of the body to replace damaged or torn tendons.
* Cartilage grafts: In this type of autograft, cartilage tissue is taken from one part of the body and transplanted to another part of the body to repair damaged or missing cartilage due to injury or disease.

Autografts are generally considered to be the "gold standard" for grafting procedures because they have a lower risk of rejection compared to allografts (grafts from another individual) and xenografts (grafts from an animal). However, there are some risks associated with autografts, including infection, bleeding, and pain at the donor site.

Neoplasms are abnormal growths of cells or tissues in the body that serve no physiological function. They can be benign (non-cancerous) or malignant (cancerous). Benign neoplasms are typically slow growing and do not spread to other parts of the body, while malignant neoplasms are aggressive, invasive, and can metastasize to distant sites.

Neoplasms occur when there is a dysregulation in the normal process of cell division and differentiation, leading to uncontrolled growth and accumulation of cells. This can result from genetic mutations or other factors such as viral infections, environmental exposures, or hormonal imbalances.

Neoplasms can develop in any organ or tissue of the body and can cause various symptoms depending on their size, location, and type. Treatment options for neoplasms include surgery, radiation therapy, chemotherapy, immunotherapy, and targeted therapy, among others.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

Exercise tolerance is a term used to describe the ability of an individual to perform physical activity or exercise without experiencing symptoms such as shortness of breath, chest pain, or undue fatigue. It is often used as a measure of cardiovascular fitness and can be assessed through various tests, such as a stress test or a six-minute walk test. Exercise intolerance may indicate the presence of underlying medical conditions, such as heart disease, lung disease, or deconditioning.

CD80 (also known as B7-1) is a cell surface protein that functions as a costimulatory molecule in the immune system. It is primarily expressed on antigen presenting cells such as dendritic cells, macrophages, and B cells. CD80 binds to the CD28 receptor on T cells, providing a critical second signal necessary for T cell activation and proliferation. This interaction plays a crucial role in the initiation of an effective immune response against pathogens and tumors.

CD80 can also interact with another receptor called CTLA-4 (cytotoxic T lymphocyte antigen 4), which is expressed on activated T cells. The binding of CD80 to CTLA-4 delivers a negative signal that helps regulate the immune response and prevent overactivation, contributing to the maintenance of self-tolerance and preventing autoimmunity.

In summary, CD80 is an important antigen involved in the regulation of the adaptive immune response by modulating T cell activation and proliferation through its interactions with CD28 and CTLA-4 receptors.

Vaccination is a simple, safe, and effective way to protect people against harmful diseases, before they come into contact with them. It uses your body's natural defenses to build protection to specific infections and makes your immune system stronger.

A vaccination usually contains a small, harmless piece of a virus or bacteria (or toxins produced by these germs) that has been made inactive or weakened so it won't cause the disease itself. This piece of the germ is known as an antigen. When the vaccine is introduced into the body, the immune system recognizes the antigen as foreign and produces antibodies to fight it.

If a person then comes into contact with the actual disease-causing germ, their immune system will recognize it and immediately produce antibodies to destroy it. The person is therefore protected against that disease. This is known as active immunity.

Vaccinations are important for both individual and public health. They prevent the spread of contagious diseases and protect vulnerable members of the population, such as young children, the elderly, and people with weakened immune systems who cannot be vaccinated or for whom vaccination is not effective.

Blood glucose, also known as blood sugar, is the concentration of glucose in the blood. Glucose is a simple sugar that serves as the main source of energy for the body's cells. It is carried to each cell through the bloodstream and is absorbed into the cells with the help of insulin, a hormone produced by the pancreas.

The normal range for blood glucose levels in humans is typically between 70 and 130 milligrams per deciliter (mg/dL) when fasting, and less than 180 mg/dL after meals. Levels that are consistently higher than this may indicate diabetes or other metabolic disorders.

Blood glucose levels can be measured through a variety of methods, including fingerstick blood tests, continuous glucose monitoring systems, and laboratory tests. Regular monitoring of blood glucose levels is important for people with diabetes to help manage their condition and prevent complications.

Recombinant proteins are artificially created proteins produced through the use of recombinant DNA technology. This process involves combining DNA molecules from different sources to create a new set of genes that encode for a specific protein. The resulting recombinant protein can then be expressed, purified, and used for various applications in research, medicine, and industry.

Recombinant proteins are widely used in biomedical research to study protein function, structure, and interactions. They are also used in the development of diagnostic tests, vaccines, and therapeutic drugs. For example, recombinant insulin is a common treatment for diabetes, while recombinant human growth hormone is used to treat growth disorders.

The production of recombinant proteins typically involves the use of host cells, such as bacteria, yeast, or mammalian cells, which are engineered to express the desired protein. The host cells are transformed with a plasmid vector containing the gene of interest, along with regulatory elements that control its expression. Once the host cells are cultured and the protein is expressed, it can be purified using various chromatography techniques.

Overall, recombinant proteins have revolutionized many areas of biology and medicine, enabling researchers to study and manipulate proteins in ways that were previously impossible.

Systemic Lupus Erythematosus (SLE) is a complex autoimmune disease that can affect almost any organ or system in the body. In SLE, the immune system produces an exaggerated response, leading to the production of autoantibodies that attack the body's own cells and tissues, causing inflammation and damage. The symptoms and severity of SLE can vary widely from person to person, but common features include fatigue, joint pain, skin rashes (particularly a "butterfly" rash across the nose and cheeks), fever, hair loss, and sensitivity to sunlight.

Systemic lupus erythematosus can also affect the kidneys, heart, lungs, brain, blood vessels, and other organs, leading to a wide range of symptoms such as kidney dysfunction, chest pain, shortness of breath, seizures, and anemia. The exact cause of SLE is not fully understood, but it is believed to involve a combination of genetic, environmental, and hormonal factors. Treatment typically involves medications to suppress the immune system and manage symptoms, and may require long-term management by a team of healthcare professionals.

An epitope is a specific region on an antigen (a substance that triggers an immune response) that is recognized and bound by an antibody or a T-cell receptor. In the case of T-lymphocytes, which are a type of white blood cell that plays a central role in cell-mediated immunity, epitopes are typically presented on the surface of infected cells in association with major histocompatibility complex (MHC) molecules.

T-lymphocytes recognize and respond to epitopes through their T-cell receptors (TCRs), which are membrane-bound proteins that can bind to specific epitopes presented on the surface of infected cells. There are two main types of T-lymphocytes: CD4+ T-cells, also known as helper T-cells, and CD8+ T-cells, also known as cytotoxic T-cells.

CD4+ T-cells recognize epitopes presented in the context of MHC class II molecules, which are typically expressed on the surface of professional antigen-presenting cells such as dendritic cells, macrophages, and B-cells. CD4+ T-cells help to coordinate the immune response by producing cytokines that activate other immune cells.

CD8+ T-cells recognize epitopes presented in the context of MHC class I molecules, which are expressed on the surface of almost all nucleated cells. CD8+ T-cells are able to directly kill infected cells by releasing cytotoxic granules that contain enzymes that can induce apoptosis (programmed cell death) in the target cell.

In summary, epitopes are specific regions on antigens that are recognized and bound by T-lymphocytes through their T-cell receptors. CD4+ T-cells recognize epitopes presented in the context of MHC class II molecules, while CD8+ T-cells recognize epitopes presented in the context of MHC class I molecules.

Blocking antibodies are a type of antibody that binds to a specific antigen but does not cause the immune system to directly attack the antigen. Instead, blocking antibodies prevent the antigen from interacting with other molecules or receptors, effectively "blocking" its activity. This can be useful in therapeutic settings, where blocking antibodies can be used to inhibit the activity of harmful proteins or toxins.

For example, some blocking antibodies have been developed to target and block the activity of specific cytokines, which are signaling molecules involved in inflammation and immune responses. By blocking the interaction between the cytokine and its receptor, these antibodies can help to reduce inflammation and alleviate symptoms in certain autoimmune diseases or chronic inflammatory conditions.

It's important to note that while blocking antibodies can be useful for therapeutic purposes, they can also have unintended consequences if they block the activity of essential proteins or molecules. Therefore, careful consideration and testing are required before using blocking antibodies as a treatment.

Islets of Langerhans transplantation is a surgical procedure that involves the transplantation of isolated islets from a deceased donor's pancreas into another person with type 1 diabetes. The islets of Langerhans are clusters of cells within the pancreas that produce hormones, including insulin, which regulates blood sugar levels.

In type 1 diabetes, the body's immune system mistakenly attacks and destroys these insulin-producing cells, leading to high blood sugar levels. Islet transplantation aims to replace the damaged islets with healthy ones from a donor, allowing the recipient's body to produce and regulate its own insulin again.

The procedure involves extracting the islets from the donor pancreas and infusing them into the recipient's liver through a small incision in the abdomen. Once inside the liver, the islets can sense glucose levels in the bloodstream and release insulin as needed to maintain normal blood sugar levels.

Islet transplantation has shown promising results in improving blood sugar control and reducing the risk of severe hypoglycemia (low blood sugar) in people with type 1 diabetes. However, it requires long-term immunosuppressive therapy to prevent rejection of the transplanted islets, which can have side effects and increase the risk of infections.

'DBA' is an abbreviation for 'Database of Genotypes and Phenotypes,' but in the context of "Inbred DBA mice," it refers to a specific strain of laboratory mice that have been inbred for many generations. The DBA strain is one of the oldest inbred strains, and it was established in 1909 by C.C. Little at the Bussey Institute of Harvard University.

The "Inbred DBA" mice are genetically identical mice that have been produced by brother-sister matings for more than 20 generations. This extensive inbreeding results in a homozygous population, where all members of the strain have the same genetic makeup. The DBA strain is further divided into several sub-strains, including DBA/1, DBA/2, and DBA/J, among others.

DBA mice are known for their black coat color, which can fade to gray with age, and they exhibit a range of phenotypic traits that make them useful for research purposes. For example, DBA mice have a high incidence of retinal degeneration, making them a valuable model for studying eye diseases. They also show differences in behavior, immune response, and susceptibility to various diseases compared to other inbred strains.

In summary, "Inbred DBA" mice are a specific strain of laboratory mice that have been inbred for many generations, resulting in a genetically identical population with distinct phenotypic traits. They are widely used in biomedical research to study various diseases and biological processes.

"Drought" is not a medical term. It is a term used in meteorology and environmental science to refer to a prolonged period of abnormally low rainfall, leading to water shortage and scarcity in the affected areas. Droughts can have various impacts on human health, including dehydration, heat-related illnesses, reduced air quality, increased transmission of waterborne diseases, and mental health issues related to stress and displacement. However, drought itself is not a medical condition.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

T-lymphocytes, also known as T-cells, are a type of white blood cell that plays a key role in the immune response. They help to protect the body from infection and disease by identifying and attacking foreign substances such as viruses and bacteria.

Helper-inducer T-lymphocytes, also known as CD4+ T-cells or Th0 cells, are a specific subset of T-lymphocytes that help to coordinate the immune response. They do this by activating other immune cells, such as B-lymphocytes (which produce antibodies) and cytotoxic T-lymphocytes (which directly attack infected cells). Helper-inducer T-lymphocytes also release cytokines, which are signaling molecules that help to regulate the immune response.

Helper-inducer T-lymphocytes can differentiate into different subsets of T-cells, depending on the type of cytokines they are exposed to. For example, they can differentiate into Th1 cells, which produce cytokines that help to activate cytotoxic T-lymphocytes and macrophages; or Th2 cells, which produce cytokines that help to activate B-lymphocytes and eosinophils.

It is important to note that helper-inducer T-lymphocytes play a crucial role in the immune response, and dysfunction of these cells can lead to immunodeficiency or autoimmune disorders.

Myeloid cells are a type of immune cell that originate from the bone marrow. They develop from hematopoietic stem cells, which can differentiate into various types of blood cells. Myeloid cells include monocytes, macrophages, granulocytes (such as neutrophils, eosinophils, and basophils), dendritic cells, and mast cells. These cells play important roles in the immune system, such as defending against pathogens, modulating inflammation, and participating in tissue repair and remodeling.

Myeloid cell development is a tightly regulated process that involves several stages of differentiation, including the commitment to the myeloid lineage, proliferation, and maturation into specific subtypes. Dysregulation of myeloid cell development or function can contribute to various diseases, such as infections, cancer, and autoimmune disorders.

A phenotype is the physical or biochemical expression of an organism's genes, or the observable traits and characteristics resulting from the interaction of its genetic constitution (genotype) with environmental factors. These characteristics can include appearance, development, behavior, and resistance to disease, among others. Phenotypes can vary widely, even among individuals with identical genotypes, due to differences in environmental influences, gene expression, and genetic interactions.

Up-regulation is a term used in molecular biology and medicine to describe an increase in the expression or activity of a gene, protein, or receptor in response to a stimulus. This can occur through various mechanisms such as increased transcription, translation, or reduced degradation of the molecule. Up-regulation can have important functional consequences, for example, enhancing the sensitivity or response of a cell to a hormone, neurotransmitter, or drug. It is a normal physiological process that can also be induced by disease or pharmacological interventions.

Oral administration is a route of giving medications or other substances by mouth. This can be in the form of tablets, capsules, liquids, pastes, or other forms that can be swallowed. Once ingested, the substance is absorbed through the gastrointestinal tract and enters the bloodstream to reach its intended target site in the body. Oral administration is a common and convenient route of medication delivery, but it may not be appropriate for all substances or in certain situations, such as when rapid onset of action is required or when the patient has difficulty swallowing.

CD40 ligand (CD40L or CD154) is a type II transmembrane protein and a member of the tumor necrosis factor (TNF) superfamily. It is primarily expressed on activated CD4+ T cells, but can also be found on other immune cells such as activated B cells, macrophages, and dendritic cells.

CD40 ligand binds to its receptor, CD40, which is mainly expressed on the surface of antigen-presenting cells (APCs) such as B cells, dendritic cells, and macrophages. The interaction between CD40L and CD40 plays a crucial role in the activation and regulation of the immune response.

CD40L-CD40 signaling is essential for T cell-dependent B cell activation, antibody production, and class switching. It also contributes to the activation and maturation of dendritic cells, promoting their ability to stimulate T cell responses. Dysregulation of CD40L-CD40 signaling has been implicated in various autoimmune diseases, transplant rejection, and cancer.

I'm happy to help! "Rats, Inbred Lew" is a specific strain of laboratory rats that have been inbred for research purposes. The "Lew" part of the name refers to the location where they were first developed, the Lewis Institute in Lake Bluff, Illinois, USA.

Inbreeding is a process of mating closely related individuals over many generations to create a genetically homogeneous population. This results in a high degree of genetic similarity among members of the strain, making them ideal for use as experimental models because any differences observed between individuals are more likely to be due to the experimental manipulation rather than genetic variation.

Inbred Lew rats have been widely used in biomedical research, particularly in studies related to hypertension and cardiovascular disease. They exhibit a number of unique characteristics that make them useful for these types of studies, including their susceptibility to developing high blood pressure when fed a high-salt diet or given certain drugs.

It's important to note that while inbred strains like Lew rats can be very useful tools for researchers, they are not perfect models for human disease. Because they have been bred in a controlled environment and selected for specific traits, they may not respond to experimental manipulations in the same way that humans or other animals would. Therefore, it's important to interpret findings from these studies with caution and consider multiple lines of evidence before drawing any firm conclusions.

Interleukin-4 (IL-4) is a type of cytokine, which is a cell signaling molecule that mediates communication between cells in the immune system. Specifically, IL-4 is produced by activated T cells and mast cells, among other cells, and plays an important role in the differentiation and activation of immune cells called Th2 cells.

Th2 cells are involved in the immune response to parasites, as well as in allergic reactions. IL-4 also promotes the growth and survival of B cells, which produce antibodies, and helps to regulate the production of certain types of antibodies. In addition, IL-4 has anti-inflammatory effects and can help to downregulate the immune response in some contexts.

Defects in IL-4 signaling have been implicated in a number of diseases, including asthma, allergies, and certain types of cancer.

CD3 antigens are a group of proteins found on the surface of T-cells, which are a type of white blood cell that plays a central role in the immune response. The CD3 antigens are composed of several different subunits (ε, δ, γ, and α) that associate to form the CD3 complex, which is involved in T-cell activation and signal transduction.

The CD3 complex is associated with the T-cell receptor (TCR), which recognizes and binds to specific antigens presented by antigen-presenting cells. When the TCR binds to an antigen, it triggers a series of intracellular signaling events that lead to T-cell activation and the initiation of an immune response.

CD3 antigens are important targets for immunotherapy in some diseases, such as certain types of cancer. For example, monoclonal antibodies that target CD3 have been developed to activate T-cells and enhance their ability to recognize and destroy tumor cells. However, CD3-targeted therapies can also cause side effects, such as cytokine release syndrome, which can be serious or life-threatening in some cases.

Immunologic memory, also known as adaptive immunity, refers to the ability of the immune system to recognize and mount a more rapid and effective response upon subsequent exposure to a pathogen or antigen that it has encountered before. This is a key feature of the vertebrate immune system and allows for long-term protection against infectious diseases.

Immunologic memory is mediated by specialized cells called memory T cells and B cells, which are produced during the initial response to an infection or immunization. These cells persist in the body after the pathogen has been cleared and can quickly respond to future encounters with the same or similar antigens. This rapid response leads to a more effective and efficient elimination of the pathogen, resulting in fewer symptoms and reduced severity of disease.

Immunologic memory is the basis for vaccines, which work by exposing the immune system to a harmless form of a pathogen or its components, inducing an initial response and generating memory cells that provide long-term protection against future infections.

The liver is a large, solid organ located in the upper right portion of the abdomen, beneath the diaphragm and above the stomach. It plays a vital role in several bodily functions, including:

1. Metabolism: The liver helps to metabolize carbohydrates, fats, and proteins from the food we eat into energy and nutrients that our bodies can use.
2. Detoxification: The liver detoxifies harmful substances in the body by breaking them down into less toxic forms or excreting them through bile.
3. Synthesis: The liver synthesizes important proteins, such as albumin and clotting factors, that are necessary for proper bodily function.
4. Storage: The liver stores glucose, vitamins, and minerals that can be released when the body needs them.
5. Bile production: The liver produces bile, a digestive juice that helps to break down fats in the small intestine.
6. Immune function: The liver plays a role in the immune system by filtering out bacteria and other harmful substances from the blood.

Overall, the liver is an essential organ that plays a critical role in maintaining overall health and well-being.

Peripheral tolerance, in the context of immunology and medicine, refers to a state of immune system unresponsiveness or non-reactivity to certain antigens (substances that can trigger an immune response) that are encountered outside the central lymphoid organs (thymus and bone marrow). This is a crucial mechanism to prevent the immune system from attacking the body's own cells and tissues, as well as harmless environmental antigens.

Peripheral tolerance is established and maintained through several mechanisms:

1. **Anergy:** T cells (a type of immune cell) that recognize self-antigens can become inactivated or anergic, meaning they cannot respond to those antigens anymore.
2. **Regulatory T cells (Tregs):** These are a special class of T cells that suppress the activation and proliferation of other immune cells. They play a critical role in maintaining peripheral tolerance by preventing autoimmune responses.
3. **Deletion:** Immature T and B cells that recognize self-antigens with high affinity can be eliminated in the periphery, thus preventing them from mounting an immune response against the body's own tissues.
4. **Immune ignorance:** Some self-antigens may not be encountered by the immune system due to their location or limited availability, leading to a state of ignorance and non-reactivity.

Defects in peripheral tolerance can lead to autoimmune diseases, where the immune system attacks the body's own cells and tissues.

Transforming Growth Factor-beta (TGF-β) is a type of cytokine, which is a cell signaling protein involved in the regulation of various cellular processes, including cell growth, differentiation, and apoptosis (programmed cell death). TGF-β plays a critical role in embryonic development, tissue homeostasis, and wound healing. It also has been implicated in several pathological conditions such as fibrosis, cancer, and autoimmune diseases.

TGF-β exists in multiple isoforms (TGF-β1, TGF-β2, and TGF-β3) that are produced by many different cell types, including immune cells, epithelial cells, and fibroblasts. The protein is synthesized as a precursor molecule, which is cleaved to release the active TGF-β peptide. Once activated, TGF-β binds to its receptors on the cell surface, leading to the activation of intracellular signaling pathways that regulate gene expression and cell behavior.

In summary, Transforming Growth Factor-beta (TGF-β) is a multifunctional cytokine involved in various cellular processes, including cell growth, differentiation, apoptosis, embryonic development, tissue homeostasis, and wound healing. It has been implicated in several pathological conditions such as fibrosis, cancer, and autoimmune diseases.

A dependovirus, also known as a dependent adenovirus or satellite adenovirus, is a type of virus that requires the presence of another virus, specifically an adenovirus, to replicate. Dependoviruses are small, non-enveloped viruses with a double-stranded DNA genome. They cannot complete their replication cycle without the help of an adenovirus, which provides necessary functions for the dependovirus to replicate.

Dependoviruses are clinically significant because they can cause disease in humans, particularly in individuals with weakened immune systems. In some cases, dependoviruses may also affect the severity and outcome of adenovirus infections. However, it is important to note that not all adenovirus infections are associated with dependovirus co-infections.

An allergen is a substance that can cause an allergic reaction in some people. These substances are typically harmless to most people, but for those with allergies, the immune system mistakenly identifies them as threats and overreacts, leading to the release of histamines and other chemicals that cause symptoms such as itching, sneezing, runny nose, rashes, hives, and difficulty breathing. Common allergens include pollen, dust mites, mold spores, pet dander, insect venom, and certain foods or medications. When a person comes into contact with an allergen, they may experience symptoms that range from mild to severe, depending on the individual's sensitivity to the substance and the amount of exposure.

Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.

Physiological stress is a response of the body to a demand or threat that disrupts homeostasis and activates the autonomic nervous system and hypothalamic-pituitary-adrenal (HPA) axis. This results in the release of stress hormones such as adrenaline, cortisol, and noradrenaline, which prepare the body for a "fight or flight" response. Increased heart rate, rapid breathing, heightened sensory perception, and increased alertness are some of the physiological changes that occur during this response. Chronic stress can have negative effects on various bodily functions, including the immune, cardiovascular, and nervous systems.

Lymphoid tissue is a specialized type of connective tissue that is involved in the immune function of the body. It is composed of lymphocytes (a type of white blood cell), which are responsible for producing antibodies and destroying infected or cancerous cells. Lymphoid tissue can be found throughout the body, but it is particularly concentrated in certain areas such as the lymph nodes, spleen, tonsils, and Peyer's patches in the small intestine.

Lymphoid tissue provides a site for the activation, proliferation, and differentiation of lymphocytes, which are critical components of the adaptive immune response. It also serves as a filter for foreign particles, such as bacteria and viruses, that may enter the body through various routes. The lymphatic system, which includes lymphoid tissue, helps to maintain the health and integrity of the body by protecting it from infection and disease.

The decidua is a specialized type of tissue that lines the uterus during pregnancy. It forms after the implantation of a fertilized egg (embryo) into the uterine lining, and it plays an important role in supporting the growth and development of the embryo and fetus.

The decidua is composed of several layers, including the decidual capsularis, which surrounds the embryo, and the decidual parietalis, which lines the rest of the uterus. The tissue is rich in blood vessels and contains a variety of immune cells that help to protect the developing fetus from infection.

During pregnancy, the decidua produces various hormones and growth factors that support the growth of the placenta, which provides nutrients and oxygen to the fetus. After the birth of the baby, the decidua is shed along with the placenta in a process called childbirth or parturition.

It's worth noting that abnormalities in the decidua can contribute to pregnancy complications such as preeclampsia, preterm labor, and miscarriage.

The intestinal mucosa is the innermost layer of the intestines, which comes into direct contact with digested food and microbes. It is a specialized epithelial tissue that plays crucial roles in nutrient absorption, barrier function, and immune defense. The intestinal mucosa is composed of several cell types, including absorptive enterocytes, mucus-secreting goblet cells, hormone-producing enteroendocrine cells, and immune cells such as lymphocytes and macrophages.

The surface of the intestinal mucosa is covered by a single layer of epithelial cells, which are joined together by tight junctions to form a protective barrier against harmful substances and microorganisms. This barrier also allows for the selective absorption of nutrients into the bloodstream. The intestinal mucosa also contains numerous lymphoid follicles, known as Peyer's patches, which are involved in immune surveillance and defense against pathogens.

In addition to its role in absorption and immunity, the intestinal mucosa is also capable of producing hormones that regulate digestion and metabolism. Dysfunction of the intestinal mucosa can lead to various gastrointestinal disorders, such as inflammatory bowel disease, celiac disease, and food allergies.

Membrane glycoproteins are proteins that contain oligosaccharide chains (glycans) covalently attached to their polypeptide backbone. They are integral components of biological membranes, spanning the lipid bilayer and playing crucial roles in various cellular processes.

The glycosylation of these proteins occurs in the endoplasmic reticulum (ER) and Golgi apparatus during protein folding and trafficking. The attached glycans can vary in structure, length, and composition, which contributes to the diversity of membrane glycoproteins.

Membrane glycoproteins can be classified into two main types based on their orientation within the lipid bilayer:

1. Type I (N-linked): These glycoproteins have a single transmembrane domain and an extracellular N-terminus, where the oligosaccharides are predominantly attached via asparagine residues (Asn-X-Ser/Thr sequon).
2. Type II (C-linked): These glycoproteins possess two transmembrane domains and an intracellular C-terminus, with the oligosaccharides linked to tryptophan residues via a mannose moiety.

Membrane glycoproteins are involved in various cellular functions, such as:

* Cell adhesion and recognition
* Receptor-mediated signal transduction
* Enzymatic catalysis
* Transport of molecules across membranes
* Cell-cell communication
* Immunological responses

Some examples of membrane glycoproteins include cell surface receptors (e.g., growth factor receptors, cytokine receptors), adhesion molecules (e.g., integrins, cadherins), and transporters (e.g., ion channels, ABC transporters).

Interleukin-17 (IL-17) is a type of cytokine, which are proteins that play a crucial role in cell signaling and communication during the immune response. IL-17 is primarily produced by a subset of T helper cells called Th17 cells, although other cell types like neutrophils, mast cells, natural killer cells, and innate lymphoid cells can also produce it.

IL-17 has several functions in the immune system, including:

1. Promoting inflammation: IL-17 stimulates the production of various proinflammatory cytokines, chemokines, and enzymes from different cell types, leading to the recruitment of immune cells like neutrophils to the site of infection or injury.
2. Defending against extracellular pathogens: IL-17 plays a critical role in protecting the body against bacterial and fungal infections by enhancing the recruitment and activation of neutrophils, which can engulf and destroy these microorganisms.
3. Regulating tissue homeostasis: IL-17 helps maintain the balance between immune tolerance and immunity in various tissues by regulating the survival, proliferation, and differentiation of epithelial cells, fibroblasts, and other structural components.

However, dysregulated IL-17 production or signaling has been implicated in several inflammatory and autoimmune diseases, such as psoriasis, rheumatoid arthritis, multiple sclerosis, and inflammatory bowel disease. Therefore, targeting the IL-17 pathway with specific therapeutics has emerged as a promising strategy for treating these conditions.

Coculture techniques refer to a type of experimental setup in which two or more different types of cells or organisms are grown and studied together in a shared culture medium. This method allows researchers to examine the interactions between different cell types or species under controlled conditions, and to study how these interactions may influence various biological processes such as growth, gene expression, metabolism, and signal transduction.

Coculture techniques can be used to investigate a wide range of biological phenomena, including the effects of host-microbe interactions on human health and disease, the impact of different cell types on tissue development and homeostasis, and the role of microbial communities in shaping ecosystems. These techniques can also be used to test the efficacy and safety of new drugs or therapies by examining their effects on cells grown in coculture with other relevant cell types.

There are several different ways to establish cocultures, depending on the specific research question and experimental goals. Some common methods include:

1. Mixed cultures: In this approach, two or more cell types are simply mixed together in a culture dish or flask and allowed to grow and interact freely.
2. Cell-layer cultures: Here, one cell type is grown on a porous membrane or other support structure, while the second cell type is grown on top of it, forming a layered coculture.
3. Conditioned media cultures: In this case, one cell type is grown to confluence and its culture medium is collected and then used to grow a second cell type. This allows the second cell type to be exposed to any factors secreted by the first cell type into the medium.
4. Microfluidic cocultures: These involve growing cells in microfabricated channels or chambers, which allow for precise control over the spatial arrangement and flow of nutrients, waste products, and signaling molecules between different cell types.

Overall, coculture techniques provide a powerful tool for studying complex biological systems and gaining insights into the mechanisms that underlie various physiological and pathological processes.

Cell separation is a process used to separate and isolate specific cell types from a heterogeneous mixture of cells. This can be accomplished through various physical or biological methods, depending on the characteristics of the cells of interest. Some common techniques for cell separation include:

1. Density gradient centrifugation: In this method, a sample containing a mixture of cells is layered onto a density gradient medium and then centrifuged. The cells are separated based on their size, density, and sedimentation rate, with denser cells settling closer to the bottom of the tube and less dense cells remaining near the top.

2. Magnetic-activated cell sorting (MACS): This technique uses magnetic beads coated with antibodies that bind to specific cell surface markers. The labeled cells are then passed through a column placed in a magnetic field, which retains the magnetically labeled cells while allowing unlabeled cells to flow through.

3. Fluorescence-activated cell sorting (FACS): In this method, cells are stained with fluorochrome-conjugated antibodies that recognize specific cell surface or intracellular markers. The stained cells are then passed through a laser beam, which excites the fluorophores and allows for the detection and sorting of individual cells based on their fluorescence profile.

4. Filtration: This simple method relies on the physical size differences between cells to separate them. Cells can be passed through filters with pore sizes that allow smaller cells to pass through while retaining larger cells.

5. Enzymatic digestion: In some cases, cells can be separated by enzymatically dissociating tissues into single-cell suspensions and then using various separation techniques to isolate specific cell types.

These methods are widely used in research and clinical settings for applications such as isolating immune cells, stem cells, or tumor cells from biological samples.

Homeostasis is a fundamental concept in the field of medicine and physiology, referring to the body's ability to maintain a stable internal environment, despite changes in external conditions. It is the process by which biological systems regulate their internal environment to remain in a state of dynamic equilibrium. This is achieved through various feedback mechanisms that involve sensors, control centers, and effectors, working together to detect, interpret, and respond to disturbances in the system.

For example, the body maintains homeostasis through mechanisms such as temperature regulation (through sweating or shivering), fluid balance (through kidney function and thirst), and blood glucose levels (through insulin and glucagon secretion). When homeostasis is disrupted, it can lead to disease or dysfunction in the body.

In summary, homeostasis is the maintenance of a stable internal environment within biological systems, through various regulatory mechanisms that respond to changes in external conditions.

T helper 17 (Th17) cells are a subset of CD4+ T cells, which are a type of white blood cell that plays a crucial role in the immune response. Th17 cells are characterized by their production of certain cytokines, including interleukin-17 (IL-17), IL-21, and IL-22. They are involved in the inflammatory response and play a key role in protecting the body against extracellular bacteria and fungi. However, an overactive Th17 response has been implicated in several autoimmune diseases, such as multiple sclerosis, rheumatoid arthritis, and psoriasis. Therefore, understanding the regulation of Th17 cells is important for developing new therapies to treat these conditions.

Down-regulation is a process that occurs in response to various stimuli, where the number or sensitivity of cell surface receptors or the expression of specific genes is decreased. This process helps maintain homeostasis within cells and tissues by reducing the ability of cells to respond to certain signals or molecules.

In the context of cell surface receptors, down-regulation can occur through several mechanisms:

1. Receptor internalization: After binding to their ligands, receptors can be internalized into the cell through endocytosis. Once inside the cell, these receptors may be degraded or recycled back to the cell surface in smaller numbers.
2. Reduced receptor synthesis: Down-regulation can also occur at the transcriptional level, where the expression of genes encoding for specific receptors is decreased, leading to fewer receptors being produced.
3. Receptor desensitization: Prolonged exposure to a ligand can lead to a decrease in receptor sensitivity or affinity, making it more difficult for the cell to respond to the signal.

In the context of gene expression, down-regulation refers to the decreased transcription and/or stability of specific mRNAs, leading to reduced protein levels. This process can be induced by various factors, including microRNA (miRNA)-mediated regulation, histone modification, or DNA methylation.

Down-regulation is an essential mechanism in many physiological processes and can also contribute to the development of several diseases, such as cancer and neurodegenerative disorders.

Antinuclear antibodies (ANA) are a type of autoantibody that target structures found in the nucleus of a cell. These antibodies are produced by the immune system and attack the body's own cells and tissues, leading to inflammation and damage. The presence of ANA is often used as a marker for certain autoimmune diseases, such as systemic lupus erythematosus (SLE), Sjogren's syndrome, rheumatoid arthritis, scleroderma, and polymyositis.

ANA can be detected through a blood test called the antinuclear antibody test. A positive result indicates the presence of ANA in the blood, but it does not necessarily mean that a person has an autoimmune disease. Further testing is usually needed to confirm a diagnosis and determine the specific type of autoantibodies present.

It's important to note that ANA can also be found in healthy individuals, particularly as they age. Therefore, the test results should be interpreted in conjunction with other clinical findings and symptoms.

CD86 is a type of protein found on the surface of certain immune cells called antigen-presenting cells (APCs), such as dendritic cells, macrophages, and B cells. These proteins are known as co-stimulatory molecules and play an important role in activating T cells, a type of white blood cell that is crucial for adaptive immunity.

When APCs encounter a pathogen or foreign substance, they engulf it, break it down into smaller peptides, and display these peptides on their surface in conjunction with another protein called the major histocompatibility complex (MHC) class II molecule. This presentation of antigenic peptides to T cells is not sufficient to activate them fully. Instead, APCs must also provide a co-stimulatory signal through interactions between co-stimulatory molecules like CD86 and receptors on the surface of T cells, such as CD28.

CD86 binds to its receptor CD28 on T cells, providing a critical second signal that promotes T cell activation, proliferation, and differentiation into effector cells. This interaction is essential for the development of an effective immune response against pathogens or foreign substances. In addition to its role in activating T cells, CD86 also helps regulate immune tolerance by contributing to the suppression of self-reactive T cells that could otherwise attack the body's own tissues and cause autoimmune diseases.

Overall, CD86 is an important player in the regulation of the immune response, helping to ensure that T cells are activated appropriately in response to pathogens or foreign substances while also contributing to the maintenance of self-tolerance.

Histocompatibility antigens, class I are proteins found on the surface of most cells in the body. They play a critical role in the immune system's ability to differentiate between "self" and "non-self." These antigens are composed of three polypeptides - two heavy chains and one light chain - and are encoded by genes in the major histocompatibility complex (MHC) on chromosome 6 in humans.

Class I MHC molecules present peptide fragments from inside the cell to CD8+ T cells, also known as cytotoxic T cells. This presentation allows the immune system to detect and destroy cells that have been infected by viruses or other intracellular pathogens, or that have become cancerous.

There are three main types of class I MHC molecules in humans: HLA-A, HLA-B, and HLA-C. The term "HLA" stands for human leukocyte antigen, which reflects the original identification of these proteins on white blood cells (leukocytes). The genes encoding these molecules are highly polymorphic, meaning there are many different variants in the population, and matching HLA types is essential for successful organ transplantation to minimize the risk of rejection.

HLA (Human Leukocyte Antigen) antigens are a group of proteins found on the surface of cells in our body. They play a crucial role in the immune system's ability to differentiate between "self" and "non-self." HLA antigens are encoded by a group of genes located on chromosome 6, known as the major histocompatibility complex (MHC).

There are three types of HLA antigens: HLA class I, HLA class II, and HLA class III. HLA class I antigens are found on the surface of almost all cells in the body and help the immune system recognize and destroy virus-infected or cancerous cells. They consist of three components: HLA-A, HLA-B, and HLA-C.

HLA class II antigens are primarily found on the surface of immune cells, such as macrophages, B cells, and dendritic cells. They assist in the presentation of foreign particles (like bacteria and viruses) to CD4+ T cells, which then activate other parts of the immune system. HLA class II antigens include HLA-DP, HLA-DQ, and HLA-DR.

HLA class III antigens consist of various molecules involved in immune responses, such as cytokines and complement components. They are not directly related to antigen presentation.

The genetic diversity of HLA antigens is extensive, with thousands of variations or alleles. This diversity allows for a better ability to recognize and respond to a wide range of pathogens. However, this variation can also lead to compatibility issues in organ transplantation, as the recipient's immune system may recognize the donor's HLA antigens as foreign and attack the transplanted organ.

Antigens are substances (usually proteins) on the surface of cells, viruses, fungi, or bacteria that can be recognized by the immune system and provoke an immune response. In the context of differentiation, antigens refer to specific markers that identify the developmental stage or lineage of a cell.

Differentiation antigens are proteins or carbohydrates expressed on the surface of cells during various stages of differentiation, which can be used to distinguish between cells at different maturation stages or of different cell types. These antigens play an essential role in the immune system's ability to recognize and respond to abnormal or infected cells while sparing healthy cells.

Examples of differentiation antigens include:

1. CD (cluster of differentiation) molecules: A group of membrane proteins used to identify and define various cell types, such as T cells, B cells, natural killer cells, monocytes, and granulocytes.
2. Lineage-specific antigens: Antigens that are specific to certain cell lineages, such as CD3 for T cells or CD19 for B cells.
3. Maturation markers: Antigens that indicate the maturation stage of a cell, like CD34 and CD38 on hematopoietic stem cells.

Understanding differentiation antigens is crucial in immunology, cancer research, transplantation medicine, and vaccine development.

An animal model in medicine refers to the use of non-human animals in experiments to understand, predict, and test responses and effects of various biological and chemical interactions that may also occur in humans. These models are used when studying complex systems or processes that cannot be easily replicated or studied in human subjects, such as genetic manipulation or exposure to harmful substances. The choice of animal model depends on the specific research question being asked and the similarities between the animal's and human's biological and physiological responses. Examples of commonly used animal models include mice, rats, rabbits, guinea pigs, and non-human primates.

Hemophilia B is a genetic disorder that affects the body's ability to control blood clotting, also known as coagulation. This condition is caused by a deficiency or dysfunction in Factor IX, one of the proteins essential for normal blood clotting. As a result, people with Hemophilia B experience prolonged bleeding and bruising after injuries, surgeries, or spontaneously, particularly in joints and muscles.

There are different degrees of severity, depending on how much Factor IX is missing or not functioning properly. Mild cases may only become apparent after significant trauma, surgery, or tooth extraction, while severe cases can lead to spontaneous bleeding into joints and muscles, causing pain, swelling, and potential long-term damage. Hemophilia B primarily affects males, as it is an X-linked recessive disorder, but females can be carriers of the condition and may experience mild symptoms.

A cell line that is derived from tumor cells and has been adapted to grow in culture. These cell lines are often used in research to study the characteristics of cancer cells, including their growth patterns, genetic changes, and responses to various treatments. They can be established from many different types of tumors, such as carcinomas, sarcomas, and leukemias. Once established, these cell lines can be grown and maintained indefinitely in the laboratory, allowing researchers to conduct experiments and studies that would not be feasible using primary tumor cells. It is important to note that tumor cell lines may not always accurately represent the behavior of the original tumor, as they can undergo genetic changes during their time in culture.

Gene expression is the process by which the information encoded in a gene is used to synthesize a functional gene product, such as a protein or RNA molecule. This process involves several steps: transcription, RNA processing, and translation. During transcription, the genetic information in DNA is copied into a complementary RNA molecule, known as messenger RNA (mRNA). The mRNA then undergoes RNA processing, which includes adding a cap and tail to the mRNA and splicing out non-coding regions called introns. The resulting mature mRNA is then translated into a protein on ribosomes in the cytoplasm through the process of translation.

The regulation of gene expression is a complex and highly controlled process that allows cells to respond to changes in their environment, such as growth factors, hormones, and stress signals. This regulation can occur at various stages of gene expression, including transcriptional activation or repression, RNA processing, mRNA stability, and translation. Dysregulation of gene expression has been implicated in many diseases, including cancer, genetic disorders, and neurological conditions.

Tumor Necrosis Factor-alpha (TNF-α) is a cytokine, a type of small signaling protein involved in immune response and inflammation. It is primarily produced by activated macrophages, although other cell types such as T-cells, natural killer cells, and mast cells can also produce it.

TNF-α plays a crucial role in the body's defense against infection and tissue injury by mediating inflammatory responses, activating immune cells, and inducing apoptosis (programmed cell death) in certain types of cells. It does this by binding to its receptors, TNFR1 and TNFR2, which are found on the surface of many cell types.

In addition to its role in the immune response, TNF-α has been implicated in the pathogenesis of several diseases, including autoimmune disorders such as rheumatoid arthritis, inflammatory bowel disease, and psoriasis, as well as cancer, where it can promote tumor growth and metastasis.

Therapeutic agents that target TNF-α, such as infliximab, adalimumab, and etanercept, have been developed to treat these conditions. However, these drugs can also increase the risk of infections and other side effects, so their use must be carefully monitored.

1. Receptors: In the context of physiology and medicine, receptors are specialized proteins found on the surface of cells or inside cells that detect and respond to specific molecules, known as ligands. These interactions can trigger a variety of responses within the cell, such as starting a signaling cascade or changing the cell's metabolism. Receptors play crucial roles in various biological processes, including communication between cells, regulation of immune responses, and perception of senses.

2. Antigen: An antigen is any substance (usually a protein) that can be recognized by the adaptive immune system, specifically by B-cells and T-cells. Antigens can be derived from various sources, such as microorganisms (like bacteria, viruses, or fungi), pollen, dust mites, or even components of our own cells (for instance, in autoimmune diseases). An antigen's ability to stimulate an immune response is determined by its molecular structure and whether it can be recognized by the receptors on immune cells.

3. B-Cell: B-cells are a type of white blood cell that plays a critical role in the adaptive immune system, particularly in humoral immunity. They originate from hematopoietic stem cells in the bone marrow and are responsible for producing antibodies, which are proteins that recognize and bind to specific antigens. Each B-cell has receptors on its surface called B-cell receptors (BCRs) that can recognize a unique antigen. When a B-cell encounters its specific antigen, it becomes activated, undergoes proliferation, and differentiates into plasma cells that secrete large amounts of antibodies to neutralize or eliminate the antigen.

Bone marrow transplantation (BMT) is a medical procedure in which damaged or destroyed bone marrow is replaced with healthy bone marrow from a donor. Bone marrow is the spongy tissue inside bones that produces blood cells. The main types of BMT are autologous, allogeneic, and umbilical cord blood transplantation.

In autologous BMT, the patient's own bone marrow is used for the transplant. This type of BMT is often used in patients with lymphoma or multiple myeloma who have undergone high-dose chemotherapy or radiation therapy to destroy their cancerous bone marrow.

In allogeneic BMT, bone marrow from a genetically matched donor is used for the transplant. This type of BMT is often used in patients with leukemia, lymphoma, or other blood disorders who have failed other treatments.

Umbilical cord blood transplantation involves using stem cells from umbilical cord blood as a source of healthy bone marrow. This type of BMT is often used in children and adults who do not have a matched donor for allogeneic BMT.

The process of BMT typically involves several steps, including harvesting the bone marrow or stem cells from the donor, conditioning the patient's body to receive the new bone marrow or stem cells, transplanting the new bone marrow or stem cells into the patient's body, and monitoring the patient for signs of engraftment and complications.

BMT is a complex and potentially risky procedure that requires careful planning, preparation, and follow-up care. However, it can be a life-saving treatment for many patients with blood disorders or cancer.

Immunologic cytotoxicity refers to the damage or destruction of cells that occurs as a result of an immune response. This process involves the activation of immune cells, such as cytotoxic T cells and natural killer (NK) cells, which release toxic substances, such as perforins and granzymes, that can kill target cells.

In addition, antibodies produced by B cells can also contribute to immunologic cytotoxicity by binding to antigens on the surface of target cells and triggering complement-mediated lysis or antibody-dependent cellular cytotoxicity (ADCC) by activating immune effector cells.

Immunologic cytotoxicity plays an important role in the body's defense against viral infections, cancer cells, and other foreign substances. However, it can also contribute to tissue damage and autoimmune diseases if the immune system mistakenly targets healthy cells or tissues.

Morphine is a potent opioid analgesic (pain reliever) derived from the opium poppy. It works by binding to opioid receptors in the brain and spinal cord, blocking the transmission of pain signals and reducing the perception of pain. Morphine is used to treat moderate to severe pain, including pain associated with cancer, myocardial infarction, and other conditions. It can also be used as a sedative and cough suppressant.

Morphine has a high potential for abuse and dependence, and its use should be closely monitored by healthcare professionals. Common side effects of morphine include drowsiness, respiratory depression, constipation, nausea, and vomiting. Overdose can result in respiratory failure, coma, and death.

A lymphocyte count is a laboratory test that measures the number of white blood cells called lymphocytes in a sample of blood. Lymphocytes are a vital part of the immune system and help fight off infections and diseases. A normal lymphocyte count ranges from 1,000 to 4,800 cells per microliter (µL) of blood for adults.

An abnormal lymphocyte count can indicate an infection, immune disorder, or blood cancer. A low lymphocyte count is called lymphopenia, while a high lymphocyte count is called lymphocytosis. The cause of an abnormal lymphocyte count should be investigated through further testing and clinical evaluation.

Humoral immunity is a type of immune response in which the body produces proteins called antibodies that circulate in bodily fluids such as blood and help to protect against infection. This form of immunity involves the interaction between antigens (foreign substances that trigger an immune response) and soluble factors, including antibodies, complement proteins, and cytokines.

When a pathogen enters the body, it is recognized as foreign by the immune system, which triggers the production of specific antibodies to bind to and neutralize or destroy the pathogen. These antibodies are produced by B cells, a type of white blood cell that is part of the adaptive immune system.

Humoral immunity provides protection against extracellular pathogens, such as bacteria and viruses, that exist outside of host cells. It is an important component of the body's defense mechanisms and plays a critical role in preventing and fighting off infections.

Bone marrow cells are the types of cells found within the bone marrow, which is the spongy tissue inside certain bones in the body. The main function of bone marrow is to produce blood cells. There are two types of bone marrow: red and yellow. Red bone marrow is where most blood cell production takes place, while yellow bone marrow serves as a fat storage site.

The three main types of bone marrow cells are:

1. Hematopoietic stem cells (HSCs): These are immature cells that can differentiate into any type of blood cell, including red blood cells, white blood cells, and platelets. They have the ability to self-renew, meaning they can divide and create more hematopoietic stem cells.
2. Red blood cell progenitors: These are immature cells that will develop into mature red blood cells, also known as erythrocytes. Red blood cells carry oxygen from the lungs to the body's tissues and carbon dioxide back to the lungs.
3. Myeloid and lymphoid white blood cell progenitors: These are immature cells that will develop into various types of white blood cells, which play a crucial role in the body's immune system by fighting infections and diseases. Myeloid progenitors give rise to granulocytes (neutrophils, eosinophils, and basophils), monocytes, and megakaryocytes (which eventually become platelets). Lymphoid progenitors differentiate into B cells, T cells, and natural killer (NK) cells.

Bone marrow cells are essential for maintaining a healthy blood cell count and immune system function. Abnormalities in bone marrow cells can lead to various medical conditions, such as anemia, leukopenia, leukocytosis, thrombocytopenia, or thrombocytosis, depending on the specific type of blood cell affected. Additionally, bone marrow cells are often used in transplantation procedures to treat patients with certain types of cancer, such as leukemia and lymphoma, or other hematologic disorders.

The intestines, also known as the bowel, are a part of the digestive system that extends from the stomach to the anus. They are responsible for the further breakdown and absorption of nutrients from food, as well as the elimination of waste products. The intestines can be divided into two main sections: the small intestine and the large intestine.

The small intestine is a long, coiled tube that measures about 20 feet in length and is lined with tiny finger-like projections called villi, which increase its surface area and enhance nutrient absorption. The small intestine is where most of the digestion and absorption of nutrients takes place.

The large intestine, also known as the colon, is a wider tube that measures about 5 feet in length and is responsible for absorbing water and electrolytes from digested food, forming stool, and eliminating waste products from the body. The large intestine includes several regions, including the cecum, colon, rectum, and anus.

Together, the intestines play a critical role in maintaining overall health and well-being by ensuring that the body receives the nutrients it needs to function properly.

Phagocytosis is the process by which certain cells in the body, known as phagocytes, engulf and destroy foreign particles, bacteria, or dead cells. This mechanism plays a crucial role in the immune system's response to infection and inflammation. Phagocytes, such as neutrophils, monocytes, and macrophages, have receptors on their surface that recognize and bind to specific molecules (known as antigens) on the target particles or microorganisms.

Once attached, the phagocyte extends pseudopodia (cell extensions) around the particle, forming a vesicle called a phagosome that completely encloses it. The phagosome then fuses with a lysosome, an intracellular organelle containing digestive enzymes and other chemicals. This fusion results in the formation of a phagolysosome, where the engulfed particle is broken down by the action of these enzymes, neutralizing its harmful effects and allowing for the removal of cellular debris or pathogens.

Phagocytosis not only serves as a crucial defense mechanism against infections but also contributes to tissue homeostasis by removing dead cells and debris.

Gene transfer techniques, also known as gene therapy, refer to medical procedures where genetic material is introduced into an individual's cells or tissues to treat or prevent diseases. This can be achieved through various methods:

1. **Viral Vectors**: The most common method uses modified viruses, such as adenoviruses, retroviruses, or lentiviruses, to carry the therapeutic gene into the target cells. The virus infects the cell and inserts the new gene into the cell's DNA.

2. **Non-Viral Vectors**: These include methods like electroporation (using electric fields to create pores in the cell membrane), gene guns (shooting gold particles coated with DNA into cells), or liposomes (tiny fatty bubbles that can enclose DNA).

3. **Direct Injection**: In some cases, the therapeutic gene can be directly injected into a specific tissue or organ.

The goal of gene transfer techniques is to supplement or replace a faulty gene with a healthy one, thereby correcting the genetic disorder. However, these techniques are still largely experimental and have their own set of challenges, including potential immune responses, issues with accurate targeting, and risks of mutations or cancer development.

Cell communication, also known as cell signaling, is the process by which cells exchange and transmit signals between each other and their environment. This complex system allows cells to coordinate their functions and maintain tissue homeostasis. Cell communication can occur through various mechanisms including:

1. Autocrine signaling: When a cell releases a signal that binds to receptors on the same cell, leading to changes in its behavior or function.
2. Paracrine signaling: When a cell releases a signal that binds to receptors on nearby cells, influencing their behavior or function.
3. Endocrine signaling: When a cell releases a hormone into the bloodstream, which then travels to distant target cells and binds to specific receptors, triggering a response.
4. Synaptic signaling: In neurons, communication occurs through the release of neurotransmitters that cross the synapse and bind to receptors on the postsynaptic cell, transmitting electrical or chemical signals.
5. Contact-dependent signaling: When cells physically interact with each other, allowing for the direct exchange of signals and information.

Cell communication is essential for various physiological processes such as growth, development, differentiation, metabolism, immune response, and tissue repair. Dysregulation in cell communication can contribute to diseases, including cancer, diabetes, and neurological disorders.

Biological models, also known as physiological models or organismal models, are simplified representations of biological systems, processes, or mechanisms that are used to understand and explain the underlying principles and relationships. These models can be theoretical (conceptual or mathematical) or physical (such as anatomical models, cell cultures, or animal models). They are widely used in biomedical research to study various phenomena, including disease pathophysiology, drug action, and therapeutic interventions.

Examples of biological models include:

1. Mathematical models: These use mathematical equations and formulas to describe complex biological systems or processes, such as population dynamics, metabolic pathways, or gene regulation networks. They can help predict the behavior of these systems under different conditions and test hypotheses about their underlying mechanisms.
2. Cell cultures: These are collections of cells grown in a controlled environment, typically in a laboratory dish or flask. They can be used to study cellular processes, such as signal transduction, gene expression, or metabolism, and to test the effects of drugs or other treatments on these processes.
3. Animal models: These are living organisms, usually vertebrates like mice, rats, or non-human primates, that are used to study various aspects of human biology and disease. They can provide valuable insights into the pathophysiology of diseases, the mechanisms of drug action, and the safety and efficacy of new therapies.
4. Anatomical models: These are physical representations of biological structures or systems, such as plastic models of organs or tissues, that can be used for educational purposes or to plan surgical procedures. They can also serve as a basis for developing more sophisticated models, such as computer simulations or 3D-printed replicas.

Overall, biological models play a crucial role in advancing our understanding of biology and medicine, helping to identify new targets for therapeutic intervention, develop novel drugs and treatments, and improve human health.

A peptide fragment is a short chain of amino acids that is derived from a larger peptide or protein through various biological or chemical processes. These fragments can result from the natural breakdown of proteins in the body during regular physiological processes, such as digestion, or they can be produced experimentally in a laboratory setting for research or therapeutic purposes.

Peptide fragments are often used in research to map the structure and function of larger peptides and proteins, as well as to study their interactions with other molecules. In some cases, peptide fragments may also have biological activity of their own and can be developed into drugs or diagnostic tools. For example, certain peptide fragments derived from hormones or neurotransmitters may bind to receptors in the body and mimic or block the effects of the full-length molecule.

Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.

Surface antigens are molecules found on the surface of cells that can be recognized by the immune system as being foreign or different from the host's own cells. Antigens are typically proteins or polysaccharides that are capable of stimulating an immune response, leading to the production of antibodies and activation of immune cells such as T-cells.

Surface antigens are important in the context of infectious diseases because they allow the immune system to identify and target infected cells for destruction. For example, viruses and bacteria often display surface antigens that are distinct from those found on host cells, allowing the immune system to recognize and attack them. In some cases, these surface antigens can also be used as targets for vaccines or other immunotherapies.

In addition to their role in infectious diseases, surface antigens are also important in the context of cancer. Tumor cells often display abnormal surface antigens that differ from those found on normal cells, allowing the immune system to potentially recognize and attack them. However, tumors can also develop mechanisms to evade the immune system, making it difficult to mount an effective response.

Overall, understanding the properties and behavior of surface antigens is crucial for developing effective immunotherapies and vaccines against infectious diseases and cancer.

Peptides are short chains of amino acid residues linked by covalent bonds, known as peptide bonds. They are formed when two or more amino acids are joined together through a condensation reaction, which results in the elimination of a water molecule and the formation of an amide bond between the carboxyl group of one amino acid and the amino group of another.

Peptides can vary in length from two to about fifty amino acids, and they are often classified based on their size. For example, dipeptides contain two amino acids, tripeptides contain three, and so on. Oligopeptides typically contain up to ten amino acids, while polypeptides can contain dozens or even hundreds of amino acids.

Peptides play many important roles in the body, including serving as hormones, neurotransmitters, enzymes, and antibiotics. They are also used in medical research and therapeutic applications, such as drug delivery and tissue engineering.

A transgene is a segment of DNA that has been artificially transferred from one organism to another, typically between different species, to introduce a new trait or characteristic. The term "transgene" specifically refers to the genetic material that has been transferred and has become integrated into the host organism's genome. This technology is often used in genetic engineering and biomedical research, including the development of genetically modified organisms (GMOs) for agricultural purposes or the creation of animal models for studying human diseases.

Transgenes can be created using various techniques, such as molecular cloning, where a desired gene is isolated, manipulated, and then inserted into a vector (a small DNA molecule, such as a plasmid) that can efficiently enter the host organism's cells. Once inside the cell, the transgene can integrate into the host genome, allowing for the expression of the new trait in the resulting transgenic organism.

It is important to note that while transgenes can provide valuable insights and benefits in research and agriculture, their use and release into the environment are subjects of ongoing debate due to concerns about potential ecological impacts and human health risks.

Insulin-secreting cells, also known as beta cells, are a type of cell found in the pancreas. They are responsible for producing and releasing insulin, a hormone that regulates blood glucose levels by allowing cells in the body to take in glucose from the bloodstream. Insulin-secreting cells are clustered together in the pancreatic islets, along with other types of cells that produce other hormones such as glucagon and somatostatin. In people with diabetes, these cells may not function properly, leading to an impaired ability to regulate blood sugar levels.

Immunologic receptors are specialized proteins found on the surface of immune cells that recognize and bind to specific molecules, known as antigens, on the surface of pathogens or infected cells. This binding triggers a series of intracellular signaling events that activate the immune cell and initiate an immune response.

There are several types of immunologic receptors, including:

1. T-cell receptors (TCRs): These receptors are found on the surface of T cells and recognize antigens presented in the context of major histocompatibility complex (MHC) molecules.
2. B-cell receptors (BCRs): These receptors are found on the surface of B cells and recognize free antigens in solution.
3. Pattern recognition receptors (PRRs): These receptors are found inside immune cells and recognize conserved molecular patterns associated with pathogens, such as lipopolysaccharides and flagellin.
4. Fc receptors: These receptors are found on the surface of various immune cells and bind to the constant region of antibodies, mediating effector functions such as phagocytosis and antibody-dependent cellular cytotoxicity (ADCC).

Immunologic receptors play a critical role in the recognition and elimination of pathogens and infected cells, and dysregulation of these receptors can lead to immune disorders and diseases.

Acclimatization is the process by which an individual organism adjusts to a change in its environment, enabling it to maintain its normal physiological functions and thus survive and reproduce. In the context of medicine, acclimatization often refers to the body's adaptation to changes in temperature, altitude, or other environmental factors that can affect health.

For example, when a person moves from a low-altitude area to a high-altitude area, their body may undergo several physiological changes to adapt to the reduced availability of oxygen at higher altitudes. These changes may include increased breathing rate and depth, increased heart rate, and altered blood chemistry, among others. This process of acclimatization can take several days or even weeks, depending on the individual and the degree of environmental change.

Similarly, when a person moves from a cold climate to a hot climate, their body may adjust by increasing its sweat production and reducing its heat production, in order to maintain a stable body temperature. This process of acclimatization can help prevent heat-related illnesses such as heat exhaustion and heat stroke.

Overall, acclimatization is an important physiological process that allows organisms to adapt to changing environments and maintain their health and well-being.

Interleukin-2 (IL-2) receptors are a type of cell surface receptor that bind to and interact with the cytokine interleukin-2. IL-2 is a protein that plays an important role in the immune system, particularly in the activation and proliferation of T cells, a type of white blood cell that helps protect the body from infection and disease.

IL-2 receptors are composed of three subunits: alpha (CD25), beta (CD122), and gamma (CD132). These subunits can combine to form different types of IL-2 receptors, each with different functions. The high-affinity IL-2 receptor is made up of all three subunits and is found on the surface of activated T cells. This type of receptor has a strong binding affinity for IL-2 and plays a crucial role in T cell activation and proliferation.

The intermediate-affinity IL-2 receptor, which consists of the beta and gamma subunits, is found on the surface of resting T cells and natural killer (NK) cells. This type of receptor has a lower binding affinity for IL-2 and plays a role in activating and proliferating these cells.

IL-2 receptors are important targets for immunotherapy, as they play a key role in the regulation of the immune response. Drugs that target IL-2 receptors, such as aldesleukin (Proleukin), have been used to treat certain types of cancer and autoimmune diseases.

CD95 (also known as Fas or APO-1) is a type of cell surface receptor that can bind to specific proteins and trigger programmed cell death, also known as apoptosis. It is an important regulator of the immune system and helps to control the activation and deletion of immune cells. CD95 ligand (CD95L), the protein that binds to CD95, is expressed on activated T-cells and can induce apoptosis in other cells that express CD95, including other T-cells and tumor cells.

An antigen is any substance that can stimulate an immune response, leading to the production of antibodies or activation of immune cells. In the context of CD95, antigens may refer to substances that can induce the expression of CD95 on the surface of cells, making them susceptible to CD95L-mediated apoptosis. These antigens could include viral proteins, tumor antigens, or other substances that trigger an immune response.

Therefore, the medical definition of 'antigens, CD95' may refer to substances that can induce the expression of CD95 on the surface of cells and make them targets for CD95L-mediated apoptosis.

SCID mice is an acronym for Severe Combined Immunodeficiency mice. These are genetically modified mice that lack a functional immune system due to the mutation or knockout of several key genes required for immunity. This makes them ideal for studying the human immune system, infectious diseases, and cancer, as well as testing new therapies and treatments in a controlled environment without the risk of interference from the mouse's own immune system. SCID mice are often used in xenotransplantation studies, where human cells or tissues are transplanted into the mouse to study their behavior and interactions with the human immune system.

Cell movement, also known as cell motility, refers to the ability of cells to move independently and change their location within tissue or inside the body. This process is essential for various biological functions, including embryonic development, wound healing, immune responses, and cancer metastasis.

There are several types of cell movement, including:

1. **Crawling or mesenchymal migration:** Cells move by extending and retracting protrusions called pseudopodia or filopodia, which contain actin filaments. This type of movement is common in fibroblasts, immune cells, and cancer cells during tissue invasion and metastasis.
2. **Amoeboid migration:** Cells move by changing their shape and squeezing through tight spaces without forming protrusions. This type of movement is often observed in white blood cells (leukocytes) as they migrate through the body to fight infections.
3. **Pseudopodial extension:** Cells extend pseudopodia, which are temporary cytoplasmic projections containing actin filaments. These protrusions help the cell explore its environment and move forward.
4. **Bacterial flagellar motion:** Bacteria use a whip-like structure called a flagellum to propel themselves through their environment. The rotation of the flagellum is driven by a molecular motor in the bacterial cell membrane.
5. **Ciliary and ependymal movement:** Ciliated cells, such as those lining the respiratory tract and fallopian tubes, have hair-like structures called cilia that beat in coordinated waves to move fluids or mucus across the cell surface.

Cell movement is regulated by a complex interplay of signaling pathways, cytoskeletal rearrangements, and adhesion molecules, which enable cells to respond to environmental cues and navigate through tissues.

Intravenous injections are a type of medical procedure where medication or fluids are administered directly into a vein using a needle and syringe. This route of administration is also known as an IV injection. The solution injected enters the patient's bloodstream immediately, allowing for rapid absorption and onset of action. Intravenous injections are commonly used to provide quick relief from symptoms, deliver medications that are not easily absorbed by other routes, or administer fluids and electrolytes in cases of dehydration or severe illness. It is important that intravenous injections are performed using aseptic technique to minimize the risk of infection.

CD28 is a co-stimulatory molecule that plays an important role in the activation and regulation of T cells, which are key players in the immune response. It is a type of protein found on the surface of T cells and interacts with other proteins called B7-1 (also known as CD80) and B7-2 (also known as CD86) that are expressed on the surface of antigen-presenting cells (APCs).

When a T cell encounters an APC that is presenting an antigen, the T cell receptor (TCR) on the surface of the T cell recognizes and binds to the antigen. However, this interaction alone is not enough to fully activate the T cell. The engagement of CD28 with B7-1 or B7-2 provides a critical co-stimulatory signal that promotes T cell activation, proliferation, and survival.

CD28 is also an important target for immune checkpoint inhibitors, which are drugs used to treat cancer by blocking the inhibitory signals that prevent T cells from attacking tumor cells. By blocking CD28, these drugs can enhance the anti-tumor response of T cells and improve cancer outcomes.

A fetus is the developing offspring in a mammal, from the end of the embryonic period (approximately 8 weeks after fertilization in humans) until birth. In humans, the fetal stage of development starts from the eleventh week of pregnancy and continues until childbirth, which is termed as full-term pregnancy at around 37 to 40 weeks of gestation. During this time, the organ systems become fully developed and the body grows in size. The fetus is surrounded by the amniotic fluid within the amniotic sac and is connected to the placenta via the umbilical cord, through which it receives nutrients and oxygen from the mother. Regular prenatal care is essential during this period to monitor the growth and development of the fetus and ensure a healthy pregnancy and delivery.

The Islets of Langerhans are clusters of specialized cells within the pancreas, an organ located behind the stomach. These islets are named after Paul Langerhans, who first identified them in 1869. They constitute around 1-2% of the total mass of the pancreas and are distributed throughout its substance.

The Islets of Langerhans contain several types of cells, including:

1. Alpha (α) cells: These produce and release glucagon, a hormone that helps to regulate blood sugar levels by promoting the conversion of glycogen to glucose in the liver when blood sugar levels are low.
2. Beta (β) cells: These produce and release insulin, a hormone that promotes the uptake and utilization of glucose by cells throughout the body, thereby lowering blood sugar levels.
3. Delta (δ) cells: These produce and release somatostatin, a hormone that inhibits the release of both insulin and glucagon and helps regulate their secretion in response to changing blood sugar levels.
4. PP cells (gamma or γ cells): These produce and release pancreatic polypeptide, which plays a role in regulating digestive enzyme secretion and gastrointestinal motility.

Dysfunction of the Islets of Langerhans can lead to various endocrine disorders, such as diabetes mellitus, where insulin-producing beta cells are damaged or destroyed, leading to impaired blood sugar regulation.

The immune system processes refer to the complex series of interactions and reactions involving various cells, tissues, organs, and systems in the body that protect against harmful pathogens (such as bacteria, viruses, fungi, and parasites) and toxic substances, while also maintaining tolerance to self and non-harmful environmental antigens. The immune system can be divided into two major components: the innate immune system, which provides a rapid, non-specific response to threats; and the adaptive immune system, which offers a slower, more specific and targeted response that improves with repeated exposure to pathogens.

The main processes of the immune system include:

1. Recognition of foreign substances (antigens) by immune cells such as macrophages, dendritic cells, and B cells.
2. Activation and proliferation of immune cells, including T cells and B cells, to eliminate the identified threats.
3. Secretion of various cytokines, chemokines, and other signaling molecules that coordinate the immune response and recruit additional effector cells.
4. Elimination of pathogens through various mechanisms, such as phagocytosis (engulfing and digesting), cytotoxicity (directly killing infected cells), and antibody-mediated neutralization or complement activation.
5. Development of immunological memory in the adaptive immune system, allowing for faster and more effective responses to subsequent encounters with the same pathogen.
6. Maintenance of self-tolerance, preventing the immune system from attacking the body's own cells and tissues.
7. Regulation of inflammation, ensuring that the immune response is appropriate and does not cause excessive tissue damage.
8. Interaction with other systems in the body, such as the nervous and endocrine systems, to maintain overall homeostasis and health.

Adoptive immunotherapy is a type of cancer treatment that involves the removal of immune cells from a patient, followed by their modification and expansion in the laboratory, and then reinfusion back into the patient to help boost their immune system's ability to fight cancer. This approach can be used to enhance the natural ability of T-cells (a type of white blood cell) to recognize and destroy cancer cells.

There are different types of adoptive immunotherapy, including:

1. T-cell transfer therapy: In this approach, T-cells are removed from the patient's tumor or blood, activated and expanded in the laboratory, and then reinfused back into the patient. Some forms of T-cell transfer therapy involve genetically modifying the T-cells to express chimeric antigen receptors (CARs) that recognize specific proteins on the surface of cancer cells.
2. Tumor-infiltrating lymphocyte (TIL) therapy: This type of adoptive immunotherapy involves removing T-cells directly from a patient's tumor, expanding them in the laboratory, and then reinfusing them back into the patient. The expanded T-cells are specifically targeted to recognize and destroy cancer cells.
3. Dendritic cell (DC) vaccine: DCs are specialized immune cells that help activate T-cells. In this approach, DCs are removed from the patient, exposed to tumor antigens in the laboratory, and then reinfused back into the patient to stimulate a stronger immune response against cancer cells.

Adoptive immunotherapy has shown promise in treating certain types of cancer, such as melanoma and leukemia, but more research is needed to determine its safety and efficacy in other types of cancer.

I cannot provide a specific medical definition for "Melanoma, Experimental," as it is not a standardized medical term. However, I can give you information about melanoma and experimental treatments related to this disease.

Melanoma is a type of cancer that develops from pigment-producing cells known as melanocytes. It usually occurs in the skin but can rarely occur in other parts of the body, such as the eyes or internal organs. Melanoma is characterized by the uncontrolled growth and multiplication of melanocytes, forming malignant tumors.

Experimental treatments for melanoma refer to novel therapeutic strategies that are currently being researched and tested in clinical trials. These experimental treatments may include:

1. Targeted therapies: Drugs that target specific genetic mutations or molecular pathways involved in melanoma growth and progression. Examples include BRAF and MEK inhibitors, such as vemurafenib, dabrafenib, and trametinib.
2. Immunotherapies: Treatments designed to enhance the immune system's ability to recognize and destroy cancer cells. These may include checkpoint inhibitors (e.g., ipilimumab, nivolumab, pembrolizumab), adoptive cell therapies (e.g., CAR T-cell therapy), and therapeutic vaccines.
3. Oncolytic viruses: Genetically modified viruses that can selectively infect and kill cancer cells while leaving healthy cells unharmed. Talimogene laherparepvec (T-VEC) is an example of an oncolytic virus approved for the treatment of advanced melanoma.
4. Combination therapies: The use of multiple experimental treatments in combination to improve efficacy and reduce the risk of resistance. For instance, combining targeted therapies with immunotherapies or different types of immunotherapies.
5. Personalized medicine approaches: Using genetic testing and biomarker analysis to identify the most effective treatment for an individual patient based on their specific tumor characteristics.

It is essential to consult with healthcare professionals and refer to clinical trial databases, such as ClinicalTrials.gov, for up-to-date information on experimental treatments for melanoma.

Membrane proteins are a type of protein that are embedded in the lipid bilayer of biological membranes, such as the plasma membrane of cells or the inner membrane of mitochondria. These proteins play crucial roles in various cellular processes, including:

1. Cell-cell recognition and signaling
2. Transport of molecules across the membrane (selective permeability)
3. Enzymatic reactions at the membrane surface
4. Energy transduction and conversion
5. Mechanosensation and signal transduction

Membrane proteins can be classified into two main categories: integral membrane proteins, which are permanently associated with the lipid bilayer, and peripheral membrane proteins, which are temporarily or loosely attached to the membrane surface. Integral membrane proteins can further be divided into three subcategories based on their topology:

1. Transmembrane proteins, which span the entire width of the lipid bilayer with one or more alpha-helices or beta-barrels.
2. Lipid-anchored proteins, which are covalently attached to lipids in the membrane via a glycosylphosphatidylinositol (GPI) anchor or other lipid modifications.
3. Monotopic proteins, which are partially embedded in the membrane and have one or more domains exposed to either side of the bilayer.

Membrane proteins are essential for maintaining cellular homeostasis and are targets for various therapeutic interventions, including drug development and gene therapy. However, their structural complexity and hydrophobicity make them challenging to study using traditional biochemical methods, requiring specialized techniques such as X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and single-particle cryo-electron microscopy (cryo-EM).

Insulin resistance is a condition in which the body's cells become less responsive to insulin, a hormone produced by the pancreas that regulates blood sugar levels. In response to this decreased sensitivity, the pancreas produces more insulin to help glucose enter the cells. However, over time, the pancreas may not be able to keep up with the increased demand for insulin, leading to high levels of glucose in the blood and potentially resulting in type 2 diabetes, prediabetes, or other health issues such as metabolic syndrome, cardiovascular disease, and non-alcoholic fatty liver disease. Insulin resistance is often associated with obesity, physical inactivity, and genetic factors.

Glutamate decarboxylase (GAD) is an enzyme that plays a crucial role in the synthesis of the neurotransmitter gamma-aminobutyric acid (GABA) in the brain. GABA is an inhibitory neurotransmitter that helps to balance the excitatory effects of glutamate, another neurotransmitter.

Glutamate decarboxylase catalyzes the conversion of glutamate to GABA by removing a carboxyl group from the glutamate molecule. This reaction occurs in two steps, with the enzyme first converting glutamate to glutamic acid semialdehyde and then converting that intermediate product to GABA.

There are two major isoforms of glutamate decarboxylase, GAD65 and GAD67, which differ in their molecular weight, subcellular localization, and function. GAD65 is primarily responsible for the synthesis of GABA in neuronal synapses, while GAD67 is responsible for the synthesis of GABA in the cell body and dendrites of neurons.

Glutamate decarboxylase is an important target for research in neurology and psychiatry because dysregulation of GABAergic neurotransmission has been implicated in a variety of neurological and psychiatric disorders, including epilepsy, anxiety, depression, and schizophrenia.

Salt-tolerant plants, also known as halophytes, are plants that can grow and complete their life cycle in saline environments. These plants have specialized adaptations that allow them to survive and reproduce in the presence of high concentrations of salt, particularly sodium chloride (NaCl), which is toxic to most plants.

Salt tolerance in plants is a complex trait that involves various physiological and biochemical mechanisms, such as:

1. Exclusion: Preventing the uptake of excess salt by the roots or excluding it from entering the plant cells.
2. Compartmentalization: Storing excess salt in vacuoles or older leaves that can be shed to reduce the overall salt load.
3. Tissue tolerance: Adapting to high salt concentrations within the plant tissues without experiencing toxicity or osmotic stress.
4. Osmoregulation: Maintaining water balance and cell turgor by synthesizing and accumulating compatible solutes, such as proline and glycine betaine, which help to lower the osmotic potential of the cells.
5. Ion homeostasis: Regulating the uptake and distribution of essential ions, like potassium (K+), while minimizing the accumulation of toxic ions, such as sodium (Na+) and chloride (Cl-).

Examples of salt-tolerant plants include mangroves, sea grasses, cordgrass, glasswort, and certain species of cacti and succulents. These plants have significant ecological and agricultural importance in coastal areas and arid regions, where salinity is a major environmental constraint.

Antibodies, viral are proteins produced by the immune system in response to an infection with a virus. These antibodies are capable of recognizing and binding to specific antigens on the surface of the virus, which helps to neutralize or destroy the virus and prevent its replication. Once produced, these antibodies can provide immunity against future infections with the same virus.

Viral antibodies are typically composed of four polypeptide chains - two heavy chains and two light chains - that are held together by disulfide bonds. The binding site for the antigen is located at the tip of the Y-shaped structure, formed by the variable regions of the heavy and light chains.

There are five classes of antibodies in humans: IgA, IgD, IgE, IgG, and IgM. Each class has a different function and is distributed differently throughout the body. For example, IgG is the most common type of antibody found in the bloodstream and provides long-term immunity against viruses, while IgA is found primarily in mucous membranes and helps to protect against respiratory and gastrointestinal infections.

In addition to their role in the immune response, viral antibodies can also be used as diagnostic tools to detect the presence of a specific virus in a patient's blood or other bodily fluids.

Genetically modified plants (GMPs) are plants that have had their DNA altered through genetic engineering techniques to exhibit desired traits. These modifications can be made to enhance certain characteristics such as increased resistance to pests, improved tolerance to environmental stresses like drought or salinity, or enhanced nutritional content. The process often involves introducing genes from other organisms, such as bacteria or viruses, into the plant's genome. Examples of GMPs include Bt cotton, which has a gene from the bacterium Bacillus thuringiensis that makes it resistant to certain pests, and golden rice, which is engineered to contain higher levels of beta-carotene, a precursor to vitamin A. It's important to note that genetically modified plants are subject to rigorous testing and regulation to ensure their safety for human consumption and environmental impact before they are approved for commercial use.

Sodium Chloride is defined as the inorganic compound with the chemical formula NaCl, representing a 1:1 ratio of sodium and chloride ions. It is commonly known as table salt or halite, and it is used extensively in food seasoning and preservation due to its ability to enhance flavor and inhibit bacterial growth. In medicine, sodium chloride is used as a balanced electrolyte solution for rehydration and as a topical wound irrigant and antiseptic. It is also an essential component of the human body's fluid balance and nerve impulse transmission.

According to the medical definition, ultraviolet (UV) rays are invisible radiations that fall in the range of the electromagnetic spectrum between 100-400 nanometers. UV rays are further divided into three categories: UVA (320-400 nm), UVB (280-320 nm), and UVC (100-280 nm).

UV rays have various sources, including the sun and artificial sources like tanning beds. Prolonged exposure to UV rays can cause damage to the skin, leading to premature aging, eye damage, and an increased risk of skin cancer. UVA rays penetrate deeper into the skin and are associated with skin aging, while UVB rays primarily affect the outer layer of the skin and are linked to sunburns and skin cancer. UVC rays are the most harmful but fortunately, they are absorbed by the Earth's atmosphere and do not reach the surface.

Healthcare professionals recommend limiting exposure to UV rays, wearing protective clothing, using broad-spectrum sunscreen with an SPF of at least 30, and avoiding tanning beds to reduce the risk of UV-related health problems.

Western blotting is a laboratory technique used in molecular biology to detect and quantify specific proteins in a mixture of many different proteins. This technique is commonly used to confirm the expression of a protein of interest, determine its size, and investigate its post-translational modifications. The name "Western" blotting distinguishes this technique from Southern blotting (for DNA) and Northern blotting (for RNA).

The Western blotting procedure involves several steps:

1. Protein extraction: The sample containing the proteins of interest is first extracted, often by breaking open cells or tissues and using a buffer to extract the proteins.
2. Separation of proteins by electrophoresis: The extracted proteins are then separated based on their size by loading them onto a polyacrylamide gel and running an electric current through the gel (a process called sodium dodecyl sulfate-polyacrylamide gel electrophoresis or SDS-PAGE). This separates the proteins according to their molecular weight, with smaller proteins migrating faster than larger ones.
3. Transfer of proteins to a membrane: After separation, the proteins are transferred from the gel onto a nitrocellulose or polyvinylidene fluoride (PVDF) membrane using an electric current in a process called blotting. This creates a replica of the protein pattern on the gel but now immobilized on the membrane for further analysis.
4. Blocking: The membrane is then blocked with a blocking agent, such as non-fat dry milk or bovine serum albumin (BSA), to prevent non-specific binding of antibodies in subsequent steps.
5. Primary antibody incubation: A primary antibody that specifically recognizes the protein of interest is added and allowed to bind to its target protein on the membrane. This step may be performed at room temperature or 4°C overnight, depending on the antibody's properties.
6. Washing: The membrane is washed with a buffer to remove unbound primary antibodies.
7. Secondary antibody incubation: A secondary antibody that recognizes the primary antibody (often coupled to an enzyme or fluorophore) is added and allowed to bind to the primary antibody. This step may involve using a horseradish peroxidase (HRP)-conjugated or alkaline phosphatase (AP)-conjugated secondary antibody, depending on the detection method used later.
8. Washing: The membrane is washed again to remove unbound secondary antibodies.
9. Detection: A detection reagent is added to visualize the protein of interest by detecting the signal generated from the enzyme-conjugated or fluorophore-conjugated secondary antibody. This can be done using chemiluminescent, colorimetric, or fluorescent methods.
10. Analysis: The resulting image is analyzed to determine the presence and quantity of the protein of interest in the sample.

Western blotting is a powerful technique for identifying and quantifying specific proteins within complex mixtures. It can be used to study protein expression, post-translational modifications, protein-protein interactions, and more. However, it requires careful optimization and validation to ensure accurate and reproducible results.

Immunoglobulin M (IgM) is a type of antibody that is primarily found in the blood and lymph fluid. It is the first antibody to be produced in response to an initial exposure to an antigen, making it an important part of the body's primary immune response. IgM antibodies are large molecules that are composed of five basic units, giving them a pentameric structure. They are primarily found on the surface of B cells as membrane-bound immunoglobulins (mlgM), where they function as receptors for antigens. Once an mlgM receptor binds to an antigen, it triggers the activation and differentiation of the B cell into a plasma cell that produces and secretes large amounts of soluble IgM antibodies.

IgM antibodies are particularly effective at agglutination (clumping) and complement activation, which makes them important in the early stages of an immune response to help clear pathogens from the bloodstream. However, they are not as stable or long-lived as other types of antibodies, such as IgG, and their levels tend to decline after the initial immune response has occurred.

In summary, Immunoglobulin M (IgM) is a type of antibody that plays a crucial role in the primary immune response to antigens by agglutination and complement activation. It is primarily found in the blood and lymph fluid, and it is produced by B cells after they are activated by an antigen.

"Freezing" is a term used in the medical field to describe a phenomenon that can occur in certain neurological conditions, most notably in Parkinson's disease. It refers to a sudden and temporary inability to move or initiate movement, often triggered by environmental factors such as narrow spaces, turning, or approaching a destination. This can increase the risk of falls and make daily activities challenging for affected individuals.

Freezing is also known as "freezing of gait" (FOG) when it specifically affects a person's ability to walk. During FOG episodes, the person may feel like their feet are glued to the ground, making it difficult to take steps forward. This can be very distressing and debilitating for those affected.

It is important to note that "freezing" has different meanings in different medical contexts, such as in the field of orthopedics, where it may refer to a loss of joint motion due to stiffness or inflammation. Always consult with a healthcare professional for accurate information tailored to your specific situation.

Gene expression regulation in plants refers to the processes that control the production of proteins and RNA from the genes present in the plant's DNA. This regulation is crucial for normal growth, development, and response to environmental stimuli in plants. It can occur at various levels, including transcription (the first step in gene expression, where the DNA sequence is copied into RNA), RNA processing (such as alternative splicing, which generates different mRNA molecules from a single gene), translation (where the information in the mRNA is used to produce a protein), and post-translational modification (where proteins are chemically modified after they have been synthesized).

In plants, gene expression regulation can be influenced by various factors such as hormones, light, temperature, and stress. Plants use complex networks of transcription factors, chromatin remodeling complexes, and small RNAs to regulate gene expression in response to these signals. Understanding the mechanisms of gene expression regulation in plants is important for basic research, as well as for developing crops with improved traits such as increased yield, stress tolerance, and disease resistance.

Salinity is not a term that has a specific medical definition. However, in general terms, salinity refers to the level of salt or sodium content in a substance, usually measured in parts per thousand (ppt). In a medical context, salinity might be discussed in relation to things like the body's fluid balance or the composition of certain bodily fluids, such as sweat or tears.

It is worth noting that in some cases, high salinity levels can have negative effects on health. For example, consuming water with very high salt content can lead to dehydration and electrolyte imbalances, which can be dangerous. Similarly, exposure to high-salinity environments (such as seawater) can cause skin irritation and other problems in some people. However, these are not direct medical definitions of salinity.

The placenta is an organ that develops in the uterus during pregnancy and provides oxygen and nutrients to the growing baby through the umbilical cord. It also removes waste products from the baby's blood. The placenta attaches to the wall of the uterus, and the baby's side of the placenta contains many tiny blood vessels that connect to the baby's circulatory system. This allows for the exchange of oxygen, nutrients, and waste between the mother's and baby's blood. After the baby is born, the placenta is usually expelled from the uterus in a process called afterbirth.

Fas Ligand Protein (FasL or CD95L) is a type II transmembrane protein belonging to the tumor necrosis factor (TNF) superfamily. It plays a crucial role in programmed cell death, also known as apoptosis. The FasL protein binds to its receptor, Fas (CD95 or APO-1), which is found on the surface of various cells including immune cells. This binding triggers a signaling cascade that leads to apoptosis, helping to regulate the immune response and maintain homeostasis in tissues.

FasL can also be produced as a soluble protein (sFasL) through alternative splicing or proteolytic cleavage of the membrane-bound form. Soluble FasL may have different functions compared to its membrane-bound counterpart, and its role in physiology and disease is still under investigation.

Dysregulation of the Fas/FasL system has been implicated in various pathological conditions, including autoimmune diseases, neurodegenerative disorders, and cancer.

Analgesics, opioid are a class of drugs used for the treatment of pain. They work by binding to specific receptors in the brain and spinal cord, blocking the transmission of pain signals to the brain. Opioids can be synthetic or natural, and include drugs such as morphine, codeine, oxycodone, hydrocodone, hydromorphone, fentanyl, and methadone. They are often used for moderate to severe pain, such as that resulting from injury, surgery, or chronic conditions like cancer. However, opioids can also produce euphoria, physical dependence, and addiction, so they are tightly regulated and carry a risk of misuse.

Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) is a laboratory technique used in molecular biology to amplify and detect specific DNA sequences. This technique is particularly useful for the detection and quantification of RNA viruses, as well as for the analysis of gene expression.

The process involves two main steps: reverse transcription and polymerase chain reaction (PCR). In the first step, reverse transcriptase enzyme is used to convert RNA into complementary DNA (cDNA) by reading the template provided by the RNA molecule. This cDNA then serves as a template for the PCR amplification step.

In the second step, the PCR reaction uses two primers that flank the target DNA sequence and a thermostable polymerase enzyme to repeatedly copy the targeted cDNA sequence. The reaction mixture is heated and cooled in cycles, allowing the primers to anneal to the template, and the polymerase to extend the new strand. This results in exponential amplification of the target DNA sequence, making it possible to detect even small amounts of RNA or cDNA.

RT-PCR is a sensitive and specific technique that has many applications in medical research and diagnostics, including the detection of viruses such as HIV, hepatitis C virus, and SARS-CoV-2 (the virus that causes COVID-19). It can also be used to study gene expression, identify genetic mutations, and diagnose genetic disorders.

Immunoglobulin A (IgA) is a type of antibody that plays a crucial role in the immune function of the human body. It is primarily found in external secretions, such as saliva, tears, breast milk, and sweat, as well as in mucous membranes lining the respiratory and gastrointestinal tracts. IgA exists in two forms: a monomeric form found in serum and a polymeric form found in secretions.

The primary function of IgA is to provide immune protection at mucosal surfaces, which are exposed to various environmental antigens, such as bacteria, viruses, parasites, and allergens. By doing so, it helps prevent the entry and colonization of pathogens into the body, reducing the risk of infections and inflammation.

IgA functions by binding to antigens present on the surface of pathogens or allergens, forming immune complexes that can neutralize their activity. These complexes are then transported across the epithelial cells lining mucosal surfaces and released into the lumen, where they prevent the adherence and invasion of pathogens.

In summary, Immunoglobulin A (IgA) is a vital antibody that provides immune defense at mucosal surfaces by neutralizing and preventing the entry of harmful antigens into the body.

Disease progression is the worsening or advancement of a medical condition over time. It refers to the natural course of a disease, including its development, the severity of symptoms and complications, and the impact on the patient's overall health and quality of life. Understanding disease progression is important for developing appropriate treatment plans, monitoring response to therapy, and predicting outcomes.

The rate of disease progression can vary widely depending on the type of medical condition, individual patient factors, and the effectiveness of treatment. Some diseases may progress rapidly over a short period of time, while others may progress more slowly over many years. In some cases, disease progression may be slowed or even halted with appropriate medical interventions, while in other cases, the progression may be inevitable and irreversible.

In clinical practice, healthcare providers closely monitor disease progression through regular assessments, imaging studies, and laboratory tests. This information is used to guide treatment decisions and adjust care plans as needed to optimize patient outcomes and improve quality of life.

Gene expression profiling is a laboratory technique used to measure the activity (expression) of thousands of genes at once. This technique allows researchers and clinicians to identify which genes are turned on or off in a particular cell, tissue, or organism under specific conditions, such as during health, disease, development, or in response to various treatments.

The process typically involves isolating RNA from the cells or tissues of interest, converting it into complementary DNA (cDNA), and then using microarray or high-throughput sequencing technologies to determine which genes are expressed and at what levels. The resulting data can be used to identify patterns of gene expression that are associated with specific biological states or processes, providing valuable insights into the underlying molecular mechanisms of diseases and potential targets for therapeutic intervention.

In recent years, gene expression profiling has become an essential tool in various fields, including cancer research, drug discovery, and personalized medicine, where it is used to identify biomarkers of disease, predict patient outcomes, and guide treatment decisions.

Clinical trials are research studies that involve human participants and are designed to evaluate the safety and efficacy of new medical treatments, drugs, devices, or behavioral interventions. The purpose of clinical trials is to determine whether a new intervention is safe, effective, and beneficial for patients, as well as to compare it with currently available treatments. Clinical trials follow a series of phases, each with specific goals and criteria, before a new intervention can be approved by regulatory authorities for widespread use.

Clinical trials are conducted according to a protocol, which is a detailed plan that outlines the study's objectives, design, methodology, statistical analysis, and ethical considerations. The protocol is developed and reviewed by a team of medical experts, statisticians, and ethicists, and it must be approved by an institutional review board (IRB) before the trial can begin.

Participation in clinical trials is voluntary, and participants must provide informed consent before enrolling in the study. Informed consent involves providing potential participants with detailed information about the study's purpose, procedures, risks, benefits, and alternatives, as well as their rights as research subjects. Participants can withdraw from the study at any time without penalty or loss of benefits to which they are entitled.

Clinical trials are essential for advancing medical knowledge and improving patient care. They help researchers identify new treatments, diagnostic tools, and prevention strategies that can benefit patients and improve public health. However, clinical trials also pose potential risks to participants, including adverse effects from experimental interventions, time commitment, and inconvenience. Therefore, it is important for researchers to carefully design and conduct clinical trials to minimize risks and ensure that the benefits outweigh the risks.

Mononuclear leukocytes are a type of white blood cells (leukocytes) that have a single, large nucleus. They include lymphocytes (B-cells, T-cells, and natural killer cells), monocytes, and dendritic cells. These cells play important roles in the body's immune system, including defending against infection and disease, and participating in immune responses and surveillance. Mononuclear leukocytes can be found in the bloodstream as well as in tissues throughout the body. They are involved in both innate and adaptive immunity, providing specific and nonspecific defense mechanisms to protect the body from harmful pathogens and other threats.

Passive immunization is a type of temporary immunity that is transferred to an individual through the injection of antibodies produced outside of the body, rather than through the active production of antibodies in the body in response to vaccination or infection. This can be done through the administration of preformed antibodies, such as immune globulins, which contain a mixture of antibodies that provide immediate protection against specific diseases.

Passive immunization is often used in situations where individuals have been exposed to a disease and do not have time to develop their own active immune response, or in cases where individuals are unable to produce an adequate immune response due to certain medical conditions. It can also be used as a short-term measure to provide protection until an individual can receive a vaccination that will confer long-term immunity.

Passive immunization provides immediate protection against disease, but the protection is typically short-lived, lasting only a few weeks or months. This is because the transferred antibodies are gradually broken down and eliminated by the body over time. In contrast, active immunization confers long-term immunity through the production of memory cells that can mount a rapid and effective immune response upon re-exposure to the same pathogen in the future.

Immunoglobulins (Igs), also known as antibodies, are glycoprotein molecules produced by the immune system's B cells in response to the presence of foreign substances, such as bacteria, viruses, and toxins. These Y-shaped proteins play a crucial role in identifying and neutralizing pathogens and other antigens, thereby protecting the body against infection and disease.

Immunoglobulins are composed of four polypeptide chains: two identical heavy chains and two identical light chains, held together by disulfide bonds. The variable regions of these chains form the antigen-binding sites, which recognize and bind to specific epitopes on antigens. Based on their heavy chain type, immunoglobulins are classified into five main isotypes or classes: IgA, IgD, IgE, IgG, and IgM. Each class has distinct functions in the immune response, such as providing protection in different body fluids and tissues, mediating hypersensitivity reactions, and aiding in the development of immunological memory.

In medical settings, immunoglobulins can be administered therapeutically to provide passive immunity against certain diseases or to treat immune deficiencies, autoimmune disorders, and other conditions that may benefit from immunomodulation.

Central tolerance is a term used in immunology to describe the process by which the immune system learns to tolerate self-antigens, or the proteins and other molecules that are produced by an individual's own cells and tissues. This is an important mechanism for preventing autoimmune diseases, in which the immune system mistakenly attacks the body's own cells and tissues.

Central tolerance is established in the primary lymphoid organs, such as the bone marrow and thymus, during the development of T cells and B cells, which are the white blood cells that play a central role in the adaptive immune response. In the bone marrow, developing B cells that recognize self-antigens are either eliminated or rendered unresponsive (a process called receptor editing). In the thymus, developing T cells that recognize self-antigens are also eliminated or rendered unresponsive through a process called negative selection.

Central tolerance is an important mechanism for preventing autoimmunity, but it is not perfect. Some self-reactive T cells and B cells may escape these processes and enter the peripheral immune system, where they can potentially cause damage if they are activated by self-antigens. To prevent this from happening, the immune system has additional mechanisms of tolerance, called peripheral tolerance, that help to keep these self-reactive cells in check.

Bacterial antibodies are a type of antibodies produced by the immune system in response to an infection caused by bacteria. These antibodies are proteins that recognize and bind to specific antigens on the surface of the bacterial cells, marking them for destruction by other immune cells. Bacterial antibodies can be classified into several types based on their structure and function, including IgG, IgM, IgA, and IgE. They play a crucial role in the body's defense against bacterial infections and provide immunity to future infections with the same bacteria.

A biological marker, often referred to as a biomarker, is a measurable indicator that reflects the presence or severity of a disease state, or a response to a therapeutic intervention. Biomarkers can be found in various materials such as blood, tissues, or bodily fluids, and they can take many forms, including molecular, histologic, radiographic, or physiological measurements.

In the context of medical research and clinical practice, biomarkers are used for a variety of purposes, such as:

1. Diagnosis: Biomarkers can help diagnose a disease by indicating the presence or absence of a particular condition. For example, prostate-specific antigen (PSA) is a biomarker used to detect prostate cancer.
2. Monitoring: Biomarkers can be used to monitor the progression or regression of a disease over time. For instance, hemoglobin A1c (HbA1c) levels are monitored in diabetes patients to assess long-term blood glucose control.
3. Predicting: Biomarkers can help predict the likelihood of developing a particular disease or the risk of a negative outcome. For example, the presence of certain genetic mutations can indicate an increased risk for breast cancer.
4. Response to treatment: Biomarkers can be used to evaluate the effectiveness of a specific treatment by measuring changes in the biomarker levels before and after the intervention. This is particularly useful in personalized medicine, where treatments are tailored to individual patients based on their unique biomarker profiles.

It's important to note that for a biomarker to be considered clinically valid and useful, it must undergo rigorous validation through well-designed studies, including demonstrating sensitivity, specificity, reproducibility, and clinical relevance.

Cell division is the process by which a single eukaryotic cell (a cell with a true nucleus) divides into two identical daughter cells. This complex process involves several stages, including replication of DNA, separation of chromosomes, and division of the cytoplasm. There are two main types of cell division: mitosis and meiosis.

Mitosis is the type of cell division that results in two genetically identical daughter cells. It is a fundamental process for growth, development, and tissue repair in multicellular organisms. The stages of mitosis include prophase, prometaphase, metaphase, anaphase, and telophase, followed by cytokinesis, which divides the cytoplasm.

Meiosis, on the other hand, is a type of cell division that occurs in the gonads (ovaries and testes) during the production of gametes (sex cells). Meiosis results in four genetically unique daughter cells, each with half the number of chromosomes as the parent cell. This process is essential for sexual reproduction and genetic diversity. The stages of meiosis include meiosis I and meiosis II, which are further divided into prophase, prometaphase, metaphase, anaphase, and telophase.

In summary, cell division is the process by which a single cell divides into two daughter cells, either through mitosis or meiosis. This process is critical for growth, development, tissue repair, and sexual reproduction in multicellular organisms.

A dose-response relationship in the context of drugs refers to the changes in the effects or symptoms that occur as the dose of a drug is increased or decreased. Generally, as the dose of a drug is increased, the severity or intensity of its effects also increases. Conversely, as the dose is decreased, the effects of the drug become less severe or may disappear altogether.

The dose-response relationship is an important concept in pharmacology and toxicology because it helps to establish the safe and effective dosage range for a drug. By understanding how changes in the dose of a drug affect its therapeutic and adverse effects, healthcare providers can optimize treatment plans for their patients while minimizing the risk of harm.

The dose-response relationship is typically depicted as a curve that shows the relationship between the dose of a drug and its effect. The shape of the curve may vary depending on the drug and the specific effect being measured. Some drugs may have a steep dose-response curve, meaning that small changes in the dose can result in large differences in the effect. Other drugs may have a more gradual dose-response curve, where larger changes in the dose are needed to produce significant effects.

In addition to helping establish safe and effective dosages, the dose-response relationship is also used to evaluate the potential therapeutic benefits and risks of new drugs during clinical trials. By systematically testing different doses of a drug in controlled studies, researchers can identify the optimal dosage range for the drug and assess its safety and efficacy.

Host-pathogen interactions refer to the complex and dynamic relationship between a living organism (the host) and a disease-causing agent (the pathogen). This interaction can involve various molecular, cellular, and physiological processes that occur between the two entities. The outcome of this interaction can determine whether the host will develop an infection or not, as well as the severity and duration of the illness.

During host-pathogen interactions, the pathogen may release virulence factors that allow it to evade the host's immune system, colonize tissues, and obtain nutrients for its survival and replication. The host, in turn, may mount an immune response to recognize and eliminate the pathogen, which can involve various mechanisms such as inflammation, phagocytosis, and the production of antimicrobial agents.

Understanding the intricacies of host-pathogen interactions is crucial for developing effective strategies to prevent and treat infectious diseases. This knowledge can help identify new targets for therapeutic interventions, inform vaccine design, and guide public health policies to control the spread of infectious agents.

"Cold temperature" is a relative term and its definition can vary depending on the context. In general, it refers to temperatures that are lower than those normally experienced or preferred by humans and other warm-blooded animals. In a medical context, cold temperature is often defined as an environmental temperature that is below 16°C (60.8°F).

Exposure to cold temperatures can have various physiological effects on the human body, such as vasoconstriction of blood vessels near the skin surface, increased heart rate and metabolic rate, and shivering, which helps to generate heat and maintain body temperature. Prolonged exposure to extreme cold temperatures can lead to hypothermia, a potentially life-threatening condition characterized by a drop in core body temperature below 35°C (95°F).

It's worth noting that some people may have different sensitivities to cold temperatures due to factors such as age, health status, and certain medical conditions. For example, older adults, young children, and individuals with circulatory or neurological disorders may be more susceptible to the effects of cold temperatures.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

Heterologous transplantation is a type of transplantation where an organ or tissue is transferred from one species to another. This is in contrast to allogeneic transplantation, where the donor and recipient are of the same species, or autologous transplantation, where the donor and recipient are the same individual.

In heterologous transplantation, the immune systems of the donor and recipient are significantly different, which can lead to a strong immune response against the transplanted organ or tissue. This is known as a graft-versus-host disease (GVHD), where the immune cells in the transplanted tissue attack the recipient's body.

Heterologous transplantation is not commonly performed in clinical medicine due to the high risk of rejection and GVHD. However, it may be used in research settings to study the biology of transplantation and to develop new therapies for transplant rejection.

Hepatitis B virus (HBV) is a DNA virus that belongs to the Hepadnaviridae family and causes the infectious disease known as hepatitis B. This virus primarily targets the liver, where it can lead to inflammation and damage of the liver tissue. The infection can range from acute to chronic, with chronic hepatitis B increasing the risk of developing serious liver complications such as cirrhosis and liver cancer.

The Hepatitis B virus has a complex life cycle, involving both nuclear and cytoplasmic phases. It enters hepatocytes (liver cells) via binding to specific receptors and is taken up by endocytosis. The viral DNA is released into the nucleus, where it is converted into a covalently closed circular DNA (cccDNA) form, which serves as the template for viral transcription.

HBV transcribes several RNAs, including pregenomic RNA (pgRNA), which is used as a template for reverse transcription during virion assembly. The pgRNA is encapsidated into core particles along with the viral polymerase and undergoes reverse transcription to generate new viral DNA. This process occurs within the cytoplasm of the hepatocyte, resulting in the formation of immature virions containing partially double-stranded DNA.

These immature virions are then enveloped by host cell membranes containing HBV envelope proteins (known as surface antigens) to form mature virions that can be secreted from the hepatocyte and infect other cells. The virus can also integrate into the host genome, which may contribute to the development of hepatocellular carcinoma in chronic cases.

Hepatitis B is primarily transmitted through exposure to infected blood or bodily fluids containing the virus, such as through sexual contact, sharing needles, or from mother to child during childbirth. Prevention strategies include vaccination, safe sex practices, and avoiding needle-sharing behaviors. Treatment for hepatitis B typically involves antiviral medications that can help suppress viral replication and reduce the risk of liver damage.

Hepatitis B e antigen (HBeAg) is a protein produced by the hepatitis B virus (HBV) during its replication process. It can be found in the blood of individuals infected with HBV. The presence of HBeAg generally indicates that the virus is actively replicating in the liver and that the individual has high levels of viral load.

HBeAg is a serological marker used to assess the severity and activity of HBV infection, as well as the response to antiviral treatment. In particular, the disappearance of HBeAg from the blood (known as seroconversion) is often associated with a decrease in viral replication and an improvement in liver disease. However, the presence of HBeAg does not necessarily mean that the individual will develop symptoms or liver damage, as some people can remain asymptomatic carriers of the virus for many years.

It's important to note that not all HBV strains produce HBeAg, and some mutant strains may not produce detectable levels of this antigen even when the virus is actively replicating. Therefore, additional tests may be needed to confirm the presence or absence of HBV infection in these cases.

"Plant proteins" refer to the proteins that are derived from plant sources. These can include proteins from legumes such as beans, lentils, and peas, as well as proteins from grains like wheat, rice, and corn. Other sources of plant proteins include nuts, seeds, and vegetables.

Plant proteins are made up of individual amino acids, which are the building blocks of protein. While animal-based proteins typically contain all of the essential amino acids that the body needs to function properly, many plant-based proteins may be lacking in one or more of these essential amino acids. However, by consuming a variety of plant-based foods throughout the day, it is possible to get all of the essential amino acids that the body needs from plant sources alone.

Plant proteins are often lower in calories and saturated fat than animal proteins, making them a popular choice for those following a vegetarian or vegan diet, as well as those looking to maintain a healthy weight or reduce their risk of chronic diseases such as heart disease and cancer. Additionally, plant proteins have been shown to have a number of health benefits, including improving gut health, reducing inflammation, and supporting muscle growth and repair.

Desiccation is a medical term that refers to the process of extreme dryness or the state of being dried up. It is the removal of water or moisture from an object or tissue, which can lead to its dehydration and preservation. In medicine, desiccation may be used as a therapeutic technique for treating certain conditions, such as drying out wet wounds or preventing infection in surgical instruments. However, desiccation can also have harmful effects on living tissues, leading to cell damage or death.

In a broader context, desiccation is also used to describe the process of drying up of an organ, tissue, or body part due to various reasons such as exposure to air, heat, or certain medical conditions that affect moisture regulation in the body. For example, diabetic patients may experience desiccation of their skin due to decreased moisture production and increased evaporation caused by high blood sugar levels. Similarly, people living in dry climates or using central heating systems may experience desiccation of their mucous membranes, leading to dryness of the eyes, nose, and throat.

A plant root is not a medical term per se, but it is a term from botany, which is the study of plants. However, I can certainly provide a definition for you.

Plant roots are the underground organs of a plant that typically grow downward into the soil. They serve several important functions, including:

1. Anchorage: Roots help to stabilize the plant and keep it upright in the ground.
2. Absorption: Roots absorb water and nutrients from the soil, which are essential for the plant's growth and development.
3. Conduction: Roots conduct water and nutrients up to the above-ground parts of the plant, such as the stem and leaves.
4. Vegetative reproduction: Some plants can reproduce vegetatively through their roots, producing new plants from root fragments or specialized structures called rhizomes or tubers.

Roots are composed of several different tissues, including the epidermis, cortex, endodermis, and vascular tissue. The epidermis is the outermost layer of the root, which secretes a waxy substance called suberin that helps to prevent water loss. The cortex is the middle layer of the root, which contains cells that store carbohydrates and other nutrients. The endodermis is a thin layer of cells that surrounds the vascular tissue and regulates the movement of water and solutes into and out of the root. The vascular tissue consists of xylem and phloem, which transport water and nutrients throughout the plant.

Monocytes are a type of white blood cell that are part of the immune system. They are large cells with a round or oval shape and a nucleus that is typically indented or horseshoe-shaped. Monocytes are produced in the bone marrow and then circulate in the bloodstream, where they can differentiate into other types of immune cells such as macrophages and dendritic cells.

Monocytes play an important role in the body's defense against infection and tissue damage. They are able to engulf and digest foreign particles, microorganisms, and dead or damaged cells, which helps to clear them from the body. Monocytes also produce cytokines, which are signaling molecules that help to coordinate the immune response.

Elevated levels of monocytes in the bloodstream can be a sign of an ongoing infection, inflammation, or other medical conditions such as cancer or autoimmune disorders.

A hapten is a small molecule that can elicit an immune response only when it is attached to a larger carrier protein. On its own, a hapten is too small to be recognized by the immune system as a foreign substance. However, when it binds to a carrier protein, it creates a new antigenic site that can be detected by the immune system. This process is known as haptenization.

Haptens are important in the study of immunology and allergies because they can cause an allergic response when they bind to proteins in the body. For example, certain chemicals found in cosmetics, drugs, or industrial products can act as haptens and trigger an allergic reaction when they come into contact with the skin or mucous membranes. The resulting immune response can cause symptoms such as rash, itching, or inflammation.

Haptens can also be used in the development of vaccines and diagnostic tests, where they are attached to carrier proteins to stimulate an immune response and produce specific antibodies that can be measured or used for therapy.

Toll-Like Receptor 4 (TLR4) is a type of protein found on the surface of some cells in the human body, including immune cells like macrophages and dendritic cells. It belongs to a class of proteins called pattern recognition receptors (PRRs), which play a crucial role in the innate immune system's response to infection.

TLR4 recognizes and responds to specific molecules found on gram-negative bacteria, such as lipopolysaccharide (LPS), also known as endotoxin. When TLR4 binds to LPS, it triggers a signaling cascade that leads to the activation of immune cells, production of pro-inflammatory cytokines and chemokines, and initiation of the adaptive immune response.

TLR4 is an essential component of the body's defense against gram-negative bacterial infections, but its overactivation can also contribute to the development of various inflammatory diseases, such as sepsis, atherosclerosis, and certain types of cancer.

'Arabidopsis' is a genus of small flowering plants that are part of the mustard family (Brassicaceae). The most commonly studied species within this genus is 'Arabidopsis thaliana', which is often used as a model organism in plant biology and genetics research. This plant is native to Eurasia and Africa, and it has a small genome that has been fully sequenced. It is known for its short life cycle, self-fertilization, and ease of growth, making it an ideal subject for studying various aspects of plant biology, including development, metabolism, and response to environmental stresses.

Glucose is a simple monosaccharide (or single sugar) that serves as the primary source of energy for living organisms. It's a fundamental molecule in biology, often referred to as "dextrose" or "grape sugar." Glucose has the molecular formula C6H12O6 and is vital to the functioning of cells, especially those in the brain and nervous system.

In the body, glucose is derived from the digestion of carbohydrates in food, and it's transported around the body via the bloodstream to cells where it can be used for energy. Cells convert glucose into a usable form through a process called cellular respiration, which involves a series of metabolic reactions that generate adenosine triphosphate (ATP)—the main currency of energy in cells.

Glucose is also stored in the liver and muscles as glycogen, a polysaccharide (multiple sugar) that can be broken down back into glucose when needed for energy between meals or during physical activity. Maintaining appropriate blood glucose levels is crucial for overall health, and imbalances can lead to conditions such as diabetes mellitus.

Species specificity is a term used in the field of biology, including medicine, to refer to the characteristic of a biological entity (such as a virus, bacterium, or other microorganism) that allows it to interact exclusively or preferentially with a particular species. This means that the biological entity has a strong affinity for, or is only able to infect, a specific host species.

For example, HIV is specifically adapted to infect human cells and does not typically infect other animal species. Similarly, some bacterial toxins are species-specific and can only affect certain types of animals or humans. This concept is important in understanding the transmission dynamics and host range of various pathogens, as well as in developing targeted therapies and vaccines.

Active immunity is a type of immunity that occurs when the body's own immune system produces a response to an antigen. This can happen in two ways: naturally or artificially.

Natural active immunity occurs when a person is exposed to a pathogen, such as a virus or bacteria, and their immune system mounts a response to fight off the infection. As part of this response, the immune system produces specific proteins called antibodies that recognize and bind to the antigen, neutralizing it and preventing future infections by the same pathogen. This type of immunity can last for years or even a lifetime, as memory cells are created that remain on alert for future encounters with the same antigen.

Artificial active immunity, also known as vaccination, involves introducing a weakened or killed form of a pathogen into the body, or pieces of the pathogen such as proteins or sugars, to stimulate an immune response. This triggers the production of antibodies and the creation of memory cells, providing protection against future infections by the same pathogen. Vaccines are a safe and effective way to induce active immunity and prevent the spread of infectious diseases.

Interleukin-12 (IL-12) is a naturally occurring protein that is primarily produced by activated macrophages and dendritic cells, which are types of immune cells. It plays a crucial role in the regulation of the immune response, particularly in the development of cell-mediated immunity.

IL-12 is composed of two subunits, p35 and p40, which combine to form a heterodimer. This cytokine stimulates the differentiation and activation of naive T cells into Th1 cells, which are important for fighting intracellular pathogens such as viruses and bacteria. IL-12 also enhances the cytotoxic activity of natural killer (NK) cells and CD8+ T cells, which can directly kill infected or malignant cells.

In addition to its role in the immune response, IL-12 has been implicated in the pathogenesis of several autoimmune diseases, including multiple sclerosis, rheumatoid arthritis, and psoriasis. As a result, therapeutic strategies targeting IL-12 or its signaling pathways have been explored as potential treatments for these conditions.

Antibody specificity refers to the ability of an antibody to bind to a specific epitope or antigenic determinant on an antigen. Each antibody has a unique structure that allows it to recognize and bind to a specific region of an antigen, typically a small portion of the antigen's surface made up of amino acids or sugar residues. This highly specific binding is mediated by the variable regions of the antibody's heavy and light chains, which form a pocket that recognizes and binds to the epitope.

The specificity of an antibody is determined by its unique complementarity-determining regions (CDRs), which are loops of amino acids located in the variable domains of both the heavy and light chains. The CDRs form a binding site that recognizes and interacts with the epitope on the antigen. The precise fit between the antibody's binding site and the epitope is critical for specificity, as even small changes in the structure of either can prevent binding.

Antibody specificity is important in immune responses because it allows the immune system to distinguish between self and non-self antigens. This helps to prevent autoimmune reactions where the immune system attacks the body's own cells and tissues. Antibody specificity also plays a crucial role in diagnostic tests, such as ELISA assays, where antibodies are used to detect the presence of specific antigens in biological samples.

Kidney transplantation is a surgical procedure where a healthy kidney from a deceased or living donor is implanted into a patient with end-stage renal disease (ESRD) or permanent kidney failure. The new kidney takes over the functions of filtering waste and excess fluids from the blood, producing urine, and maintaining the body's electrolyte balance.

The transplanted kidney is typically placed in the lower abdomen, with its blood vessels connected to the recipient's iliac artery and vein. The ureter of the new kidney is then attached to the recipient's bladder to ensure proper urine flow. Following the surgery, the patient will require lifelong immunosuppressive therapy to prevent rejection of the transplanted organ by their immune system.

A prediabetic state, also known as impaired glucose tolerance or prediabetes, is a metabolic condition where blood sugar levels are higher than normal but not high enough to meet the diagnostic criteria for diabetes. It is often characterized by insulin resistance and beta-cell dysfunction, which can lead to an increased risk of developing type 2 diabetes, cardiovascular disease, and other complications if left untreated.

In the prediabetic state, fasting plasma glucose levels are between 100 and 125 mg/dL (5.6-6.9 mmol/L), or hemoglobin A1c (HbA1c) levels are between 5.7% and 6.4%. Lifestyle modifications, such as regular exercise, healthy eating habits, and weight loss, can help prevent or delay the progression of prediabetes to diabetes.

Bacterial antigens are substances found on the surface or produced by bacteria that can stimulate an immune response in a host organism. These antigens can be proteins, polysaccharides, teichoic acids, lipopolysaccharides, or other molecules that are recognized as foreign by the host's immune system.

When a bacterial antigen is encountered by the host's immune system, it triggers a series of responses aimed at eliminating the bacteria and preventing infection. The host's immune system recognizes the antigen as foreign through the use of specialized receptors called pattern recognition receptors (PRRs), which are found on various immune cells such as macrophages, dendritic cells, and neutrophils.

Once a bacterial antigen is recognized by the host's immune system, it can stimulate both the innate and adaptive immune responses. The innate immune response involves the activation of inflammatory pathways, the recruitment of immune cells to the site of infection, and the production of antimicrobial peptides.

The adaptive immune response, on the other hand, involves the activation of T cells and B cells, which are specific to the bacterial antigen. These cells can recognize and remember the antigen, allowing for a more rapid and effective response upon subsequent exposures.

Bacterial antigens are important in the development of vaccines, as they can be used to stimulate an immune response without causing disease. By identifying specific bacterial antigens that are associated with virulence or pathogenicity, researchers can develop vaccines that target these antigens and provide protection against infection.

Diabetes Mellitus, Type 2 is a metabolic disorder characterized by high blood glucose (or sugar) levels resulting from the body's inability to produce sufficient amounts of insulin or effectively use the insulin it produces. This form of diabetes usually develops gradually over several years and is often associated with older age, obesity, physical inactivity, family history of diabetes, and certain ethnicities.

In Type 2 diabetes, the body's cells become resistant to insulin, meaning they don't respond properly to the hormone. As a result, the pancreas produces more insulin to help glucose enter the cells. Over time, the pancreas can't keep up with the increased demand, leading to high blood glucose levels and diabetes.

Type 2 diabetes is managed through lifestyle modifications such as weight loss, regular exercise, and a healthy diet. Medications, including insulin therapy, may also be necessary to control blood glucose levels and prevent long-term complications associated with the disease, such as heart disease, nerve damage, kidney damage, and vision loss.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

A lung is a pair of spongy, elastic organs in the chest that work together to enable breathing. They are responsible for taking in oxygen and expelling carbon dioxide through the process of respiration. The left lung has two lobes, while the right lung has three lobes. The lungs are protected by the ribcage and are covered by a double-layered membrane called the pleura. The trachea divides into two bronchi, which further divide into smaller bronchioles, leading to millions of tiny air sacs called alveoli, where the exchange of gases occurs.

Transfection is a term used in molecular biology that refers to the process of deliberately introducing foreign genetic material (DNA, RNA or artificial gene constructs) into cells. This is typically done using chemical or physical methods, such as lipofection or electroporation. Transfection is widely used in research and medical settings for various purposes, including studying gene function, producing proteins, developing gene therapies, and creating genetically modified organisms. It's important to note that transfection is different from transduction, which is the process of introducing genetic material into cells using viruses as vectors.

Chronic Hepatitis B is a persistent infection of the liver caused by the hepatitis B virus (HBV), which can lead to chronic inflammation and scarring of the liver over time. It is defined as the presence of hepatitis B surface antigen (HBsAg) in the blood for more than six months.

The infection can be asymptomatic or may cause nonspecific symptoms such as fatigue, loss of appetite, nausea, and joint pain. A small percentage of people with chronic HBV infection may develop serious complications, including cirrhosis, liver failure, and liver cancer. Treatment options for chronic hepatitis B include antiviral medications that can help to suppress the virus and reduce the risk of liver damage. Vaccination is available to prevent hepatitis B infection.

Bacterial proteins are a type of protein that are produced by bacteria as part of their structural or functional components. These proteins can be involved in various cellular processes, such as metabolism, DNA replication, transcription, and translation. They can also play a role in bacterial pathogenesis, helping the bacteria to evade the host's immune system, acquire nutrients, and multiply within the host.

Bacterial proteins can be classified into different categories based on their function, such as:

1. Enzymes: Proteins that catalyze chemical reactions in the bacterial cell.
2. Structural proteins: Proteins that provide structural support and maintain the shape of the bacterial cell.
3. Signaling proteins: Proteins that help bacteria to communicate with each other and coordinate their behavior.
4. Transport proteins: Proteins that facilitate the movement of molecules across the bacterial cell membrane.
5. Toxins: Proteins that are produced by pathogenic bacteria to damage host cells and promote infection.
6. Surface proteins: Proteins that are located on the surface of the bacterial cell and interact with the environment or host cells.

Understanding the structure and function of bacterial proteins is important for developing new antibiotics, vaccines, and other therapeutic strategies to combat bacterial infections.

Gamma-globulins are a type of protein found in the blood serum, specifically a class of immunoglobulins (antibodies) known as IgG. They are the most abundant type of antibody and provide long-term defense against bacterial and viral infections. Gamma-globulins can also be referred to as "gamma globulin" or "gamma immune globulins."

These proteins are produced by B cells, a type of white blood cell, in response to an antigen (a foreign substance that triggers an immune response). IgG gamma-globulins have the ability to cross the placenta and provide passive immunity to the fetus. They can be measured through various medical tests such as serum protein electrophoresis (SPEP) or immunoelectrophoresis, which are used to diagnose and monitor conditions related to immune system disorders, such as multiple myeloma or primary immunodeficiency diseases.

In addition, gamma-globulins can be administered therapeutically in the form of intravenous immunoglobulin (IVIG) to provide passive immunity for patients with immunodeficiencies, autoimmune disorders, or infectious diseases.

Intranasal administration refers to the delivery of medication or other substances through the nasal passages and into the nasal cavity. This route of administration can be used for systemic absorption of drugs or for localized effects in the nasal area.

When a medication is administered intranasally, it is typically sprayed or dropped into the nostril, where it is absorbed by the mucous membranes lining the nasal cavity. The medication can then pass into the bloodstream and be distributed throughout the body for systemic effects. Intranasal administration can also result in direct absorption of the medication into the local tissues of the nasal cavity, which can be useful for treating conditions such as allergies, migraines, or pain in the nasal area.

Intranasal administration has several advantages over other routes of administration. It is non-invasive and does not require needles or injections, making it a more comfortable option for many people. Additionally, intranasal administration can result in faster onset of action than oral administration, as the medication bypasses the digestive system and is absorbed directly into the bloodstream. However, there are also some limitations to this route of administration, including potential issues with dosing accuracy and patient tolerance.

Asthma is a chronic respiratory disease characterized by inflammation and narrowing of the airways, leading to symptoms such as wheezing, coughing, shortness of breath, and chest tightness. The airway obstruction in asthma is usually reversible, either spontaneously or with treatment.

The underlying cause of asthma involves a combination of genetic and environmental factors that result in hypersensitivity of the airways to certain triggers, such as allergens, irritants, viruses, exercise, and emotional stress. When these triggers are encountered, the airways constrict due to smooth muscle spasm, swell due to inflammation, and produce excess mucus, leading to the characteristic symptoms of asthma.

Asthma is typically managed with a combination of medications that include bronchodilators to relax the airway muscles, corticosteroids to reduce inflammation, and leukotriene modifiers or mast cell stabilizers to prevent allergic reactions. Avoiding triggers and monitoring symptoms are also important components of asthma management.

There are several types of asthma, including allergic asthma, non-allergic asthma, exercise-induced asthma, occupational asthma, and nocturnal asthma, each with its own set of triggers and treatment approaches. Proper diagnosis and management of asthma can help prevent exacerbations, improve quality of life, and reduce the risk of long-term complications.

Toll-like receptor 2 (TLR2) is a type of protein belonging to the family of pattern recognition receptors (PRRs), which play a crucial role in the innate immune system's response to pathogens. TLR2 is primarily expressed on the surface of various immune cells, including monocytes, macrophages, dendritic cells, and B cells.

TLR2 recognizes a wide range of microbial components, such as lipopeptides, lipoteichoic acid, and zymosan, derived from both gram-positive and gram-negative bacteria, fungi, and certain viruses. Upon recognition and binding to these ligands, TLR2 initiates a signaling cascade that activates various transcription factors, leading to the production of proinflammatory cytokines, chemokines, and costimulatory molecules. This response is essential for the activation and recruitment of immune cells to the site of infection, thereby contributing to the clearance of invading pathogens.

In summary, TLR2 is a vital pattern recognition receptor that helps the innate immune system detect and respond to various microbial threats by initiating an inflammatory response upon ligand binding.

"Oryza sativa" is the scientific name for Asian rice, which is a species of grass and one of the most important food crops in the world. It is a staple food for more than half of the global population, providing a significant source of calories and carbohydrates. There are several varieties of Oryza sativa, including indica and japonica, which differ in their genetic makeup, growth habits, and grain characteristics.

Oryza sativa is an annual plant that grows to a height of 1-2 meters and produces long slender leaves and clusters of flowers at the top of the stem. The grains are enclosed within a tough husk, which must be removed before consumption. Rice is typically grown in flooded fields or paddies, which provide the necessary moisture for germination and growth.

Rice is an important source of nutrition for people around the world, particularly in developing countries where it may be one of the few reliable sources of food. It is rich in carbohydrates, fiber, and various vitamins and minerals, including thiamin, riboflavin, niacin, iron, and magnesium. However, rice can also be a significant source of arsenic, a toxic heavy metal that can accumulate in the grain during growth.

In medical terms, Oryza sativa may be used as a component of nutritional interventions for individuals who are at risk of malnutrition or who have specific dietary needs. It may also be studied in clinical trials to evaluate its potential health benefits or risks.

I believe there may be a slight misunderstanding in your question. "Plant leaves" are not a medical term, but rather a general biological term referring to a specific organ found in plants.

Leaves are organs that are typically flat and broad, and they are the primary site of photosynthesis in most plants. They are usually green due to the presence of chlorophyll, which is essential for capturing sunlight and converting it into chemical energy through photosynthesis.

While leaves do not have a direct medical definition, understanding their structure and function can be important in various medical fields, such as pharmacognosy (the study of medicinal plants) or environmental health. For example, certain plant leaves may contain bioactive compounds that have therapeutic potential, while others may produce allergens or toxins that can impact human health.

In a medical context, "hot temperature" is not a standard medical term with a specific definition. However, it is often used in relation to fever, which is a common symptom of illness. A fever is typically defined as a body temperature that is higher than normal, usually above 38°C (100.4°F) for adults and above 37.5-38°C (99.5-101.3°F) for children, depending on the source.

Therefore, when a medical professional talks about "hot temperature," they may be referring to a body temperature that is higher than normal due to fever or other causes. It's important to note that a high environmental temperature can also contribute to an elevated body temperature, so it's essential to consider both the body temperature and the environmental temperature when assessing a patient's condition.

Hematopoietic Stem Cell Transplantation (HSCT) is a medical procedure where hematopoietic stem cells (immature cells that give rise to all blood cell types) are transplanted into a patient. This procedure is often used to treat various malignant and non-malignant disorders affecting the hematopoietic system, such as leukemias, lymphomas, multiple myeloma, aplastic anemia, inherited immune deficiency diseases, and certain genetic metabolic disorders.

The transplantation can be autologous (using the patient's own stem cells), allogeneic (using stem cells from a genetically matched donor, usually a sibling or unrelated volunteer), or syngeneic (using stem cells from an identical twin).

The process involves collecting hematopoietic stem cells, most commonly from the peripheral blood or bone marrow. The collected cells are then infused into the patient after the recipient's own hematopoietic system has been ablated (or destroyed) using high-dose chemotherapy and/or radiation therapy. This allows the donor's stem cells to engraft, reconstitute, and restore the patient's hematopoietic system.

HSCT is a complex and potentially risky procedure with various complications, including graft-versus-host disease, infections, and organ damage. However, it offers the potential for cure or long-term remission in many patients with otherwise fatal diseases.

The uterus, also known as the womb, is a hollow, muscular organ located in the female pelvic cavity, between the bladder and the rectum. It has a thick, middle layer called the myometrium, which is composed of smooth muscle tissue, and an inner lining called the endometrium, which provides a nurturing environment for the fertilized egg to develop into a fetus during pregnancy.

The uterus is where the baby grows and develops until it is ready for birth through the cervix, which is the lower, narrow part of the uterus that opens into the vagina. The uterus plays a critical role in the menstrual cycle as well, by shedding its lining each month if pregnancy does not occur.

Immune Reconstitution Inflammatory Syndrome (IRIS) is not a disease itself, but rather a reaction that can occur in some individuals who have a weakened immune system and then receive treatment to restore their immune function.

IRIS is defined as a paradoxical clinical worsening or appearance of new symptoms following the initiation of antiretroviral therapy (ART) in HIV-infected patients, or after the administration of other immunomodulatory agents in patients with other types of immune deficiency.

This reaction is thought to be due to an overactive immune response to opportunistic infections or malignancies that were present but not causing symptoms while the patient's immune system was severely compromised. As the immune system begins to recover, it may mount a strong inflammatory response to these underlying infections or cancers, leading to worsening of symptoms or the development of new ones.

IRIS can affect various organs and systems, causing a wide range of clinical manifestations. The most common opportunistic infections associated with IRIS include Mycobacterium avium complex (MAC), Cytomegalovirus (CMV), Pneumocystis jirovecii pneumonia (PJP), and Cryptococcus neoformans.

The management of IRIS involves a careful balance between continuing the immune-restoring therapy and providing appropriate treatment for the underlying infection or malignancy, while also managing the inflammatory response with anti-inflammatory medications if necessary.

The complement system is a group of proteins found in the blood and on the surface of cells that when activated, work together to help eliminate pathogens such as bacteria, viruses, and fungi from the body. The proteins are normally inactive in the bloodstream. When they encounter an invading microorganism or foreign substance, a series of reactions take place leading to the activation of the complement system. Activation results in the production of effector molecules that can punch holes in the cell membranes of pathogens, recruit and activate immune cells, and help remove debris and dead cells from the body.

There are three main pathways that can lead to complement activation: the classical pathway, the lectin pathway, and the alternative pathway. Each pathway involves a series of proteins that work together in a cascade-like manner to amplify the response and generate effector molecules. The three main effector molecules produced by the complement system are C3b, C4b, and C5b. These molecules can bind to the surface of pathogens, marking them for destruction by other immune cells.

Complement proteins also play a role in the regulation of the immune response. They help to prevent excessive activation of the complement system, which could damage host tissues. Dysregulation of the complement system has been implicated in a number of diseases, including autoimmune disorders and inflammatory conditions.

In summary, Complement System Proteins are a group of proteins that play a crucial role in the immune response by helping to eliminate pathogens and regulate the immune response. They can be activated through three different pathways, leading to the production of effector molecules that mark pathogens for destruction. Dysregulation of the complement system has been linked to various diseases.

A vaccine is a biological preparation that provides active acquired immunity to a particular infectious disease. It typically contains an agent that resembles the disease-causing microorganism and is often made from weakened or killed forms of the microbe, its toxins, or one of its surface proteins. The agent stimulates the body's immune system to recognize the agent as a threat, destroy it, and "remember" it, so that the immune system can more easily recognize and destroy any of these microorganisms that it encounters in the future.

Vaccines can be prophylactic (to prevent or ameliorate the effects of a future infection by a natural or "wild" pathogen), or therapeutic (to fight disease that is already present). The administration of vaccines is called vaccination. Vaccinations are generally administered through needle injections, but can also be administered by mouth or sprayed into the nose.

The term "vaccine" comes from Edward Jenner's 1796 use of cowpox to create immunity to smallpox. The first successful vaccine was developed in 1796 by Edward Jenner, who showed that milkmaids who had contracted cowpox did not get smallpox. He reasoned that exposure to cowpox protected against smallpox and tested his theory by injecting a boy with pus from a cowpox sore and then exposing him to smallpox, which the boy did not contract. The word "vaccine" is derived from Variolae vaccinae (smallpox of the cow), the term devised by Jenner to denote cowpox. He used it in 1798 during a conversation with a fellow physician and later in the title of his 1801 Inquiry.

The chemical element aluminum (or aluminium in British English) is a silvery-white, soft, non-magnetic, ductile metal. The atomic number of aluminum is 13 and its symbol on the periodic table is Al. It is the most abundant metallic element in the Earth's crust and is found in a variety of minerals such as bauxite.

Aluminum is resistant to corrosion due to the formation of a thin layer of aluminum oxide on its surface that protects it from further oxidation. It is lightweight, has good thermal and electrical conductivity, and can be easily formed and machined. These properties make aluminum a widely used metal in various industries such as construction, packaging, transportation, and electronics.

In the medical field, aluminum is used in some medications and medical devices. For example, aluminum hydroxide is commonly used as an antacid to neutralize stomach acid and treat heartburn, while aluminum salts are used as adjuvants in vaccines to enhance the immune response. However, excessive exposure to aluminum can be harmful and has been linked to neurological disorders such as Alzheimer's disease, although the exact relationship between aluminum and these conditions is not fully understood.

Leukocytes, also known as white blood cells (WBCs), are a crucial component of the human immune system. They are responsible for protecting the body against infections and foreign substances. Leukocytes are produced in the bone marrow and circulate throughout the body in the bloodstream and lymphatic system.

There are several types of leukocytes, including:

1. Neutrophils - These are the most abundant type of leukocyte and are primarily responsible for fighting bacterial infections. They contain enzymes that can destroy bacteria.
2. Lymphocytes - These are responsible for producing antibodies and destroying virus-infected cells, as well as cancer cells. There are two main types of lymphocytes: B-lymphocytes and T-lymphocytes.
3. Monocytes - These are the largest type of leukocyte and help to break down and remove dead or damaged tissues, as well as microorganisms.
4. Eosinophils - These play a role in fighting parasitic infections and are also involved in allergic reactions and inflammation.
5. Basophils - These release histamine and other chemicals that cause inflammation in response to allergens or irritants.

An abnormal increase or decrease in the number of leukocytes can indicate an underlying medical condition, such as an infection, inflammation, or a blood disorder.

Immunologic surveillance is the concept that the immune system plays a critical role in monitoring and defending the body against the development of malignancies or cancers. The immune cells, particularly T-cells and natural killer (NK) cells, are constantly scanning the body for any abnormal changes in cells, such as mutations or viral infections, that could lead to cancer.

Once these abnormal cells are detected, the immune system mounts an immune response to eliminate them, preventing their proliferation and progression into full-blown cancers. This process of immunologic surveillance is a critical component of the body's defense mechanisms against cancer and helps to maintain tissue homeostasis and prevent tumorigenesis.

However, in some cases, cancer cells may evade or suppress the immune system's surveillance mechanisms, leading to the development and progression of malignancies. Therefore, understanding the mechanisms of immunologic surveillance is crucial for developing novel cancer therapies that harness the power of the immune system to fight against cancer.

Interleukin-6 (IL-6) is a cytokine, a type of protein that plays a crucial role in communication between cells, especially in the immune system. It is produced by various cells including T-cells, B-cells, fibroblasts, and endothelial cells in response to infection, injury, or inflammation.

IL-6 has diverse effects on different cell types. In the immune system, it stimulates the growth and differentiation of B-cells into plasma cells that produce antibodies. It also promotes the activation and survival of T-cells. Moreover, IL-6 plays a role in fever induction by acting on the hypothalamus to raise body temperature during an immune response.

In addition to its functions in the immune system, IL-6 has been implicated in various physiological processes such as hematopoiesis (the formation of blood cells), bone metabolism, and neural development. However, abnormal levels of IL-6 have also been associated with several diseases, including autoimmune disorders, chronic inflammation, and cancer.

Morphine dependence is a medical condition characterized by a physical and psychological dependency on morphine, a potent opioid analgesic. This dependence develops as a result of repeated use or abuse of morphine, leading to changes in the brain's reward and pleasure pathways. The Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) outlines the following criteria for diagnosing opioid dependence, which includes morphine:

A. A problematic pattern of opioid use leading to clinically significant impairment or distress, as manifested by at least two of the following, occurring within a 12-month period:

1. Opioids are often taken in larger amounts or over a longer period than was intended.
2. There is a persistent desire or unsuccessful efforts to cut down or control opioid use.
3. A great deal of time is spent in activities necessary to obtain the opioid, use the opioid, or recover from its effects.
4. Craving, or a strong desire or urge to use opioids.
5. Recurrent opioid use resulting in a failure to fulfill major role obligations at work, school, or home.
6. Continued opioid use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of opioids.
7. Important social, occupational, or recreational activities are given up or reduced because of opioid use.
8. Recurrent opioid use in situations in which it is physically hazardous.
9. Continued opioid use despite knowing that a physical or psychological problem is likely to have been caused or exacerbated by opioids.
10. Tolerance, as defined by either of the following:
a. A need for markedly increased amounts of opioids to achieve intoxication or desired effect.
b. A markedly diminished effect with continued use of the same amount of an opioid.
11. Withdrawal, as manifested by either of the following:
a. The characteristic opioid withdrawal syndrome.
b. The same (or a closely related) substance is taken to relieve or avoid withdrawal symptoms.

Additionally, it's important to note that if someone has been using opioids for an extended period and suddenly stops taking them, they may experience withdrawal symptoms. These can include:

- Anxiety
- Muscle aches
- Insomnia
- Runny nose
- Sweating
- Diarrhea
- Nausea or vomiting
- Abdominal cramping
- Dilated pupils

If you or someone you know is struggling with opioid use, it's essential to seek professional help. There are many resources available, including inpatient and outpatient treatment programs, support groups, and medications that can help manage withdrawal symptoms and cravings.

Nitroglycerin, also known as glyceryl trinitrate, is a medication used primarily for the treatment of angina pectoris (chest pain due to coronary artery disease) and hypertensive emergencies (severe high blood pressure). It belongs to a class of drugs called nitrates or organic nitrites.

Nitroglycerin works by relaxing and dilating the smooth muscle in blood vessels, which leads to decreased workload on the heart and increased oxygen delivery to the myocardium (heart muscle). This results in reduced symptoms of angina and improved cardiac function during hypertensive emergencies.

The drug is available in various forms, including sublingual tablets, sprays, transdermal patches, ointments, and intravenous solutions. The choice of formulation depends on the specific clinical situation and patient needs. Common side effects of nitroglycerin include headache, dizziness, and hypotension (low blood pressure).

Ischemic preconditioning is a phenomenon in which brief, non-lethal episodes of ischemia (restriction or interruption of blood supply to an organ or tissue) render the tissue more resistant to subsequent prolonged ischemia and reperfusion injury. This adaptive response involves a complex series of cellular and molecular changes that protect the myocardium, brain, kidney, or other organs from ischemic damage. The underlying mechanisms include the activation of various signaling pathways, such as adenosine, opioid, and kinase pathways, which lead to the production of protective factors and the modulation of cellular responses to ischemia and reperfusion injury. Ischemic preconditioning has been extensively studied in the context of cardiovascular medicine, where it has been shown to reduce infarct size and improve cardiac function after myocardial infarction. However, this protective phenomenon has also been observed in other organs and systems, including the brain, kidney, liver, and skeletal muscle.

The lactose tolerance test is a medical procedure used to determine the body's ability to digest lactose, a sugar found in milk and other dairy products. In this test, a patient is given a liquid that contains a high amount of lactose to drink. Blood samples are then taken over a two-hour period following the consumption of the lactose solution. These blood samples are tested for glucose levels.

If the body is able to digest lactose properly, the lactose will be broken down into glucose and absorbed into the bloodstream, resulting in an increase in blood glucose levels. However, if the body has difficulty digesting lactose (lactose intolerance), little or no increase in blood glucose levels will be observed.

A positive lactose tolerance test indicates that the individual can tolerate lactose and has a functioning lactase enzyme in their small intestine. A negative result suggests lactose intolerance, which is often due to insufficient lactase production. This condition can lead to symptoms such as bloating, diarrhea, and abdominal cramps after consuming dairy products.

Inflammation mediators are substances that are released by the body in response to injury or infection, which contribute to the inflammatory response. These mediators include various chemical factors such as cytokines, chemokines, prostaglandins, leukotrienes, and histamine, among others. They play a crucial role in regulating the inflammatory process by attracting immune cells to the site of injury or infection, increasing blood flow to the area, and promoting the repair and healing of damaged tissues. However, an overactive or chronic inflammatory response can also contribute to the development of various diseases and conditions, such as autoimmune disorders, cardiovascular disease, and cancer.

Lymphocyte subsets refer to distinct populations of white blood cells called lymphocytes, which are crucial components of the adaptive immune system. There are two main types of lymphocytes: T cells and B cells, and each type has several subsets based on their surface receptors, functions, and activation status.

1. T cell subsets: These include CD4+ T helper cells (Th cells), CD8+ cytotoxic T cells (Tc cells), regulatory T cells (Tregs), and memory T cells. Th cells are further divided into Th1, Th2, Th17, and Tfh cells based on their cytokine production profiles and functions.
* CD4+ T helper cells (Th cells) play a central role in orchestrating the immune response by producing various cytokines that activate other immune cells.
* CD8+ cytotoxic T cells (Tc cells) directly kill virus-infected or malignant cells upon recognition of specific antigens presented on their surface.
* Regulatory T cells (Tregs) suppress the activation and proliferation of other immune cells to maintain self-tolerance and prevent autoimmunity.
* Memory T cells are long-lived cells that remain in the body after an initial infection or immunization, providing rapid protection upon subsequent encounters with the same pathogen.
2. B cell subsets: These include naïve B cells, memory B cells, and plasma cells. Upon activation by antigens, B cells differentiate into antibody-secreting plasma cells that produce specific antibodies to neutralize or eliminate pathogens.
* Naïve B cells are resting cells that have not yet encountered their specific antigen.
* Memory B cells are long-lived cells generated after initial antigen exposure, which can quickly differentiate into antibody-secreting plasma cells upon re-exposure to the same antigen.
* Plasma cells are terminally differentiated B cells that secrete large amounts of specific antibodies.

Analyzing lymphocyte subsets is essential for understanding immune system function and dysfunction, as well as monitoring the effectiveness of immunotherapies and vaccinations.

Thymectomy is a surgical procedure that involves the removal of the thymus gland. The thymus gland is a part of the immune system located in the upper chest, behind the sternum (breastbone), and above the heart. It is responsible for producing white blood cells called T-lymphocytes, which help fight infections.

Thymectomy is often performed as a treatment option for patients with certain medical conditions, such as:

* Myasthenia gravis: an autoimmune disorder that causes muscle weakness and fatigue. In some cases, the thymus gland may contain abnormal cells that contribute to the development of myasthenia gravis. Removing the thymus gland can help improve symptoms in some patients with this condition.
* Thymomas: tumors that develop in the thymus gland. While most thymomas are benign (non-cancerous), some can be malignant (cancerous) and may require surgical removal.
* Myasthenic syndrome: a group of disorders characterized by muscle weakness and fatigue, similar to myasthenia gravis. In some cases, the thymus gland may be abnormal and contribute to the development of these conditions. Removing the thymus gland can help improve symptoms in some patients.

Thymectomy can be performed using various surgical approaches, including open surgery (through a large incision in the chest), video-assisted thoracoscopic surgery (VATS, using small incisions and a camera to guide the procedure), or robotic-assisted surgery (using a robot to perform the procedure through small incisions). The choice of surgical approach depends on several factors, including the size and location of the thymus gland, the patient's overall health, and the surgeon's expertise.

Subcutaneous injection is a route of administration where a medication or vaccine is delivered into the subcutaneous tissue, which lies between the skin and the muscle. This layer contains small blood vessels, nerves, and connective tissues that help to absorb the medication slowly and steadily over a period of time. Subcutaneous injections are typically administered using a short needle, at an angle of 45-90 degrees, and the dose is injected slowly to minimize discomfort and ensure proper absorption. Common sites for subcutaneous injections include the abdomen, thigh, or upper arm. Examples of medications that may be given via subcutaneous injection include insulin, heparin, and some vaccines.

Arabidopsis proteins refer to the proteins that are encoded by the genes in the Arabidopsis thaliana plant, which is a model organism commonly used in plant biology research. This small flowering plant has a compact genome and a short life cycle, making it an ideal subject for studying various biological processes in plants.

Arabidopsis proteins play crucial roles in many cellular functions, such as metabolism, signaling, regulation of gene expression, response to environmental stresses, and developmental processes. Research on Arabidopsis proteins has contributed significantly to our understanding of plant biology and has provided valuable insights into the molecular mechanisms underlying various agronomic traits.

Some examples of Arabidopsis proteins include transcription factors, kinases, phosphatases, receptors, enzymes, and structural proteins. These proteins can be studied using a variety of techniques, such as biochemical assays, protein-protein interaction studies, and genetic approaches, to understand their functions and regulatory mechanisms in plants.

Disease susceptibility, also known as genetic predisposition or genetic susceptibility, refers to the increased likelihood or risk of developing a particular disease due to inheriting specific genetic variations or mutations. These genetic factors can make an individual more vulnerable to certain diseases compared to those who do not have these genetic changes.

It is important to note that having a genetic predisposition does not guarantee that a person will definitely develop the disease. Other factors, such as environmental exposures, lifestyle choices, and additional genetic variations, can influence whether or not the disease will manifest. In some cases, early detection and intervention may help reduce the risk or delay the onset of the disease in individuals with a known genetic susceptibility.

Immunoglobulin E (IgE) is a type of antibody that plays a key role in the immune response to parasitic infections and allergies. It is produced by B cells in response to stimulation by antigens, such as pollen, pet dander, or certain foods. Once produced, IgE binds to receptors on the surface of mast cells and basophils, which are immune cells found in tissues and blood respectively. When an individual with IgE antibodies encounters the allergen again, the cross-linking of IgE molecules bound to the FcεRI receptor triggers the release of mediators such as histamine, leukotrienes, prostaglandins, and various cytokines from these cells. These mediators cause the symptoms of an allergic reaction, such as itching, swelling, and redness. IgE also plays a role in protecting against certain parasitic infections by activating eosinophils, which can kill the parasites.

In summary, Immunoglobulin E (IgE) is a type of antibody that plays a crucial role in the immune response to allergens and parasitic infections, it binds to receptors on the surface of mast cells and basophils, when an individual with IgE antibodies encounters the allergen again, it triggers the release of mediators from these cells causing the symptoms of an allergic reaction.

Opioid mu receptors, also known as mu-opioid receptors (MORs), are a type of G protein-coupled receptor that binds to opioids, a class of chemicals that include both natural and synthetic painkillers. These receptors are found in the brain, spinal cord, and gastrointestinal tract, and play a key role in mediating the effects of opioid drugs such as morphine, heroin, and oxycodone.

MORs are involved in pain modulation, reward processing, respiratory depression, and physical dependence. Activation of MORs can lead to feelings of euphoria, decreased perception of pain, and slowed breathing. Prolonged activation of these receptors can also result in tolerance, where higher doses of the drug are required to achieve the same effect, and dependence, where withdrawal symptoms occur when the drug is discontinued.

MORs have three main subtypes: MOR-1, MOR-2, and MOR-3, with MOR-1 being the most widely studied and clinically relevant. Selective agonists for MOR-1, such as fentanyl and sufentanil, are commonly used in anesthesia and pain management. However, the abuse potential and risk of overdose associated with these drugs make them a significant public health concern.

Fasting is defined in medical terms as the abstinence from food or drink for a period of time. This practice is often recommended before certain medical tests or procedures, as it helps to ensure that the results are not affected by recent eating or drinking.

In some cases, fasting may also be used as a therapeutic intervention, such as in the management of seizures or other neurological conditions. Fasting can help to lower blood sugar and insulin levels, which can have a variety of health benefits. However, it is important to note that prolonged fasting can also have negative effects on the body, including malnutrition, dehydration, and electrolyte imbalances.

Fasting is also a spiritual practice in many religions, including Christianity, Islam, Buddhism, and Hinduism. In these contexts, fasting is often seen as a way to purify the mind and body, to focus on spiritual practices, or to express devotion or mourning.

Antibody-producing cells, also known as plasma cells, are a type of white blood cell that is responsible for producing and secreting antibodies in response to a foreign substance or antigen. These cells are derived from B lymphocytes, which become activated upon encountering an antigen and differentiate into plasma cells.

Once activated, plasma cells can produce large amounts of specific antibodies that bind to the antigen, marking it for destruction by other immune cells. Antibody-producing cells play a crucial role in the body's humoral immune response, which helps protect against infection and disease.

Hemocyanin is a copper-containing protein found in the blood of some mollusks and arthropods, responsible for oxygen transport. Unlike hemoglobin in vertebrates, which uses iron to bind oxygen, hemocyanins have copper ions that reversibly bind to oxygen, turning the blood blue when oxygenated. When deoxygenated, the color of the blood is pale blue-gray. Hemocyanins are typically found in a multi-subunit form and are released into the hemolymph (the equivalent of blood in vertebrates) upon exposure to air or oxygen. They play a crucial role in supplying oxygen to various tissues and organs within these invertebrate organisms.

HIV (Human Immunodeficiency Virus) infection is a viral illness that progressively attacks and weakens the immune system, making individuals more susceptible to other infections and diseases. The virus primarily infects CD4+ T cells, a type of white blood cell essential for fighting off infections. Over time, as the number of these immune cells declines, the body becomes increasingly vulnerable to opportunistic infections and cancers.

HIV infection has three stages:

1. Acute HIV infection: This is the initial stage that occurs within 2-4 weeks after exposure to the virus. During this period, individuals may experience flu-like symptoms such as fever, fatigue, rash, swollen glands, and muscle aches. The virus replicates rapidly, and the viral load in the body is very high.
2. Chronic HIV infection (Clinical latency): This stage follows the acute infection and can last several years if left untreated. Although individuals may not show any symptoms during this phase, the virus continues to replicate at low levels, and the immune system gradually weakens. The viral load remains relatively stable, but the number of CD4+ T cells declines over time.
3. AIDS (Acquired Immunodeficiency Syndrome): This is the most advanced stage of HIV infection, characterized by a severely damaged immune system and numerous opportunistic infections or cancers. At this stage, the CD4+ T cell count drops below 200 cells/mm3 of blood.

It's important to note that with proper antiretroviral therapy (ART), individuals with HIV infection can effectively manage the virus, maintain a healthy immune system, and significantly reduce the risk of transmission to others. Early diagnosis and treatment are crucial for improving long-term health outcomes and reducing the spread of HIV.

Body weight is the measure of the force exerted on a scale or balance by an object's mass, most commonly expressed in units such as pounds (lb) or kilograms (kg). In the context of medical definitions, body weight typically refers to an individual's total weight, which includes their skeletal muscle, fat, organs, and bodily fluids.

Healthcare professionals often use body weight as a basic indicator of overall health status, as it can provide insights into various aspects of a person's health, such as nutritional status, metabolic function, and risk factors for certain diseases. For example, being significantly underweight or overweight can increase the risk of developing conditions like malnutrition, diabetes, heart disease, and certain types of cancer.

It is important to note that body weight alone may not provide a complete picture of an individual's health, as it does not account for factors such as muscle mass, bone density, or body composition. Therefore, healthcare professionals often use additional measures, such as body mass index (BMI), waist circumference, and blood tests, to assess overall health status more comprehensively.

Chemokines are a family of small cytokines, or signaling proteins, that are secreted by cells and play an important role in the immune system. They are chemotactic, meaning they can attract and guide the movement of various immune cells to specific locations within the body. Chemokines do this by binding to G protein-coupled receptors on the surface of target cells, initiating a signaling cascade that leads to cell migration.

There are four main subfamilies of chemokines, classified based on the arrangement of conserved cysteine residues near the amino terminus: CXC, CC, C, and CX3C. Different chemokines have specific roles in inflammation, immune surveillance, hematopoiesis, and development. Dysregulation of chemokine function has been implicated in various diseases, including autoimmune disorders, infections, and cancer.

In summary, Chemokines are a group of signaling proteins that play a crucial role in the immune system by directing the movement of immune cells to specific locations within the body, thus helping to coordinate the immune response.

A radiation chimera is not a widely used or recognized medical term. However, in the field of genetics and radiation biology, a "chimera" refers to an individual that contains cells with different genetic backgrounds. A radiation chimera, therefore, could refer to an organism that has become a chimera as a result of exposure to radiation, which can cause mutations and changes in the genetic makeup of cells.

Ionizing radiation, such as that used in cancer treatments or nuclear accidents, can cause DNA damage and mutations in cells. If an organism is exposed to radiation and some of its cells undergo mutations while others do not, this could result in a chimera with genetically distinct populations of cells.

However, it's important to note that the term "radiation chimera" is not commonly used in medical literature or clinical settings. If you encounter this term in a different context, I would recommend seeking clarification from the source to ensure a proper understanding.

Synthetic vaccines are artificially produced, designed to stimulate an immune response and provide protection against specific diseases. Unlike traditional vaccines that are derived from weakened or killed pathogens, synthetic vaccines are created using synthetic components, such as synthesized viral proteins, DNA, or RNA. These components mimic the disease-causing agent and trigger an immune response without causing the actual disease. The use of synthetic vaccines offers advantages in terms of safety, consistency, and scalability in production, making them valuable tools for preventing infectious diseases.

Immunocompetence is the condition of having a properly functioning immune system that can effectively respond to the presence of foreign substances, such as pathogens (like bacteria, viruses, and parasites) and other potentially harmful agents. It involves the ability of the immune system to recognize, attack, and eliminate these foreign substances while also maintaining tolerance to self-tissues and promoting tissue repair.

Immunocompetence is essential for overall health and wellbeing, as it helps protect the body from infections and diseases. Factors that can affect immunocompetence include age, genetics, stress, nutrition, sleep, and certain medical conditions or treatments (like chemotherapy or immunosuppressive drugs) that can weaken the immune system.

Neutrophils are a type of white blood cell that are part of the immune system's response to infection. They are produced in the bone marrow and released into the bloodstream where they circulate and are able to move quickly to sites of infection or inflammation in the body. Neutrophils are capable of engulfing and destroying bacteria, viruses, and other foreign substances through a process called phagocytosis. They are also involved in the release of inflammatory mediators, which can contribute to tissue damage in some cases. Neutrophils are characterized by the presence of granules in their cytoplasm, which contain enzymes and other proteins that help them carry out their immune functions.

Oligonucleotide Array Sequence Analysis is a type of microarray analysis that allows for the simultaneous measurement of the expression levels of thousands of genes in a single sample. In this technique, oligonucleotides (short DNA sequences) are attached to a solid support, such as a glass slide, in a specific pattern. These oligonucleotides are designed to be complementary to specific target mRNA sequences from the sample being analyzed.

During the analysis, labeled RNA or cDNA from the sample is hybridized to the oligonucleotide array. The level of hybridization is then measured and used to determine the relative abundance of each target sequence in the sample. This information can be used to identify differences in gene expression between samples, which can help researchers understand the underlying biological processes involved in various diseases or developmental stages.

It's important to note that this technique requires specialized equipment and bioinformatics tools for data analysis, as well as careful experimental design and validation to ensure accurate and reproducible results.

IgG receptors, also known as Fcγ receptors (Fc gamma receptors), are specialized protein molecules found on the surface of various immune cells, such as neutrophils, monocytes, macrophages, and some lymphocytes. These receptors recognize and bind to the Fc region of IgG antibodies, one of the five classes of immunoglobulins in the human body.

IgG receptors play a crucial role in immune responses by mediating different effector functions, including:

1. Antibody-dependent cellular cytotoxicity (ADCC): IgG receptors on natural killer (NK) cells and other immune cells bind to IgG antibodies coated on the surface of virus-infected or cancer cells, leading to their destruction.
2. Phagocytosis: When IgG antibodies tag pathogens or foreign particles, phagocytes like neutrophils and macrophages recognize and bind to these immune complexes via IgG receptors, facilitating the engulfment and removal of the targeted particles.
3. Antigen presentation: IgG receptors on antigen-presenting cells (APCs) can internalize immune complexes, process the antigens, and present them to T cells, thereby initiating adaptive immune responses.
4. Inflammatory response regulation: IgG receptors can modulate inflammation by activating or inhibiting downstream signaling pathways in immune cells, depending on the specific type of Fcγ receptor and its activation state.

There are several types of IgG receptors (FcγRI, FcγRII, FcγRIII, and FcγRIV) with varying affinities for different subclasses of IgG antibodies (IgG1, IgG2, IgG3, and IgG4). The distinct functions and expression patterns of these receptors contribute to the complexity and fine-tuning of immune responses in the human body.

Myeloid Differentiation Factor 88 (MYD88) is a signaling adaptor protein that plays a crucial role in the innate immune response. It is involved in the signal transduction pathways of several Toll-like receptors (TLRs), which are pattern recognition receptors that recognize pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs).

Upon activation of TLRs, MYD88 is recruited to the receptor complex where it interacts with IL-1 receptor-associated kinase 4 (IRAK4) and activates IRAK1. This leads to the activation of downstream signaling pathways, including the mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB), resulting in the production of proinflammatory cytokines and type I interferons.

MYD88 is widely expressed in various cell types, including hematopoietic cells, endothelial cells, and fibroblasts. Mutations in MYD88 have been associated with several human diseases, such as lymphomas, leukemias, and autoimmune disorders.

A viral vaccine is a biological preparation that introduces your body to a specific virus in a way that helps your immune system build up protection against the virus without causing the illness. Viral vaccines can be made from weakened or inactivated forms of the virus, or parts of the virus such as proteins or sugars. Once introduced to the body, the immune system recognizes the virus as foreign and produces an immune response, including the production of antibodies. These antibodies remain in the body and provide immunity against future infection with that specific virus.

Viral vaccines are important tools for preventing infectious diseases caused by viruses, such as influenza, measles, mumps, rubella, polio, hepatitis A and B, rabies, rotavirus, chickenpox, shingles, and some types of cancer. Vaccination programs have led to the control or elimination of many infectious diseases that were once common.

It's important to note that viral vaccines are not effective against bacterial infections, and separate vaccines must be developed for each type of virus. Additionally, because viruses can mutate over time, it is necessary to update some viral vaccines periodically to ensure continued protection.

Aging is a complex, progressive and inevitable process of bodily changes over time, characterized by the accumulation of cellular damage and degenerative changes that eventually lead to increased vulnerability to disease and death. It involves various biological, genetic, environmental, and lifestyle factors that contribute to the decline in physical and mental functions. The medical field studies aging through the discipline of gerontology, which aims to understand the underlying mechanisms of aging and develop interventions to promote healthy aging and extend the human healthspan.

An antigen is any substance that can stimulate an immune response, particularly the production of antibodies. Viral antigens are antigens that are found on or produced by viruses. They can be proteins, glycoproteins, or carbohydrates present on the surface or inside the viral particle.

Viral antigens play a crucial role in the immune system's recognition and response to viral infections. When a virus infects a host cell, it may display its antigens on the surface of the infected cell. This allows the immune system to recognize and target the infected cells for destruction, thereby limiting the spread of the virus.

Viral antigens are also important targets for vaccines. Vaccines typically work by introducing a harmless form of a viral antigen to the body, which then stimulates the production of antibodies and memory T-cells that can recognize and respond quickly and effectively to future infections with the actual virus.

It's worth noting that different types of viruses have different antigens, and these antigens can vary between strains of the same virus. This is why there are often different vaccines available for different viral diseases, and why flu vaccines need to be updated every year to account for changes in the circulating influenza virus strains.

The Major Histocompatibility Complex (MHC) is a group of cell surface proteins in vertebrates that play a central role in the adaptive immune system. They are responsible for presenting peptide antigens to T-cells, which helps the immune system distinguish between self and non-self. The MHC is divided into two classes:

1. MHC Class I: These proteins present endogenous (intracellular) peptides to CD8+ T-cells (cytotoxic T-cells). The MHC class I molecule consists of a heavy chain and a light chain, together with an antigenic peptide.

2. MHC Class II: These proteins present exogenous (extracellular) peptides to CD4+ T-cells (helper T-cells). The MHC class II molecule is composed of two heavy chains and two light chains, together with an antigenic peptide.

MHC genes are highly polymorphic, meaning there are many different alleles within a population. This diversity allows for better recognition and presentation of various pathogens, leading to a more robust immune response. The term "histocompatibility" refers to the compatibility between donor and recipient MHC molecules in tissue transplantation. Incompatible MHC molecules can lead to rejection of the transplanted tissue due to an activated immune response against the foreign MHC antigens.

Dehydration is a condition that occurs when your body loses more fluids than it takes in. It's normal to lose water throughout the day through activities like breathing, sweating, and urinating; however, if you don't replenish this lost fluid, your body can become dehydrated.

Mild to moderate dehydration can cause symptoms such as:
- Dry mouth
- Fatigue or weakness
- Dizziness or lightheadedness
- Headache
- Dark colored urine
- Muscle cramps

Severe dehydration can lead to more serious health problems, including heat injury, urinary and kidney problems, seizures, and even hypovolemic shock, a life-threatening condition that occurs when your blood volume is too low.

Dehydration can be caused by various factors such as illness (e.g., diarrhea, vomiting), excessive sweating, high fever, burns, alcohol consumption, and certain medications. It's essential to stay hydrated by drinking plenty of fluids, especially during hot weather, exercise, or when you're ill.

In medical terms, the skin is the largest organ of the human body. It consists of two main layers: the epidermis (outer layer) and dermis (inner layer), as well as accessory structures like hair follicles, sweat glands, and oil glands. The skin plays a crucial role in protecting us from external factors such as bacteria, viruses, and environmental hazards, while also regulating body temperature and enabling the sense of touch.

The term "Immune Adherence Reaction" is not widely used in modern immunology or medicine. It appears to be an outdated concept that refers to the attachment of immune complexes (consisting of antigens, antibodies, and complement components) to Fc receptors on phagocytic cells, such as neutrophils and monocytes. This interaction facilitates the clearance of immune complexes from circulation and helps to prevent tissue damage caused by their deposition.

However, it is important to note that this term is not commonly used in current scientific literature or clinical settings. Instead, the processes it describes are typically discussed within the broader context of immune complex-mediated inflammation, complement activation, and phagocytosis.

... Network International Conference on Immune Tolerance Immune+tolerance at the U.S. National Library of Medicine ... Immune tolerance is important for normal physiology. Central tolerance is the main way the immune system learns to discriminate ... Immune tolerance, or immunological tolerance, or immunotolerance, is a state of unresponsiveness of the immune system to ... see Immune response). Tolerance is classified into central tolerance or peripheral tolerance depending on where the state is ...
... or maternal immune tolerance is the immune tolerance shown towards the fetus and placenta during ... and a chronic insufficient tolerance may cause infertility. Other examples of insufficient immune tolerance in pregnancy are Rh ... This tolerance counters the immune response that would normally result in the rejection of something foreign in the body, as ... The increased immune tolerance is believed to be a major contributing factor to an increased susceptibility and severity of ...
Steinman, Ralph M. (2004). "Dendritic Cells and Immune Tolerance". The Rockefeller University. Archived from the original on ... The first type of tolerance is central tolerance, that occurs in the thymus. T cells that bind (via their T cell receptor) to ... The second type of immunological tolerance is peripheral tolerance. Some self reactive T cells escape the thymus for a number ... This process is called tolerance. Dendritic cells also promote immunological tolerance, which stops the body from attacking ...
Sakaguchi S, Yamaguchi T, Nomura T, Ono M (May 2008). "Regulatory T cells and immune tolerance". Cell. 133 (5): 775-787. doi: ... Anaphylaxis may be a side effect, as the CAR is made with a foreign monoclonal antibody, and as a result provokes an immune ... T cells can also mediate tolerance to antigens. A regulatory T cell outfitted with a CAR could have the potential to confer ... Cytokines, innate immune receptors, TNF receptors, growth factors, and structural proteins have all been successfully used as ...
It is one method of immune tolerance. Frank Macfarlane Burnet proposed autoreactive cells would be terminated before maturation ... Thus, the host develops a tolerance for this antigen, or a self tolerance. B and T lymphocytes are tested for their affinity ... Central tolerance prevents B and T lymphocytes from reacting to self. Thus, clonal deletion can help protect individuals ... This prevents recognition and destruction of self host cells, making it a type of negative selection or central tolerance. ...
... this is a type of immune tolerance. The more specific and sensitive RT-PCR test for HIV's genome does not appear to have been ...
Immune tolerance therapies seek to reset the immune system so that the body stops mistakenly attacking its own organs or cells ... The transfer of regulatory immune cells has the potential to inhibit the activity of effector. Creating immune tolerance ... Rotrosen D, Matthews JB, Bluestone JA (July 2002). "The immune tolerance network: a new paradigm for developing tolerance- ... Stolp J, Zaitsu M, Wood KJ (2019). "Immune Tolerance and Rejection in Organ Transplantation". Immunological Tolerance. Methods ...
In aging of the immune system is also a decrease in central tolerance and an increase in the number of autoreactive T cells. B ... APECED causes loss of central immune tolerance. Omenn syndrome manifests as GVHD (graft versus host disease)-like autoimmune ... Immune dysregulation is any proposed or confirmed breakdown or maladaptive change in molecular control of immune system ... Immune system dysfunction, as seen in IPEX syndrome leads to immune dysfunction, polyendocrinopathy, enteropathy, X-linked ( ...
551-557 Allen, Paul M. (2006). "Defining Yourself: Tolerance Development in the Immune System". The Journal of Immunology. 177 ... Allen's work specializes in the study of how T lymphocytes recognize antigens and initiate an immune response. He and Emil R. ...
Tolerance is a fundamental property of the immune system. Tolerance involves non-self discrimination which is the ability of ... Autoimmunity can thus be defined simply as exceptions to the tolerance "rules." By doing this, an immune response is generated ... Tolerance is also produced in B cells. There are also various processes which lead to B cell tolerance. Just as in T cells, ... T cell tolerance then must occur within the periphery after the induction of T cell tolerance within the thymus as a more ...
"Immune Tolerance-Adjusted Personalized Immunogenicity Prediction for Pompe Disease". Frontiers in Immunology. 12: 636731. doi: ... De Groot, Martin and Moise also developed the JanusMatrix tool, that identifies regions of "immune camouflage" used by ... "Identification and Immune Assessment of T Cell Epitopes in Five Plasmodium falciparum Blood Stage Antigens to Facilitate ... that are shown to activate regulatory T cells and suppress the immune response. ...
APS-1 is due to problems with immune tolerance. APS-1 causes considerable reactions with both interferon omega and interferon ... which is located on chromosome 21 and normally confers immune tolerance. APS-1 tends to cause severe symptoms. These are ...
Lu M, Varley AW, Munford RS (May 2013). "Persistently active microbial molecules prolong innate immune tolerance in vivo". PLOS ... The LPS-injected mice develop strikingly high titers of polyclonal antibodies, prolonged hepatomegaly, and innate immune " ... "tolerance" that results in slow and inadequate responses to a bacterial challenge. Absence of the enzyme renders mice more ... "Host inactivation of bacterial lipopolysaccharide prevents prolonged tolerance following gram-negative bacterial infection". ...
Their main functions involve maintaining self-tolerance and immune homeostasis. Treg differentiation is induced by expression ... Paradoxical effects of cytokines in tumor immune surveillance and tumor immune escape. Cytokine and Growth Factor Reviews 18, ... These T cells produce high levels of IL-10 and TGF-β, thereby suppressing the immune system and allowing for evasion by the ... Immune interferon: a pleiotropic lymphokine with multiple effects. Immunology Today 6:4, pp. 131-136 Wang, Rong-Fu., 2001. The ...
During this time, she also did a postdoctoral fellowship in human immune tolerance mechanisms in asthma and allergy. In 2006, ... Nadeau's laboratory is working on scientific investigations of immune tolerance. Areas of research include: Translational work ... This research led to novel findings on markers of immune tolerance in a pilot clinical trial using peanut oral immunotherapy ... "Environmental Factor - January 2015: The impacts of air pollution on the immune system". factor.niehs.nih.gov. Retrieved 2019- ...
Bertoletti A, Gehring A (October 2007). "Immune response and tolerance during chronic hepatitis B virus infection". Hepatology ... Not all virus infections produce a protective immune response in this way. HIV evades the immune system by constantly changing ... Viral infections in animals provoke an immune response that usually eliminates the infecting virus. Immune responses can also ... are disseminated by neural spread where the immune system may be unable to reach them due to immune privilege. Because viruses ...
miRNA found in milk-derived exosomes may increase immune tolerance. Metabolic disease, and particularly type 2 diabetes ... During this time frame of early childhood growth, there are many immune and developmental pathways that are dependent on ... Present in human milk are HMOs, bioactive components which aid in immune function and regulation, and miRNA-containing exosomes ... In addition to adverse effects on mental health, children who experience these events often exhibit dampened immune responses. ...
Once acquired, individuals with BVDV can gain lifelong immune tolerance. Java mouse-deer is currently categorized as "Data ...
... plays a role in immune tolerance in pregnancy, being expressed in the placenta by extravillous trophoblast cells (EVT), ... Zhuang B, Shang J, Yao Y (2021). "HLA-G: An Important Mediator of Maternal-Fetal Immune-Tolerance". Frontiers in Immunology. 12 ... HLA-G is a major immune checkpoint, meaning it downregulates the immune system's response. Soluble HLA-G can be found in the ... HLA-G has been shown to be associated with tumor escape in cancers, because it causes the immune system to not pay attention to ...
... peripheral tolerance is the second branch of immunological tolerance, after central tolerance. It takes place in the immune ... Peripheral tolerance prevents immune response to harmless food antigens and allergens, too. Deletion of self-reactive T cells ... Tregs are the central mediators of immune suppression and they play a key role in maintaining peripheral tolerance. The master ... Specialized mechanisms ensuring ignorance by the immune system have developed in so-called immune privileged organs. The ...
Co-Chairman of the Autoimmunity Committee of the Immune Tolerance Network; Naomi M. Kanof Award for Distinguished Achievement ... Chairman NIH Immunological Sciences and Hyper-accelerated Award/Mechanisms in Immune Disease Study Sections, HHMI Review Panel ...
Together they demonstrated immune tolerance as proposed by Frank Macfarlane Burnet. Burnet and Medawar received the Nobel Prize ...
Malchow S, Leventhal DS, Lee V, Nishi S, Socci ND, Savage PA (May 2016). "Aire Enforces Immune Tolerance by Directing ... van Delft MA, Huitema LF, Tas SW (May 2015). "The contribution of NF-κB signalling to immune regulation and tolerance". ... "Fezf2 Orchestrates a Thymic Program of Self-Antigen Expression for Immune Tolerance". Cell. 163 (4): 975-87. doi:10.1016/j.cell ... dominant tolerance). How mTECs discriminate between these two modes of tolerance? It was shown that prospective TRegs interact ...
The role of inducing immune tolerance has yet to be established. Shanmuganathan, Mayooran; Dar, Owais (2020). "73. ...
This lack of immune tolerance is probably due to the non-specific activity of Brucella's particulate extracts on the maturation ... A new approach to immune tolerance The dogma of the time that the newborn animal or human being was tolerant to a foreign ... Work on immune tolerance had previously been conducted with soluble antigens. Using a particulate antigen extracted from ... This observation relating to immune tolerance, as well as a clinical observation, led to a new direction in Charles Pilet's ...
PD-L2 plays an important role in immune tolerance and autoimmunity. Both PD-L1 and PD-L2 can inhibit T cell proliferation and ... PDCD1LG2 is an immune checkpoint receptor ligand which plays a role in negative regulation of the adaptive immune response. PD- ... Due to their role in suppressing the adaptive immune system, efforts have been made to block PD-1 and PD-L1, resulting in FDA ... The direct role of PD-L2 in cancer progression and immune-tumor microenvironment regulation is not as well studied as the role ...
"Operational tolerance vs immune suppression, targeting the αβ TCR with TOL101". American Journal of Transplantation. 10 (Suppl ... but are also capable of modulating many other aspects of the immune system, often resulting in long-term broad spectrum immune ... Chatenoud L (2010). "Immune therapy for type 1 diabetes mellitus-what is unique about anti-CD3 antibodies?". Nature Reviews ... Beetz S, Wesch D, Marischen L, Welte S, Oberg HH, Kabelitz D (2008). "Innate immune functions of human gammadelta T cells". ...
Burnet developed the ideas of clonal selection and acquired immune tolerance. Later, Professor Donald Metcalf discovered and ... "Infectious Diseases and Immune Defence". WEHI. 17 April 2019. "Inflammation". WEHI. 24 October 2014. "Personalised Oncology". ... Infectious Diseases and Immune Defence (A/Professor Wai-Hong Tham and Professor Marc Pellegrini) Inflammation (Associate ... with its scientists making important discoveries in the control of immune system responses, cell cycle regulation and malaria. ...
"Fezf2 Orchestrates a Thymic Program of Self-Antigen Expression for Immune Tolerance". Cell. 163 (4): 975-987. doi:10.1016/j. ... "Enteric α-defensins on the verge of intestinal immune tolerance and inflammation". Seminars in Cell & Developmental Biology. 88 ... "The contribution of NF-κB signalling to immune regulation and tolerance". European Journal of Clinical Investigation. 45 (5): ... "Identification of a novel cis-regulatory element essential for immune tolerance". Journal of Experimental Medicine. 212 (12): ...
These results suggest that hCG may be a link in the development of peritrophoblastic immune tolerance, and may facilitate the ... "Human chorionic gonadotropin as a central regulator of pregnancy immune tolerance". Journal of Immunology. 190 (6): 2650-2658. ... In order to induce a stronger immune response, some versions of human chorionic gonadotropin-based anti-fertility vaccines were ...
Immune Tolerance Network International Conference on Immune Tolerance Immune+tolerance at the U.S. National Library of Medicine ... Immune tolerance is important for normal physiology. Central tolerance is the main way the immune system learns to discriminate ... Immune tolerance, or immunological tolerance, or immunotolerance, is a state of unresponsiveness of the immune system to ... see Immune response). Tolerance is classified into central tolerance or peripheral tolerance depending on where the state is ...
Nearly a third of these genes are predominantly expressed in messenger cells of the immune system known as dendritic cells. Of ...
The demonstration of T cell tolerance, particularly that mediated by the immune-suppressive functions of IL-10, led to a major ... Mechanisms of immune tolerance to allergens: role of IL-10 and Tregs. ... Mechanisms of immune tolerance to allergens: role of IL-10 and Tregs. ... Currently, the known essential components of allergen tolerance include the induction of allergen-specific regulatory subsets ...
Diamond B, Bluestone J, Wofsy D (2001). The Immune Tolerance Network and rheumatic disease: immune tolerance comes to the ... Bluestone JA, Matthews J (2001). The Immune Tolerance Network: tolerance at the crossroads. Philos Trans R Soc Lond B Biol Sci ... Clair EW, Turka LA (2010). Immune Tolerance Network at 10 years: Tolerance research at the bedside. Nat Rev Immunol, 10 (11), ... Ehlers MR, Nepom GT (2012). Immune-directed therapy for type 1 diabetes at the clinical level: the Immune Tolerance Network ( ...
... disturb immune tolerance (4). Loss of immune tolerance to autoantigens associated with a specific organ results in the ... immune tolerance. Citation: Moorman CD, Sohn SJ and Phee H (2021) Emerging Therapeutics for Immune Tolerance: Tolerogenic ... Tregs as the Master Regulators of Immune Tolerance. Immunosuppressive CD4+ FOXP3+ Tregs are required for immune tolerance. ... Antigen-Specific Immune Tolerance. Risks associated systemic immune suppression or immunomodulatory therapies for the treatment ...
Key Words: Immature dendritic cells, Induced pluripotent stem cells, Sinomenine, Immune tolerance, Organ transplantation ... and higher regulatory T-cell proliferative function in vitro and in vivo to induce high immune tolerance. It provided a new ... play an important role in the induction of donor-specific transplant immune tolerance. However, these cells have limitations, ... differentiation of induced pluripotent stem cells into immature dendritic cells with high induction of immune tolerance. World ...
Immune tolerance induction in development. *Mark. Berntorp, Erik LU (2023) In Blood 141(16). p.1901-1902 Links. *Research ... Immune tolerance induction in development}}, url = {{http://dx.doi.org/10.1182/blood.2022019465}}, doi = {{10.1182/blood. ...
Immune tolerance in multiple sclerosis and neuromyelitis optica with peptide-loaded tolerogenic dendritic cells in a phase 1b ... About NMONeuromyelitis optica (NMO) and neuromyelitis optica spectrum disorder (NMOSD) occur when the immune system mistakes ... One approach involves induction of tolerance with engineered dendritic cells (tolDCs) loaded with specific antigens. We ... Strategies aimed at antigen-specific tolerance to these autoantigens are thus indicated for these diseases. ...
... can induce the complex immune response pattern of endotoxin tolerance in mammary epithelial cells. In: Innate Immunity, Vol. 23 ... while stimulating the expression of immune defense genes during a subsequent bacterial infection. This endotoxin tolerance (ET ... Hence, triggering immune functions via the TLR axis, but not through those histone modifiers, induced the beneficial phenomenon ... Excessive stimulation of the TLR4 axis through LPS reduces the expression of some cytokine genes in immune cells, ...
Three Steps to Breaking Immune Tolerance to Lymphoma: A Microparticle Approach Amani Makkouk; Amani Makkouk ... The goal of many forms of cancer immunotherapy is to overcome immunologic tolerance to tumor antigens and generate immune ... Nano-microparticles as immune adjuvants: correlating particle sizes and the resultant immune responses ... Three Steps to Breaking Immune Tolerance to Lymphoma: A Microparticle Approach. Cancer Immunol Res 1 April 2015; 3 (4): 389-398 ...
Immune Tolerance PubMed MeSh Term *Overview. Overview. subject area of * Circumventing the immune response to adenovirus- ... Stochastic approximation to the T cell mediated specific response of the immune system Journal Article ...
Immune tolerance induction. In immune tolerance induction (ITI), patients are rendered tolerant to FIX by means of daily ... An international immune tolerance study was started in 2002 to compare the efficiency, morbidity, and cost-effectiveness of low ... Factor VIII gene (F8) mutations as predictors of outcome in immune tolerance induction of hemophilia A patients with high- ... For information, please see the study Web site Immune Tolerance Induction Study. ...
Gene, Environment, Microbiome and Mucosal Immune Tolerance in Rheumatoid Arthritis. Anca I. Catrina; Kevin D. Deane; Jose U. ... mucosal target of specific immune pathways, mucosal generation of tolerance).. ... We will also outline how microbes, as well as other factors such as smoking, can trigger immune responses at mucosal sites and ... Finally, we propose a research agenda for greater understanding of the role of mucosal immune responses in the initiation of ...
The firm will utilise Anokions tolerance-inducing technology shown to induce immune tolerance to protein drugs and autoimmune ... 760 million to create a new US-based firm focused on developing novel immune tolerance therapeutics. ...
... Rigo, Riccardo;Chelbi, Rabie;Agopian, Julie;Letard, ... Repression of these genes results in immune tolerance to acute stimulation that can be rescued with vitamin C treatment or ... Overall, our data support a model where TET2 plays a direct role in preventing immune tolerance in chronically activated mast ... Repression of these genes results in immune tolerance to acute stimulation that can be rescued with vitamin C treatment or ...
At the same time, induction of immune tolerance and the clearance of neutrophils from the site of infection are essential in ... At the same time, induction of immune tolerance and the clearance of neutrophils from the site of infection are essential in ... At the same time, induction of immune tolerance and the clearance of neutrophils from the site of infection are essential in ... At the same time, induction of immune tolerance and the clearance of neutrophils from the site of infection are essential in ...
"IgG4 immune tolerance". It describes mRNA-injected people developing so-called "IgG4 antibodies", which make their immune ... Fauci Knew Boosters Could Cause Immune Tolerance; Pushed for them Anyway. Did the science have our best interests at heart?. ... Immune tolerance, induced by frequent vaccine boosting, and the role of IgG4 antibodies in it, was therefore well known in ... The likelihood of "immune tolerance" was well within the routine knowledge of immunology and vaccinology. ...
Tolerance is generally accepted to be an active process and, in essence, a learning experience for T cells. ... Immunologic tolerance is a state of immune unresponsiveness specific to a particular antigen or set of antigens induced by ... However, during the study of achieving immune tolerance, ways in which to induce states of "partial tolerance" have been ... such as the National Institutes of Health and the Immune Tolerance Network, is to fund research to develop tolerance assays. ...
IgA immunity and oral tolerance. Thus, impaired antigen-specific Ab responses in aged animals and the elderly have been ... Age-associated dysregulation of the immune system of the gastrointestinal (GI) tract has been well documented for both ... Age-associated dysregulation of the immune system of the gastrointestinal (GI) tract has been well documented for both ... Mucosal immunity and tolerance in the elderly Mech Ageing Dev. 2004 Dec;125(12):889-98. doi: 10.1016/j.mad.2004.05.009. ...
Preventing aortic aneurysm initiation and expansion by inducing immune tolerance using nanoparticles. February 22, 2023. /by ... Preventing aortic aneurysm initiation and expansion by inducing immune tolerance using nanoparticles ... 23Preventing aortic aneurysm initiation and expansion by inducing immune tolerance using nanoparticles. ...
Interests: atherosclerosis; endothelial injury and repair; vascular regeneration; inflammation; immune tolerance; cancer; HIV ... Interests: immune response to viral infections; viral immunology; encephalitic arboviruses; viral pathogenesis; adaptive immune ... Special Issue in Vaccines: Immune Response of SARS-CoV-2 Infection. Special Issue in Vaccines: Vaccine Development for Emerging ... Interests: humoral and cell-mediated immune response to microbes; vaccination and infection in the immunocompromised host and ...
Regulatory T cells are critical for continued immune tolerance in the intestine through active control of innate and adaptive ... Instigating and maintaining immunological tolerance within the intestine represents a unique challenge to the mucosal immune ... immune responses. Dynamic adaptation of regulatory T-cell populations to the intestinal tissue microenvironment is key in this ... A fundamental role of the mammalian immune system is to eradicate pathogens while minimizing immunopathology. ...
Thymus based tolerance to stem cell therapies. This proposal focuses on the role of the immune system in transplantation of ... Engineered immune tolerance by Stem Cell-derived thymic regeneration. Stem cell therapies have the potential to transform ... In order for stem cell therapies to proceed, it will be essential that the regulation of immune responses to the stem cell ... is the fact that the immune systems main function is to prevent the introduction of foreign substances into our bodies. […] ...
... or xeno-tolerance to various solid organs. In the cells-followed-by-CP system, the sequential mechanisms of tolerance w … ... induced tolerance system in mice that primarily consists of donor cell injection followed by CP-treatment was found useful for ... or xeno-tolerance to various solid organs. In the cells-followed-by-CP system, the sequential mechanisms of tolerance were ... Cyclophosphamide-induced immunological tolerance: an overview Immunobiology. 1996 Jul;195(2):129-39. doi: 10.1016/S0171-2985(96 ...
This course is organized by Prof. Ronen Alon and is mainly targeted on students/postdocs interested to learn more about the specific fields of immunology and the most recent immunology research. Each lecture is given by departmental member, who is an expert in the particular field.. ...
Investigating immune tolerance mechanisms. *Studying cancer evasion of immune surveillance. Representative Publication. ... Frequent loss of IRF2 in cancers leads to immune evasion through decreased MHC class I antigen presentation and increased PD-L1 ...
The mechanism by which NAD+ alters the systemic immune response is unclear. Here the authors show that NAD+ induces systemic ... by inducing immune homeostasis through CD4+IFNγ+IL-10+ T cells and reverses disease progression by restoring tissue integrity ... Tryptophan hydroxylase-1 regulates immune tolerance and inflammation. J. Exp. Med. 209, 2127-2135 (2012). ... Our in vivo findings indicate that NAD+ alters the systemic immune response in EAE. Therefore, we next sought to dissect the ...
This study focused on the comparison of autologous and allogeneic immune response to iPSC-derived cells and isogeneic parental ... Bogomiakova, M.E., Sekretova, E.K., Anufrieva, K.S. et al. iPSC-derived cells lack immune tolerance to autologous NK-cells due ... Liu X, Li W, Fu X, Xu Y. The immunogenicity and immune tolerance of pluripotent stem cell derivatives. Front Immunol. 2017;8: ... iPSC-derived cells lack immune tolerance to autologous NK-cells due to imbalance in ligands for activating and inhibitory NK- ...
  • Immune tolerance, or immunological tolerance, or immunotolerance, is a state of unresponsiveness of the immune system to substances or tissue that would otherwise have the capacity to elicit an immune response in a given organism. (wikipedia.org)
  • There are two mechanisms that maintain immunological tolerance denominated central and peripheral tolerance. (frontiersin.org)
  • Instigating and maintaining immunological tolerance within the intestine represents a unique challenge to the mucosal immune system. (ox.ac.uk)
  • During the past 20 years, major advances have been made in understanding the molecular and cellular mechanisms of allergen tolerance in humans. (jci.org)
  • Induction of immunologic tolerance has been achieved and studied in numerous laboratory animal models, but it remains an elusive goal in clinical organ transplantation and in the management of autoimmune disease in humans. (medscape.com)
  • It is used to describe the phenomenon underlying discrimination of self from non-self, suppressing allergic responses, allowing chronic infection instead of rejection and elimination, and preventing attack of fetuses by the maternal immune system. (wikipedia.org)
  • Currently, the known essential components of allergen tolerance include the induction of allergen-specific regulatory subsets of T and B cells, the immune-suppressive function of secreted factors, such as IL-10 and TGF-β, the production of IgG4 isotype allergen-specific blocking antibodies, and decreased allergic inflammatory responses by mast cells, basophils, and eosinophils in inflamed tissues. (jci.org)
  • The next wave of truly transformative therapeutics should aspire to provide a cure by selectively suppressing pathogenic autoantigen-specific immune responses while leaving the rest of the immune system intact to control infectious diseases and malignancies. (frontiersin.org)
  • The mammalian immune system evolved to protect our bodies from foreign pathogens and intrinsic aberrant malignancies while concurrently preventing deleterious immune responses toward self ( 1 ). (frontiersin.org)
  • In situ immunization aims at generating antitumor immune responses through manipulating the tumor microenvironment. (aacrjournals.org)
  • In mice, this three-step therapy induced CD4- and CD8-dependent systemic immune responses that enhanced T-cell infiltration into distant tumors, leading to their eradication and significantly improving survival. (aacrjournals.org)
  • In particular we will examine the role of microbes in shaping mucosal and systemic immune responses. (medscape.com)
  • We will also outline how microbes, as well as other factors such as smoking, can trigger immune responses at mucosal sites and eventually lead to RA. (medscape.com)
  • Finally, we propose a research agenda for greater understanding of the role of mucosal immune responses in the initiation of autoimmunity and RA. (medscape.com)
  • Further, it has been shown that gut-associated lymphoreticular tissue (GALT) mediated immune responses are more susceptible to aging than are lymphoid tissues involved in peripheral immunity. (nih.gov)
  • Despite these studies, the precise mechanisms for impaired GI tract immune system responses remain unclear. (nih.gov)
  • Self-tolerance and of immune responses against tumour cells. (translateinthetownships.com)
  • It plays a part in various inflammatory ailments by initiating immune and inflammatory responses [35]. (translateinthetownships.com)
  • Regulatory T cells are critical for continued immune tolerance in the intestine through active control of innate and adaptive immune responses. (ox.ac.uk)
  • In order for stem cell therapies to proceed, it will be essential that the regulation of immune responses to the stem cell derived tissues be achieved. (ca.gov)
  • For this reason, the skin is often exposed to potentially hazardous agents, including chemicals, which may contribute to the onset of a spectrum of adverse health effects ranging from localized damage (e.g., irritant contact dermatitis and corrosion) to induction of immune-mediated responses (e.g., allergic contact dermatitis and pulmonary responses), or systemic toxicity (e.g., neurotoxicity and hepatoxicity). (cdc.gov)
  • This document provides the scientific rationale and framework for the assignment of multiple hazard-specific skin notations (SK) that clearly distinguish between the systemic effects, direct (localized) effects, and immune-mediated responses caused by skin contact with chemicals. (cdc.gov)
  • Currently, many of these strategies are focused on overcoming stromal barriers to anti-tumor immune responses such that men suffering from prostate cancer can share in the immense, revolutionary power of immunotherapy that is transforming care for many with advanced disease in other tumor types previously thought to be unmanageable using conventional approaches. (hopkinsmedicine.org)
  • Unfortunately, prostate cancer has largely proven refractory to these powerful approaches thus far and requires novel mono- or combinatorial treatment strategies to unleash the full potential of the immune system and generate personalized anti-tumor responses with the capability of producing long-term durable responses or even cures in these men. (hopkinsmedicine.org)
  • Our primary pursuits are discovering and elucidating new molecules that regulate immune responses, investigating the biology of regulatory T cells, and better understanding the specific biochemical signatures that allow a patient's T cells to selectively target cancer cells. (hopkinsmedicine.org)
  • Little is known about the broad effects of the new class of mRNA vaccines, especially whether they have combined effects on innate and adaptive immune responses. (ssrn.com)
  • The response of innate immune cells to TLR4 and TLR7/8 ligands was lower after BNT162b2 vaccination, while fungi-induced cytokine responses were stronger. (ssrn.com)
  • In conclusion, the mRNA BNT162b2 vaccine induces complex functional reprogramming of innate immune responses, which should be considered in the development and use of this new class of vaccines. (ssrn.com)
  • ImmTOR ® and ImmTOR-ILâ„¢ comprise an immune tolerance platform designed to give rise to antigen-specific immunity, mitigating unwanted immune responses. (selectabio.com)
  • Understanding the immune suppression in breast cancer patients may lead to insights into treatment responses, resistance mechanisms and novel treatment modalities aimed to hinder this phenomenon which would eventually encumber the devastating progression of breast cancer metastasis. (lu.se)
  • Thus, therapeutics that induce, restore, and maintain immune tolerance toward these autoantigens represent the "Holy Grail" of treatments for autoimmune diseases. (frontiersin.org)
  • This study focused on exploring sinomenine (SN) to promote differentiation of induced pluripotent stem cells (iPSCs) into imDCs (SN-iPSCs-imDCs), and found SN-iPSCs-imDCs with worse donor-specific T-cell stimulatory function, and higher regulatory T-cell proliferative function in vitro and in vivo to induce high immune tolerance. (newswise.com)
  • However, during the study of achieving immune tolerance, ways in which to induce states of "partial tolerance" have been discovered, in which lower-than-conventional amounts of ongoing pharmacologic immunosuppression are needed. (medscape.com)
  • ImmTOR ® has the potential to induce adeno-associated virus (AAV) vector-specific immune tolerance, reducing the severity of the body's immune response to AAV gene therapy and enabling repeat administrations. (selectabio.com)
  • The mechanisms by which these forms of tolerance are established are distinct, but the resulting effect is similar. (wikipedia.org)
  • Immune tolerance encompasses the range of physiological mechanisms by which the body reduces or eliminates an immune response to particular agents. (wikipedia.org)
  • Mechanisms of peripheral tolerance include inactivation of autoantigen-recognizing T and B cells by the induction of apoptosis, anergy or conversion into immunosuppressive regulatory cells. (frontiersin.org)
  • This endotoxin tolerance (ET) is mediated via epigenetic mechanisms. (uni-muenchen.de)
  • In the cells-followed-by-CP system, the sequential mechanisms of tolerance were clarified using the specific correlation between superantigens and certain T cell receptor (TCR) V beta segments. (nih.gov)
  • Mapping the epigenomic landscape of human monocytes following innate immune activation reveals context-specific mechanisms driving endotoxin tolerance. (ox.ac.uk)
  • The ITI is interested in understanding the underlying biology of those diseases and mechanisms that can be defined better by biomarkers predicting drug safety and efficacy, but we are also very much interested in those conditions where the immune system, properly mobilized, could play a major role as part of a therapeutic armamentarium. (drugdiscoverynews.com)
  • To study the mechanisms behind how the innate immune system in late stage cancer patients is suppressed, with consequences and how to restore it. (lu.se)
  • All these mechanisms are mediated by innate immune cells. (lu.se)
  • The development of antigen-specific immunotherapy for complete cure of allergies and autoimmune diseases, which artificially induces immune tolerance to antigens, has been studied. (elsevierpure.com)
  • Non-depleting anti-CD4 monoclonal antibody induces immune tolerance to ERT in a murine model of Pompe disease. (ox.ac.uk)
  • Immune tolerance co-evolved as a safety system that maintains a state of immune unresponsiveness to autoantigens and self-tissues ( 2 , 3 ). (frontiersin.org)
  • Immunologic tolerance is a state of immune unresponsiveness specific to a particular antigen or set of antigens induced by previous exposure to that antigen or set. (medscape.com)
  • Age-associated dysregulation of the immune system of the gastrointestinal (GI) tract has been well documented for both secretory (S)-IgA immunity and oral tolerance. (nih.gov)
  • Indeed, the frequencies of naive CD4+ T cells and dendritic cells (DCs) in Peyer's patches of aged mice were reduced and this led to a lack of essential cytokine synthesis for the induction of either S-IgA immunity or oral tolerance. (nih.gov)
  • BackgroundMonocytes are key mediators of innate immunity to infection, undergoing profound and dynamic changes in epigenetic state and immune function which are broadly protective but may be dysregulated in disease. (ox.ac.uk)
  • It is induced by prior exposure to that specific antigen and contrasts with conventional immune-mediated elimination of foreign antigens (see Immune response). (wikipedia.org)
  • One approach involves induction of tolerance with engineered dendritic cells (tolDCs) loaded with specific antigens. (guthyjacksonfoundation.org)
  • Allergies and autoimmune diseases caused by the breakdown of immune tolerance to harmless foreign antigens and self-antigens have been attracting attention in recent years as the number of patients increases. (elsevierpure.com)
  • Immune tolerance therapy requires efficient and specific delivery of antigens to target immune cells, followed by induction of immune cells into a tolerogenic phenotype or anergy. (elsevierpure.com)
  • Our approach to autoimmune disease is highly differentiated and designed to restore natural immune system balance in vivo by co-administering IL-2 and ImmTOR ® (ImmTOR-ILâ„¢) with nanoparticle-encapsulated self-antigens and avoid the need for chronic and systemic immune suppression. (selectabio.com)
  • Second, T cell therapies using Tregs (either polyclonal, antigen-specific, or genetically engineered to express chimeric antigen receptors) to establish active dominant immune tolerance or T cells (engineered to express chimeric antigen receptors) to delete pathogenic immune cells. (frontiersin.org)
  • Strategies aimed at antigen-specific tolerance to these autoantigens are thus indicated for these diseases. (guthyjacksonfoundation.org)
  • Elicitation of specific IL-10 production by peptide-specific T cells in MS and NMOSD patients indicates that a key element in antigen specific tolerance is activated with this approach. (guthyjacksonfoundation.org)
  • In this process, drugs are required to perform three functions:evasion of the immune response to the antigen, targeting of the immune cells, and regulation of the immune cells. (elsevierpure.com)
  • In this review, strategies and drug design for inducing antigen-specific immune tolerance are outlined, examples of recent research are presented, and future prospects are discussed. (elsevierpure.com)
  • Liu, Y & Mori, T 2022, ' Drug design for induction of antigen-specific immune tolerance ', Drug Delivery System , vol. 37, no. 2, pp. 142-148. (elsevierpure.com)
  • Induction of antigen-specific immune tolerance would greatly enhance ERT for these patients. (ox.ac.uk)
  • Frequent loss of IRF2 in cancers leads to immune evasion through decreased MHC class I antigen presentation and increased PD-L1 expression. (umassmed.edu)
  • Li Z, Chen Z, Cheng X, Wu X, Li G, Zhen Y, Cai S, Poon M-, Wu R. Baseline VWF Antigen Level Is Associated with the Outcome of Immune Tolerance Induction Using pdFVIII/VWF Concentrate in Hemophilia A with Inhibitor [abstract]. (isth.org)
  • Transplantation tolerance could eliminate many of the adverse events associated with immunosuppressive agents. (medscape.com)
  • Nonetheless, immune tolerance remains the holy grail of transplantation immunology and clinical transplantation. (medscape.com)
  • This proposal focuses on the role of the immune system in transplantation of derivatives of human pluripotent stem cells (hPSCs). (ca.gov)
  • Yet, while the ITN is focused on autoimmune diseases such as asthma, allergy and transplantation with a mission to identify markers of immune tolerance, Matis says ITI's mission is broader. (drugdiscoverynews.com)
  • Far from being an obscure immunology topic, knowledge about the IgG4 antibody subclass (intended by nature for allergens and such) being suboptimal for immune response to a replicating virus such as Sars-Cov-2 was well known in immunology. (igor-chudov.com)
  • The science of immunology has been familiar with how repeated immunizations produce IgG4 antibody subclass and create immune tolerance since at least 1989. (igor-chudov.com)
  • SAN FRANCISCO-With a stated goal of creating a new, more effective model for the development of immune disease-focused therapeutics, the Immune Tolerance Institute (ITI) announced at the end of March a collaboration with Beckman Coulter to establish a Center for Critical Path Immunology. (drugdiscoverynews.com)
  • The effect of Von Willebrand factor (VWF) on immune tolerance induction (ITI) in severe hemophilia A patients with inhibitor had not been clearly unveiled. (isth.org)
  • present important information on the value of heat treatment of specimens for inhibitor measurement in hemophilia A patients undergoing immune tolerance induction therapy (ITI). (cdc.gov)
  • CD4 + T helper (Th) cells play a central role in regulating the adaptive immune response associated with pathogen invasion. (nature.com)
  • The adaptive immune system is involved in tumor establishment and aggressiveness. (ox.ac.uk)
  • Lymphocytes of the adaptive immune system can eradicate tumor cells. (lu.se)
  • Peripheral tolerance is key to preventing over-reactivity of the immune system to various environmental entities (allergens, gut microbes, etc. (wikipedia.org)
  • Immune tolerance also does not usually refer to artificially induced immunosuppression by corticosteroids, lymphotoxic chemotherapy agents, sublethal irradiation, etc. (wikipedia.org)
  • Transplant tolerance is defined as a state of donor-specific unresponsiveness without a need for ongoing pharmacologic immunosuppression. (medscape.com)
  • We further use this to inform understanding of reported GWAS, for example involving FCHO1 and coronary artery disease.ConclusionThis study reports context-specific regulatory elements based on transcriptomic profiling and epigenetic signatures for enhancer-derived RNAs and chromatin accessibility in immune tolerant monocyte states, and demonstrates the informativeness of linking such elements and eQTL to inform future mechanistic studies aimed at defining therapeutic targets of immunosuppression and diseases. (ox.ac.uk)
  • The recent identification of a number of genes affecting MS susceptibility may provide a valuable avenue to finding out more about the role of vitamin D in MS. Nearly a third of these genes are predominantly expressed in messenger cells of the immune system known as dendritic cells. (msaustralia.org.au)
  • Immature dendritic cells (imDCs) play an important role in the induction of donor-specific transplant immune tolerance. (newswise.com)
  • Immune tolerance in multiple sclerosis and neuromyelitis optica with peptide-loaded tolerogenic dendritic cells in a phase 1b trial. (guthyjacksonfoundation.org)
  • [13] The biofilm bacteria can share nutrients and are sheltered from harmful factors in the environment, such as desiccation, antibiotics, and a host body's immune system. (wikipedia.org)
  • Other features of APECED result from the body's immune system attacking the network of hormone-producing glands (the endocrine system). (medlineplus.gov)
  • A fundamental role of the mammalian immune system is to eradicate pathogens while minimizing immunopathology. (ox.ac.uk)
  • Interestingly, however, the BNT162b2 vaccine also modulated the production of inflammatory cytokines by innate immune cells upon stimulation with both specific (SARS-CoV-2) and non-specific (viral, fungal and bacterial) stimuli. (ssrn.com)
  • Here, we aimed to advance understanding of epigenetic regulation following innate immune activation, acutely and in endotoxin tolerant states.MethodsWe exposed human primary monocytes from healthy donors (n = 6) to interferon-γ or differing combinations of endotoxin (lipopolysaccharide), including acute response (2 h) and two models of endotoxin tolerance: repeated stimulations (6 + 6 h) and prolonged exposure to endotoxin (24 h). (ox.ac.uk)
  • The endotoxin tolerance models showed distinct chromatin accessibility and transcriptomic signatures, with integrated analysis identifying genes and pathways involved in the inflammatory response, detoxification, metabolism and wound healing. (ox.ac.uk)
  • Japanese drugmaker Astellas and Swiss biotech Anokion have hooked up in a deal worth $760 million to create a new US-based firm focused on developing novel immune tolerance therapeutics. (borderless.net)
  • Excessive stimulation of the TLR4 axis through LPS reduces the expression of some cytokine genes in immune cells, while stimulating the expression of immune defense genes during a subsequent bacterial infection. (uni-muenchen.de)
  • In TET2-deficient mast cells, chronic activation via the oncogenic KITD816V allele associated with mastocytosis, selects for a specific epigenetic signature characterized by hypermethylated DNA regions (HMR) at immune response genes. (unipd.it)
  • H3K27ac and transcription factor binding is consistent with priming or more open chromatin at both HMR and non-HMR in proximity to immune genes in these cells, and this signature coincides with increased pathological inflammation signals. (unipd.it)
  • HMR are also associated with a subset of immune genes that are direct targets of TET2 and repressed in TET2-deficient cells. (unipd.it)
  • Repression of these genes results in immune tolerance to acute stimulation that can be rescued with vitamin C treatment or reiterated with a Tet inhibitor. (unipd.it)
  • This could help researchers figure out common genes that relate to the body's loss of immune tolerance to its own tissues and organs," she added. (medscape.com)
  • Recent advances have been made in the of host factors, polymorphisms, and candidate genes associated characterization of the immune response to low-molecular- with occupational asthma may improve our understanding of weight agents. (cdc.gov)
  • Overall, these findings suggest that induction of an imbalanced immune tolerance in monocytes by P. gingivalis LPS, which favors continued secretion of IL-8 but decreased TNF-a production, may be associated with enhanced migration of neutrophils to the site of infection but also with decreased apoptosis and may play a role in the chronic inflammatory state seen in periodontal disease. (elsevierpure.com)
  • In addition, inducing peripheral tolerance in the local microenvironment is a common survival strategy for a number of tumors that prevents their elimination by the host immune system. (wikipedia.org)
  • The cellular ratio of immune tolerance (immunoCRIT) is a definite marker for aggressiveness of solid tumors and may explain tumor dissemination patterns. (ox.ac.uk)
  • Tumors of the ovaries, an immune-privileged organ, spread via transceolomic routes and rarely to distant organs. (ox.ac.uk)
  • This is contrary to tumors of non-immune privileged organs, which often disseminate hematogenously to distant organs. (ox.ac.uk)
  • Contrarily, non-immune privileged tumors establish high immunoCRIT in an immunological environment equivalent to the bloodstream and thus spread hematogenously to distant organs. (ox.ac.uk)
  • It is clear however, that tumors skew the immune system towards a "tolerogenic" faith, leading to immune-paralysis. (lu.se)
  • First, tolerogenic vaccines aiming at robust, lasting autoantigen-specific immune tolerance. (frontiersin.org)
  • Overall, our data support a model where TET2 plays a direct role in preventing immune tolerance in chronically activated mast cells, supporting TET2 as a viable target to reprogram the innate immune response for innovative therapies. (unipd.it)
  • A critical roadblock to successful cell replacement therapies, no matter what the disease or injury, is the fact that the immune system's main function is to prevent the introduction of foreign substances into our bodies. (ca.gov)
  • Her team collaborates extensively with faculty at the Bloomberg~Kimmel Institute for Cancer Immunotherapy and leads the BKI immunotherapy drug discovery core, aimed at developing new immune-targeting drug therapies for laboratory and clinical testing at Johns Hopkins. (hopkinsmedicine.org)
  • The intention is to provide a single lab with integrated, multiple assay platforms that can more effectively translate the identification of biomarkers into therapies to treat a broad range of diseases related to the human immune system. (drugdiscoverynews.com)
  • Therapies that alleviate persistent immune dysregulation may be a strategy to treat pain and other symptoms of GWI. (cdc.gov)
  • Central tolerance is the main way the immune system learns to discriminate self from non-self. (wikipedia.org)
  • Mucosa serves to educate the immune system, leading to a host that is more susceptible to autoimmunity through alteration of regulatory cells. (medscape.com)
  • A cyclophosphamide (CP)-induced tolerance system in mice that primarily consists of donor cell injection followed by CP-treatment was found useful for inducing a long-lasting allo- or xeno-tolerance to various solid organs. (nih.gov)
  • Matis points particularly to some forms of cancer which suppress the immune system and can be partially responsible for disappointing results in clinical trials of some cancer vaccines. (drugdiscoverynews.com)
  • ImmTOR ® and ImmTOR-ILâ„¢ have the potential to restore natural immune system balance by re-imagining immunotherapy for autoimmune disease, unlocking the potential of gene therapy and amplifying the efficacy of biologic therapy. (selectabio.com)
  • Aided by a protein in the offspring's gut lining and some immune cells, the food protein-antibody complexes are taken up and introduced to the offspring's developing immune system, triggering the production of protective cells that suppress allergic reactions to the food. (sciencedaily.com)
  • Humanized mice," in which some proteins of the mouse immune system have been replaced with human immune proteins, were protected from egg allergy by human breastmilk containing complexes of egg white protein and human antibody. (sciencedaily.com)
  • It is one of many autoimmune diseases, which are disorders that occur when the immune system malfunctions and attacks the body's own tissues and organs by mistake. (medlineplus.gov)
  • For this they need to be activated by cells of the innate immune system. (lu.se)
  • And immune tolerance in pregnancy is what allows a mother animal to gestate a genetically distinct offspring with an alloimmune response muted enough to prevent miscarriage. (wikipedia.org)
  • In their Nobel Lecture, Medawar and Burnet define immune tolerance as "a state of indifference or non-reactivity towards a substance that would normally be expected to excite an immunological response. (wikipedia.org)
  • Periodontitis, a chronic inflammatory disease of the tissues supporting the teeth, is characterized by an exaggerated host immune and inflammatory response to periopathogenic bacteria. (elsevierpure.com)
  • At the same time, induction of immune tolerance and the clearance of neutrophils from the site of infection are essential in the control of the immune response, resolution of inflammation, and prevention of tissue destruction. (elsevierpure.com)
  • This cytokine response has functional consequences for other immune cells involved in the response to infection. (elsevierpure.com)
  • It is more likely that frequent vaccinations required by the childhood vaccine schedule make children's immune response worse as they get older. (igor-chudov.com)
  • This study focused on the comparison of autologous and allogeneic immune response to iPSC-derived cells and isogeneic parental somatic cells used for reprogramming. (biomedcentral.com)
  • In pursuit of understanding biomarkers or resistance and response, and regulatory molecules of immune response, we utilize artificial intelligence, immunogenomics, and spatial proteomics and transcriptomics in the laboratory and at the bedside using clinical trial correlative samples. (hopkinsmedicine.org)
  • For many patients that require biologic therapy, the development of an immune response to the drug itself coincides with a loss of efficacy, often forcing them to discontinue treatment. (selectabio.com)
  • When ImmTOR ® is co-administered with immunogenic therapeutic biologics, it has the potential to ameliorate an immune response to the treatment, which would allow patients to continue to respond to treatment and stay on therapy longer. (selectabio.com)
  • Deliberate prevention or diminution of the host's immune response. (bvsalud.org)
  • In this state the immune response is suppressed by the tumor and even induces a wound healing processes stimulating tumor progression. (lu.se)
  • Deficits in central or peripheral tolerance also cause autoimmune disease, resulting in syndromes such as systemic lupus erythematosus, rheumatoid arthritis, type 1 diabetes, autoimmune polyendocrine syndrome type 1 (APS-1), and immunodysregulation polyendocrinopathy enteropathy X-linked syndrome (IPEX), and potentially contribute to asthma, allergy, and inflammatory bowel disease. (wikipedia.org)
  • Here we aim to boost immune tolerance to the major cat allergen Fel d 1 by increasing the anti-inflammatory activity of AIT with the established immunomodulatory adjuvant CpG, but at a higher dose than previously used in AIT. (authorea.com)
  • The regulatory immune signature also suggests the involvement of the anti-inflammatory TNF/TNFR2 signaling cascade in NK and B cells at an early stage and in Tregs later during AIT. (authorea.com)
  • Conclusion Our results highlight the potential of CpG adjuvant in a novel formulation to be further exploited for inducing allergen-specific tolerance in patients with cat allergy or other allergic diseases in the future. (authorea.com)
  • Prospective registry study for children and young adults with severe immune cytopenias (persisting/chronic immune thrombocytopenia, autoimmune hemolytic anemia, and Evans syndrome) to improve the management, facilitate the differential diagnostic work-up, and document the clinical course under various treatments. (centerwatch.com)
  • Here we show that a short-course treatment with non-depleting anti-CD4 monoclonal antibody successfully induced long-term ERT-specific immune tolerance in Pompe disease mice. (ox.ac.uk)
  • These protective cells persist after antibodies from the mother are gone, promoting long-term tolerance to the food. (sciencedaily.com)
  • Using a human monocytic cell line, we demonstrate that Porphyromonas gingivalis lipopolysaccharide (LPS), which is a major etiological factor in periodontal disease, induces only partial immune tolerance, with continued high production of interleukin-8 (IL-8) but diminished secretion of tumor necrosis factor alpha (TNF-a) after repeated challenge. (elsevierpure.com)
  • We postulate that non-pathological immunoCRIT values observed in peripheral blood of immune privileged ovarian tumor patients are sufficient to prevent hematogenous spread at primary diagnosis. (ox.ac.uk)
  • Mucosal sites might be targeted by systemic autoimmunity resulting in local immune-mediated injury. (medscape.com)
  • CD4 + T cells are involved in the development of autoimmunity, including multiple sclerosis (MS). Here we show that nicotinamide adenine dinucleotide (NAD + ) blocks experimental autoimmune encephalomyelitis (EAE), a mouse model of MS, by inducing immune homeostasis through CD4 + IFNγ + IL-10 + T cells and reverses disease progression by restoring tissue integrity via remyelination and neuroregeneration. (nature.com)
  • Loss of immune tolerance to autoantigens associated with a specific organ results in the activation of organ-specific T and B cells that in turn cause organ-specific inflammation and the development of autoimmune diseases such as multiple sclerosis (MS) ( 5 ), rheumatoid arthritis (RA) ( 6 ), psoriasis ( 7 ), and type 1 diabetes (T1D) ( 8 ). (frontiersin.org)
  • A strategy to develop tolerance would also be of value in autoimmune diseases, such as juvenile-onset diabetes mellitus , rheumatoid arthritis , and multiple sclerosis . (medscape.com)
  • The demonstration of T cell tolerance, particularly that mediated by the immune-suppressive functions of IL-10, led to a major conceptual change in this area. (jci.org)
  • Central tolerance occurs during lymphocyte development in the primary lymphoid organs (i.e. thymus and bone marrow), where T or B cell clones that recognize autoantigens with high-affinity are deleted. (frontiersin.org)
  • High dimensional CyTOF analysis of the immune cell signatures initiating and sustaining the AIT effect indicates the simultaneous engagement of both, the pDC-Treg and -B cell axis, with the emergence of a systemic GATA3+ FoxP3hi biTreg population. (authorea.com)
  • The disparity in phenotype and clinical presentation among these pathologies leads to questions regarding the role of TET2 mutation in promoting disease evolution in different immune cell types. (unipd.it)
  • Epigenetics-based immune cell quantification allows direct comparison of the immune status in benign and malignant tissues and in blood. (ox.ac.uk)
  • The peri-islet membrane, which encapsulates the islets, separates the endocrine cells from the exocrine pancreas and serves as a barrier from immune cell infiltration to the islets. (nature.com)
  • In addition, suppressor immune cells such as FOXP3 + regulatory T cells (Tregs) exert dominant immune suppression to control autoreactive T and B cells. (frontiersin.org)
  • Immune tolerance is important for normal physiology. (wikipedia.org)
  • Burnet and Medawar were ultimately credited for "the discovery of acquired immune tolerance" and shared the Nobel Prize in Physiology or Medicine in 1960. (wikipedia.org)
  • Though some pathogens can evolve to become less virulent in host-pathogen coevolution, tolerance does not refer to the change in the pathogen but can be used to describe the changes in host physiology. (wikipedia.org)
  • Regulatory T cells and immune tolerance in the intestine. (ox.ac.uk)
  • Here, we introduce the "cellular ratio of immune tolerance" (immunoCRIT) as defined by the ratio of regulatory T cells to total T lymphocytes. (ox.ac.uk)
  • Tolerance is classified into central tolerance or peripheral tolerance depending on where the state is originally induced-in the thymus and bone marrow (central) or in other tissues and lymph nodes (peripheral). (wikipedia.org)
  • Peripheral tolerance evolved to counteract autoantigen-recognizing T or B cells that escape central tolerance. (frontiersin.org)
  • Peripheral tolerance occurs in the secondary lymphoid organs (e.g. spleen, lymph nodes, and mucosal/gut associated lymphoid tissues) and peripheral tissues. (frontiersin.org)
  • The high levels of SALSA in AF and the infant intestine suggest a robust and important function for SALSA during the fetal development and in the mucosal innate immune defense of infants. (researchgate.net)
  • Aging also impairs oral tolerance, which may be of central importance for maintaining GI homeostasis. (nih.gov)
  • They aimed to prove that tolerance could be artificially induced. (medscape.com)
  • Trophoblast immune receptors in maternal-fetal tolerance. (bvsalud.org)
  • Hence, triggering immune functions via the TLR axis, but not through those histone modifiers, induced the beneficial phenomenon of ET in MEC. (uni-muenchen.de)
  • However, these discoveries, and the host of allograft experiments and observations of twin chimerism they inspired, were seminal for the theories of immune tolerance formulated by Sir Frank McFarlane Burnet and Frank Fenner, who were the first to propose the deletion of self-reactive lymphocytes to establish tolerance, now termed clonal deletion. (wikipedia.org)
  • Special care was taken to overcome the " hard" barriers of allo- or xeno-combinations by reducing the "split tolerance" produced through the clonal destruction mechanism. (nih.gov)