Germinal Center: The activated center of a lymphoid follicle in secondary lymphoid tissue where B-LYMPHOCYTES are stimulated by antigens and helper T cells (T-LYMPHOCYTES, HELPER-INDUCER) are stimulated to generate memory cells.B-Lymphocytes: 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.Dendritic Cells, Follicular: Non-hematopoietic cells, with extensive dendritic processes, found in the primary and secondary follicles of lymphoid tissue (the B cell zones). They are different from conventional DENDRITIC CELLS associated with T-CELLS. They are derived from MESENCHYMAL STEM CELLS and are negative for class II MHC antigen and do not process or present antigen like the conventional dendritic cells do. Instead, follicular dendritic cells have FC RECEPTORS and C3B RECEPTORS that hold antigen in the form of ANTIGEN-ANTIBODY COMPLEXES on their surfaces for long periods for recognition by B-CELLS.Palatine Tonsil: A round-to-oval mass of lymphoid tissue embedded in the lateral wall of the PHARYNX. There is one on each side of the oropharynx in the fauces between the anterior and posterior pillars of the SOFT PALATE.Receptors, CXCR5: CXCR receptors isolated initially from BURKITT LYMPHOMA cells. CXCR5 receptors are expressed on mature, recirculating B-LYMPHOCYTES and are specific for CHEMOKINE CXCL13.B-Lymphocyte Subsets: A classification of B-lymphocytes based on structurally or functionally different populations of cells.Antigens: Substances that are recognized by the immune system and induce an immune reaction.Somatic Hypermutation, Immunoglobulin: A programmed mutation process whereby changes are introduced to the nucleotide sequence of immunoglobulin gene DNA during development.Phenylacetates: Derivatives of phenylacetic acid. Included under this heading are a variety of acid forms, salts, esters, and amides that contain the benzeneacetic acid structure. Note that this class of compounds should not be confused with derivatives of phenyl acetate, which contain the PHENOL ester of ACETIC ACID.Antigenic Modulation: Loss of detectable antigen from the surface of a cell after incubation with antibodies. This is one method in which some tumors escape detection by the immune system. Antigenic modulation of target antigens also reduces the therapeutic effectiveness of treatment by monoclonal antibodies.Immunoglobulin Class Switching: Gene rearrangement of the B-lymphocyte which results in a substitution in the type of heavy-chain constant region that is expressed. This allows the effector response to change while the antigen binding specificity (variable region) remains the same. The majority of class switching occurs by a DNA recombination event but it also can take place at the level of RNA processing.Lymphocyte Activation: 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.NitrophenolsT-Lymphocytes: 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.Spleen: An encapsulated lymphatic organ through which venous blood filters.Inducible T-Cell Co-Stimulator Protein: A costimulatory receptor that is specific for INDUCIBLE T-CELL CO-STIMULATOR LIGAND. The receptor is associated with a diverse array of immunologically-related effects including the increased synthesis of INTERLEUKIN 10 in REGULATORY T-LYMPHOCYTES and the induction of PERIPHERAL TOLERANCE.Mice, Inbred C57BLPlasma Cells: Specialized forms of antibody-producing B-LYMPHOCYTES. They synthesize and secrete immunoglobulin. They are found only in lymphoid organs and at sites of immune responses and normally do not circulate in the blood or lymph. (Rosen et al., Dictionary of Immunology, 1989, p169 & Abbas et al., Cellular and Molecular Immunology, 2d ed, p20)Antigens, Bacterial: Substances elaborated by bacteria that have antigenic activity.Antigen Presentation: 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)Immunologic Memory: 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.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.Antigen-Presenting Cells: 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.Antibody Affinity: A measure of the binding strength between antibody and a simple hapten or antigen determinant. It depends on the closeness of stereochemical fit between antibody combining sites and antigen determinants, on the size of the area of contact between them, and on the distribution of charged and hydrophobic groups. It includes the concept of "avidity," which refers to the strength of the antigen-antibody bond after formation of reversible complexes.Histocompatibility Antigens Class II: Large, transmembrane, non-covalently linked glycoproteins (alpha and beta). Both chains can be polymorphic although there is more structural variation in the beta chains. The class II antigens in humans are called HLA-D ANTIGENS and are coded by a gene on chromosome 6. In mice, two genes named IA and IE on chromosome 17 code for the H-2 antigens. The antigens are found on B-lymphocytes, macrophages, epidermal cells, and sperm and are thought to mediate the competence of and cellular cooperation in the immune response. The term IA antigens used to refer only to the proteins encoded by the IA genes in the mouse, but is now used as a generic term for any class II histocompatibility antigen.Mice, Inbred BALB CAntibody Formation: The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.Antigens, Neoplasm: 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.Antigens, Surface: 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.Dendritic Cells: 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).Immunoglobulin G: The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.Mice, Knockout: 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.Antigens, Viral: Substances elaborated by viruses that have antigenic activity.Mice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.Antigens, CD: 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.Lymph Nodes: They are oval or bean shaped bodies (1 - 30 mm in diameter) located along the lymphatic system.HLA-DR Antigens: A subclass of HLA-D antigens that consist of alpha and beta chains. The inheritance of HLA-DR antigens differs from that of the HLA-DQ ANTIGENS and HLA-DP ANTIGENS.Receptors, Antigen, B-Cell: 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.Proto-Oncogene Proteins c-bcl-6: A DNA-binding protein that represses GENETIC TRANSCRIPTION of target genes by recruiting HISTONE DEACETYLASES. Aberrant Blc-6 expression is associated with certain types of human B-CELL LYMPHOMA.Flow Cytometry: 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.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Lymphoid Tissue: 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.Antigens, Protozoan: Any part or derivative of any protozoan that elicits immunity; malaria (Plasmodium) and trypanosome antigens are presently the most frequently encountered.Molecular Sequence Data: 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.Lymphoma, B-Cell: A group of heterogeneous lymphoid tumors generally expressing one or more B-cell antigens or representing malignant transformations of B-lymphocytes.Histocompatibility Antigens Class I: 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, Polyomavirus Transforming: Polyomavirus antigens which cause infection and cellular transformation. The large T antigen is necessary for the initiation of viral DNA synthesis, repression of transcription of the early region and is responsible in conjunction with the middle T antigen for the transformation of primary cells. Small T antigen is necessary for the completion of the productive infection cycle.Antigens, CD40: A member of the tumor necrosis factor receptor superfamily with specificity for CD40 LIGAND. It is found on mature B-LYMPHOCYTES and some EPITHELIAL CELLS, lymphoid DENDRITIC CELLS. Evidence suggests that CD40-dependent activation of B-cells is important for generation of memory B-cells within the germinal centers. Mutations of the gene for CD40 antigen result in HYPER-IGM IMMUNODEFICIENCY SYNDROME, TYPE 3. Signaling of the receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.Lymphoma, Large B-Cell, Diffuse: Malignant lymphoma composed of large B lymphoid cells whose nuclear size can exceed normal macrophage nuclei, or more than twice the size of a normal lymphocyte. The pattern is predominantly diffuse. Most of these lymphomas represent the malignant counterpart of B-lymphocytes at midstage in the process of differentiation.Cells, Cultured: 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.HLA Antigens: 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, CD80: 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.Gene Rearrangement, B-Lymphocyte: Ordered rearrangement of B-lymphocyte variable gene regions coding for the IMMUNOGLOBULIN CHAINS, thereby contributing to antibody diversity. It occurs during the differentiation of the IMMATURE B-LYMPHOCYTES.Antigens, Fungal: Substances of fungal origin that have antigenic activity.Chemokine CXCL13: A CXC chemokine that is chemotactic for B-LYMPHOCYTES. It has specificity for CXCR5 RECEPTORS.Antigens, T-Independent: Antigens which may directly stimulate B lymphocytes without the cooperation of T lymphocytes.Mucocele: A retention cyst of the salivary gland, lacrimal sac, paranasal sinuses, appendix, or gallbladder. (Stedman, 26th ed)Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Immunoglobulin Variable Region: That region of the immunoglobulin molecule that varies in its amino acid sequence and composition, and comprises the binding site for a specific antigen. It is located at the N-terminus of the Fab fragment of the immunoglobulin. It includes hypervariable regions (COMPLEMENTARITY DETERMINING REGIONS) and framework regions.CD4-Positive T-Lymphocytes: 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.Immunoglobulin M: A class of immunoglobulin bearing mu chains (IMMUNOGLOBULIN MU-CHAINS). IgM can fix COMPLEMENT. The name comes from its high molecular weight and originally being called a macroglobulin.Antigens, Helminth: Any part or derivative of a helminth that elicits an immune reaction. The most commonly seen helminth antigens are those of the schistosomes.Genes, Immunoglobulin: Genes encoding the different subunits of the IMMUNOGLOBULINS, for example the IMMUNOGLOBULIN LIGHT CHAIN GENES and the IMMUNOGLOBULIN HEAVY CHAIN GENES. The heavy and light immunoglobulin genes are present as gene segments in the germline cells. The completed genes are created when the segments are shuffled and assembled (B-LYMPHOCYTE GENE REARRANGEMENT) during B-LYMPHOCYTE maturation. The gene segments of the human light and heavy chain germline genes are symbolized V (variable), J (joining) and C (constant). The heavy chain germline genes have an additional segment D (diversity).H-2 Antigens: The major group of transplantation antigens in the mouse.Ovalbumin: An albumin obtained from the white of eggs. It is a member of the serpin superfamily.HLA-D Antigens: Human immune-response or Class II antigens found mainly, but not exclusively, on B-lymphocytes and produced from genes of the HLA-D locus. They are extremely polymorphic families of glycopeptides, each consisting of two chains, alpha and beta. This group of antigens includes the -DR, -DQ and -DP designations, of which HLA-DR is most studied; some of these glycoproteins are associated with certain diseases, possibly of immune etiology.Immunoglobulin Heavy Chains: The largest of polypeptide chains comprising immunoglobulins. They contain 450 to 600 amino acid residues per chain, and have molecular weights of 51-72 kDa.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Antigens, CD86: 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.Amino Acid Sequence: 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.Antigens, CD1: Glycoproteins expressed on cortical thymocytes and on some dendritic cells and B-cells. Their structure is similar to that of MHC Class I and their function has been postulated as similar also. CD1 antigens are highly specific markers for human LANGERHANS CELLS.Immunization: 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).Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Carcinoembryonic Antigen: A glycoprotein that is secreted into the luminal surface of the epithelia in the gastrointestinal tract. It is found in the feces and pancreaticobiliary secretions and is used to monitor the response to colon cancer treatment.Receptors, Antigen, T-Cell: 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.Genes, MHC Class II: Genetic loci in the vertebrate major histocompatibility complex that encode polymorphic products which control the immune response to specific antigens. The genes are found in the HLA-D region in humans and in the I region in mice.Antigens, Viral, Tumor: Those proteins recognized by antibodies from serum of animals bearing tumors induced by viruses; these proteins are presumably coded for by the nucleic acids of the same viruses that caused the neoplastic transformation.Lymphoma, Follicular: Malignant lymphoma in which the lymphomatous cells are clustered into identifiable nodules within the LYMPH NODES. The nodules resemble to some extent the GERMINAL CENTER of lymph node follicles and most likely represent neoplastic proliferation of lymph node-derived follicular center B-LYMPHOCYTES.T-Lymphocytes, Helper-Inducer: 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.Panuveitis: Inflammation in which both the anterior and posterior segments of the uvea are involved and a specific focus is not apparent. It is often severe and extensive and a serious threat to vision. Causes include systemic diseases such as tuberculosis, sarcoidosis, and syphilis, as well as malignancies. The intermediate segment of the eye is not involved.Peyer's Patches: Lymphoid tissue on the mucosa of the small intestine.Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Macrophages: 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.)Epitopes: Sites on an antigen that interact with specific antibodies.Antigens, Differentiation: 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.Enzyme-Linked Immunosorbent Assay: 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.Immunoglobulin D: An immunoglobulin which accounts for less than 1% of plasma immunoglobulin. It is found on the membrane of many circulating B LYMPHOCYTES.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Haptens: Small antigenic determinants capable of eliciting an immune response only when coupled to a carrier. Haptens bind to antibodies but by themselves cannot elicit an antibody response.Histocompatibility Antigens: A group of antigens that includes both the major and minor histocompatibility antigens. The former are genetically determined by the major histocompatibility complex. They determine tissue type for transplantation and cause allograft rejections. The latter are systems of allelic alloantigens that can cause weak transplant rejection.Peanut Agglutinin: Lectin purified from peanuts (ARACHIS HYPOGAEA). It binds to poorly differentiated cells and terminally differentiated cells and is used in cell separation techniques.Immunoenzyme Techniques: Immunologic techniques based on the use of: (1) enzyme-antibody conjugates; (2) enzyme-antigen conjugates; (3) antienzyme antibody followed by its homologous enzyme; or (4) enzyme-antienzyme complexes. These are used histologically for visualizing or labeling tissue specimens.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Central Cord Syndrome: A syndrome associated with traumatic injury to the cervical or upper thoracic regions of the spinal cord characterized by weakness in the arms with relative sparing of the legs and variable sensory loss. This condition is associated with ischemia, hemorrhage, or necrosis involving the central portions of the spinal cord. Corticospinal fibers destined for the legs are spared due to their more external location in the spinal cord. This clinical pattern may emerge during recovery from spinal shock. Deficits may be transient or permanent.Proliferating Cell Nuclear Antigen: Nuclear antigen with a role in DNA synthesis, DNA repair, and cell cycle progression. PCNA is required for the coordinated synthesis of both leading and lagging strands at the replication fork during DNA replication. PCNA expression correlates with the proliferation activity of several malignant and non-malignant cell types.Antigens, CD11c: An integrin alpha subunit of approximately 150-kDa molecular weight. It is expressed at high levels on monocytes and combines with CD18 ANTIGEN to form the cell surface receptor INTEGRIN ALPHAXBETA2. The subunit contains a conserved I-domain which is characteristic of several of alpha integrins.Immune Tolerance: 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.Cytidine Deaminase: An enzyme that catalyzes the deamination of cytidine, forming uridine. EC 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.Prostate-Specific Antigen: A glycoprotein that is a kallikrein-like serine proteinase and an esterase, produced by epithelial cells of both normal and malignant prostate tissue. It is an important marker for the diagnosis of prostate cancer.Fluorescent Antibody Technique: Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Antigens, CD3: 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).O Antigens: The lipopolysaccharide-protein somatic antigens, usually from gram-negative bacteria, important in the serological classification of enteric bacilli. The O-specific chains determine the specificity of the O antigens of a given serotype. O antigens are the immunodominant part of the lipopolysaccharide molecule in the intact bacterial cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)Clone Cells: A group of genetically identical cells all descended from a single common ancestral cell by mitosis in eukaryotes or by binary fission in prokaryotes. Clone cells also include populations of recombinant DNA molecules all carrying the same inserted sequence. (From King & Stansfield, Dictionary of Genetics, 4th ed)Antigens, CD45: High-molecular weight glycoproteins uniquely expressed on the surface of LEUKOCYTES and their hemopoietic progenitors. They contain a cytoplasmic protein tyrosine phosphatase activity which plays a role in intracellular signaling from the CELL SURFACE RECEPTORS. The CD45 antigens occur as multiple isoforms that result from alternative mRNA splicing and differential usage of three exons.Antibody Specificity: The property of antibodies which enables them to react with some ANTIGENIC DETERMINANTS and not with others. Specificity is dependent on chemical composition, physical forces, and molecular structure at the binding site.Antigens, CD19: Differentiation antigens expressed on B-lymphocytes and B-cell precursors. They are involved in regulation of B-cell proliferation.Lymphocytes: 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.Antigens, CD15: A trisaccharide antigen expressed on glycolipids and many cell-surface glycoproteins. In the blood the antigen is found on the surface of NEUTROPHILS; EOSINOPHILS; and MONOCYTES. In addition, CD15 antigen is a stage-specific embryonic antigen.HemocyaninBiopsy: Removal and pathologic examination of specimens in the form of small pieces of tissue from the living body.Antigens, CD8: Differentiation antigens found on thymocytes and on cytotoxic and suppressor T-lymphocytes. CD8 antigens are members of the immunoglobulin supergene family and are associative recognition elements in MHC (Major Histocompatibility Complex) Class I-restricted interactions.HLA-A2 Antigen: A specific HLA-A surface antigen subtype. Members of this subtype contain alpha chains that are encoded by the HLA-A*02 allele family.Immunoglobulins: Multi-subunit proteins which function in IMMUNITY. They are produced by B LYMPHOCYTES from the IMMUNOGLOBULIN GENES. They are comprised of two heavy (IMMUNOGLOBULIN HEAVY CHAINS) and two light chains (IMMUNOGLOBULIN LIGHT CHAINS) with additional ancillary polypeptide chains depending on their isoforms. The variety of isoforms include monomeric or polymeric forms, and transmembrane forms (B-CELL ANTIGEN RECEPTORS) or secreted forms (ANTIBODIES). They are divided by the amino acid sequence of their heavy chains into five classes (IMMUNOGLOBULIN A; IMMUNOGLOBULIN D; IMMUNOGLOBULIN E; IMMUNOGLOBULIN G; IMMUNOGLOBULIN M) and various subclasses.Antigens, Tumor-Associated, Carbohydrate: Carbohydrate antigens expressed by malignant tissue. They are useful as tumor markers and are measured in the serum by means of a radioimmunoassay employing monoclonal antibodies.Models, Immunological: 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.Lymphocyte Culture Test, Mixed: 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.Neprilysin: Enzyme that is a major constituent of kidney brush-border membranes and is also present to a lesser degree in the brain and other tissues. It preferentially catalyzes cleavage at the amino group of hydrophobic residues of the B-chain of insulin as well as opioid peptides and other biologically active peptides. The enzyme is inhibited primarily by EDTA, phosphoramidon, and thiorphan and is reactivated by zinc. Neprilysin is identical to common acute lymphoblastic leukemia antigen (CALLA Antigen), an important marker in the diagnosis of human acute lymphocytic leukemia. There is no relationship with CALLA PLANT.Mice, Inbred C3HAntigen-Antibody Complex: 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.Lymphocyte Cooperation: T-cell enhancement of the B-cell response to thymic-dependent antigens.Antigens, CD4: 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.Antibodies: 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).Pseudolymphoma: A group of disorders having a benign course but exhibiting clinical and histological features suggestive of malignant lymphoma. Pseudolymphoma is characterized by a benign infiltration of lymphoid cells or histiocytes which microscopically resembles a malignant lymphoma. (From Dorland, 28th ed & Stedman, 26th ed)Antigens, CD27: A member of the tumor necrosis factor receptor superfamily found on most T-LYMPHOCYTES. Activation of the receptor by CD70 ANTIGEN results in the increased proliferation of CD4-POSITIVE T-LYMPHOCYTES and CD8-POSITIVE T-LYMPHOCYTES. Signaling by the activated receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.CD40 Ligand: 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.Glucose Transport Proteins, Facilitative: A family of monosaccharide transport proteins characterized by 12 membrane spanning helices. They facilitate passive diffusion of GLUCOSE across the CELL MEMBRANE.gamma-Globulins: Serum globulins that migrate to the gamma region (most positively charged) upon ELECTROPHORESIS. At one time, gamma-globulins came to be used as a synonym for immunoglobulins since most immunoglobulins are gamma globulins and conversely most gamma globulins are immunoglobulins. But since some immunoglobulins exhibit an alpha or beta electrophoretic mobility, that usage is in decline.Cytokines: 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.Cross Reactions: Serological reactions in which an antiserum against one antigen reacts with a non-identical but closely related antigen.Hepatitis B Surface Antigens: Those hepatitis B antigens found on the surface of the Dane particle and on the 20 nm spherical and tubular particles. Several subspecificities of the surface antigen are known. These were formerly called the Australia antigen.Cell Movement: The movement of cells from one location to another. Distinguish from CYTOKINESIS which is the process of dividing the CYTOPLASM of a cell.Blood Group Antigens: Sets of cell surface antigens located on BLOOD CELLS. They are usually membrane GLYCOPROTEINS or GLYCOLIPIDS that are antigenically distinguished by their carbohydrate moieties.Signal Transduction: 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.Interferon Regulatory Factors: A family of transcription factors that share an N-terminal HELIX-TURN-HELIX MOTIF and bind INTERFERON-inducible promoters to control GENE expression. IRF proteins bind specific DNA sequences such as interferon-stimulated response elements, interferon regulatory elements, and the interferon consensus sequence.Immunity, Humoral: Antibody-mediated immune response. Humoral immunity is brought about by ANTIBODY FORMATION, resulting from TH2 CELLS activating B-LYMPHOCYTES, followed by COMPLEMENT ACTIVATION.Antigen-Antibody Reactions: The processes triggered by interactions of ANTIBODIES with their ANTIGENS.Antibody-Producing Cells: Cells of the lymphoid series that can react with antigen to produce specific cell products called antibodies. Various cell subpopulations, often B-lymphocytes, can be defined, based on the different classes of immunoglobulins that they synthesize.Burkitt Lymphoma: A form of undifferentiated malignant LYMPHOMA usually found in central Africa, but also reported in other parts of the world. It is commonly manifested as a large osteolytic lesion in the jaw or as an abdominal mass. B-cell antigens are expressed on the immature cells that make up the tumor in virtually all cases of Burkitt lymphoma. The Epstein-Barr virus (HERPESVIRUS 4, HUMAN) has been isolated from Burkitt lymphoma cases in Africa and it is implicated as the causative agent in these cases; however, most non-African cases are EBV-negative.HLA-A Antigens: Polymorphic class I human histocompatibility (HLA) surface antigens present on almost all nucleated cells. At least 20 antigens have been identified which are encoded by the A locus of multiple alleles on chromosome 6. They serve as targets for T-cell cytolytic responses and are involved with acceptance or rejection of tissue/organ grafts.Receptors, Complement 3d: Molecular sites on or in B-lymphocytes, follicular dendritic cells, lymphoid cells, and epithelial cells that recognize and combine with COMPLEMENT C3D. Human complement receptor 2 (CR2) serves as a receptor for both C3dg and the gp350/220 glycoprotein of HERPESVIRUS 4, HUMAN, and binds the monoclonal antibody OKB7, which blocks binding of both ligands to the receptor.Immune Sera: 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.Gene Rearrangement, B-Lymphocyte, Heavy Chain: Ordered rearrangement of B-lymphocyte variable gene regions of the IMMUNOGLOBULIN HEAVY CHAINS, thereby contributing to antibody diversity. It occurs during the first stage of differentiation of the IMMATURE B-LYMPHOCYTES.Reed-Sternberg Cells: Large cells, usually multinucleate, whose presence is a common histologic characteristic of classical HODGKIN DISEASE.Thymus Gland: 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.Antigens, CD20: Unglycosylated phosphoproteins expressed only on B-cells. They are regulators of transmembrane Ca2+ conductance and thought to play a role in B-cell activation and proliferation.Autoantibodies: Antibodies that react with self-antigens (AUTOANTIGENS) of the organism that produced them.Langerhans Cells: Recirculating, dendritic, antigen-presenting cells containing characteristic racket-shaped granules (Birbeck granules). They are found principally in the stratum spinosum of the EPIDERMIS and are rich in Class II MAJOR HISTOCOMPATIBILITY COMPLEX molecules. Langerhans cells were the first dendritic cell to be described and have been a model of study for other dendritic cells (DCs), especially other migrating DCs such as dermal DCs and INTERSTITIAL DENDRITIC CELLS.DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Child Day Care Centers: Facilities which provide care for pre-school and school-age children.Lymphoma: A general term for various neoplastic diseases of the lymphoid tissue.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Cysts: Any fluid-filled closed cavity or sac that is lined by an EPITHELIUM. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues.Abdominal Pain: Sensation of discomfort, distress, or agony in the abdominal region.Receptors, Interleukin-21: Cell surface receptors for interleukin 21. They are heterodimeric proteins found on DENDRITIC CELLS and LYMPHOCYTES that consist of the INTERLEUKIN-21 RECEPTOR ALPHA SUBUNIT and the CYTOKINE RECEPTOR COMMON BETA SUBUNIT.Facial Hemiatrophy: A syndrome characterized by slowly progressive unilateral atrophy of facial subcutaneous fat, muscle tissue, skin, cartilage, and bone. The condition typically progresses over a period of 2-10 years and then stabilizes.Antigens, CD38: A bifunctional enzyme that catalyzes the synthesis and HYDROLYSIS of CYCLIC ADP-RIBOSE (cADPR) from NAD+ to ADP-RIBOSE. It is a cell surface molecule which is predominantly expressed on LYMPHOID CELLS and MYELOID CELLS.Hodgkin Disease: A malignant disease characterized by progressive enlargement of the lymph nodes, spleen, and general lymphoid tissue. In the classical variant, giant usually multinucleate Hodgkin's and REED-STERNBERG CELLS are present; in the nodular lymphocyte predominant variant, lymphocytic and histiocytic cells are seen.Receptors, Antigen: Molecules on the surface of B- and T-lymphocytes that recognize and combine with specific antigens.Hepatitis B Antigens: Antigens of the virion of the HEPATITIS B VIRUS or the Dane particle, its surface (HEPATITIS B SURFACE ANTIGENS), core (HEPATITIS B CORE ANTIGENS), and other associated antigens, including the HEPATITIS B E ANTIGENS.Monocytes: Large, phagocytic mononuclear leukocytes produced in the vertebrate BONE MARROW and released into the BLOOD; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles.Antibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Prognosis: A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations.Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Bursa of Fabricius: An epithelial outgrowth of the cloaca in birds similar to the thymus in mammals. It atrophies within 6 months after birth and remains as a fibrous remnant in adult birds. It is composed of lymphoid tissue and prior to involution, is the site of B-lymphocyte maturation.Neoplasm Proteins: Proteins whose abnormal expression (gain or loss) are associated with the development, growth, or progression of NEOPLASMS. Some neoplasm proteins are tumor antigens (ANTIGENS, NEOPLASM), i.e. they induce an immune reaction to their tumor. Many neoplasm proteins have been characterized and are used as tumor markers (BIOMARKERS, TUMOR) when they are detectable in cells and body fluids as monitors for the presence or growth of tumors. Abnormal expression of ONCOGENE PROTEINS is involved in neoplastic transformation, whereas the loss of expression of TUMOR SUPPRESSOR PROTEINS is involved with the loss of growth control and progression of the neoplasm.Chromosomes, Human, Pair 14: A specific pair of GROUP D CHROMOSOMES of the human chromosome classification.Acute Disease: Disease having a short and relatively severe course.Fatal Outcome: Death resulting from the presence of a disease in an individual, as shown by a single case report or a limited number of patients. This should be differentiated from DEATH, the physiological cessation of life and from MORTALITY, an epidemiological or statistical concept.T-Lymphocyte Subsets: A classification of T-lymphocytes, especially into helper/inducer, suppressor/effector, and cytotoxic subsets, based on structurally or functionally different populations of cells.Antigens, CD95: A tumor necrosis factor receptor subtype found in a variety of tissues and on activated LYMPHOCYTES. It has specificity for FAS LIGAND and plays a role in regulation of peripheral immune responses and APOPTOSIS. Multiple isoforms of the protein exist due to multiple ALTERNATIVE SPLICING. The activated receptor signals via a conserved death domain that associates with specific TNF RECEPTOR-ASSOCIATED FACTORS in the CYTOPLASM.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.Radiography, Thoracic: X-ray visualization of the chest and organs of the thoracic cavity. It is not restricted to visualization of the lungs.Ki-67 Antigen: A CELL CYCLE and tumor growth marker which can be readily detected using IMMUNOCYTOCHEMISTRY methods. Ki-67 is a nuclear antigen present only in the nuclei of cycling cells.Autoantigens: Endogenous tissue constituents that have the ability to interact with AUTOANTIBODIES and cause an immune response.Immunoglobulin A: Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory IgA (IMMUNOGLOBULIN A, SECRETORY) is the main immunoglobulin in secretions.Epstein-Barr Virus Nuclear Antigens: Nuclear antigens encoded by VIRAL GENES found in HUMAN HERPESVIRUS 4. At least six nuclear antigens have been identified.Antigens, CD5: Glycoproteins expressed on all mature T-cells, thymocytes, and a subset of mature B-cells. Antibodies specific for CD5 can enhance T-cell receptor-mediated T-cell activation. The B-cell-specific molecule CD72 is a natural ligand for CD5. (From Abbas et al., Cellular and Molecular Immunology, 2d ed, p156)Immunoblastic Lymphadenopathy: A disorder characterized by proliferation of arborizing small vessels, prominent immunoblastic proliferations and amorphous acidophilic interstitial material. Clinical manifestations include fever, sweats, weight loss, generalized lymphadenopathy and frequently hepatosplenomegaly.Lymphatic Diseases: Diseases of LYMPH; LYMPH NODES; or LYMPHATIC VESSELS.Mice, Inbred Strains: 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.HLA-B Antigens: Class I human histocompatibility (HLA) surface antigens encoded by more than 30 detectable alleles on locus B of the HLA complex, the most polymorphic of all the HLA specificities. Several of these antigens (e.g., HLA-B27, -B7, -B8) are strongly associated with predisposition to rheumatoid and other autoimmune disorders. Like other class I HLA determinants, they are involved in the cellular immune reactivity of cytolytic T lymphocytes.Autoimmunity: Process whereby the immune system reacts against the body's own tissues. Autoimmunity may produce or be caused by AUTOIMMUNE DISEASES.Appendicitis: Acute inflammation of the APPENDIX. Acute appendicitis is classified as simple, gangrenous, or perforated.Apoptosis: 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.Diagnostic Errors: Incorrect diagnoses after clinical examination or technical diagnostic procedures.Cell SeparationLymphotoxin-beta: A membrane-bound tumor necrosis family member found primarily on LYMPHOCYTES. It can form a heterotrimer (LYMPHOTOXIN ALPHA1, BETA2 HETEROTRIMER) with the soluble ligand LYMPHOTOXIN-ALPHA and anchor it to the cell surface. The membrane-bound complex is specific for the LYMPHOTOXIN BETA receptor.Phagocytosis: The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).RNA, Messenger: 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.Gene Expression Regulation: 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.Adoptive Transfer: 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).Epitopes, B-Lymphocyte: Antigenic determinants recognized and bound by the B-cell receptor. Epitopes recognized by the B-cell receptor are located on the surface of the antigen.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Immunity, Cellular: 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.Tumor Cells, Cultured: Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.
... of lymphoid follicles and have an integral role in regulation of the germinal center reaction and present antigens to B cells. ... Cyclophosphamide slows or stops cell growth cells. It targets cells that are rapidly dividing which include cancer cells that ... Kosco, Marie H.; Gray, David (1992). "Signals Involved in Germinal Center Reactions". Immunological Reviews. 126: 63-76. doi: ... Follicular dendritic cells are localized in germinal centers ... a leukocyte common antigen, and CD15, a monocyte common antigen ...
... indicating that they have been generated through a germinal centre reaction to become memory cells. Similar to B1 B cells, MZ B ... marginal zone B-cells will fail to develop while B-1 cells will still be present. MZ B-cells are the only B-cells dependent on ... The MZ B cells are especially well positioned as a first line of defense against systemic blood-borne antigens that enter the ... B cells and B1 B cells. In humans the splenic marginal zone B cells have evidence of somatic hypermutation in their ...
... class-switching during germinal centre reaction and provide different effector functions in response to specific antigens. IgG ... enzyme and only occurs after the B cell binds an antigen through its B cell receptor, and is further activated through ... IgE antibodies are present at lowest concentrations in peripheral blood but constitute the main antibody class in allergic ... As IgM antibodies are expressed early in a B cell response, they are rarely highly mutated and have broad antigen reactivity ...
T helper cells requires the B7 molecule present on the antigen presenting cell to bind with CD28 molecule present on the T cell ... germinal centers of lymph nodes and clonal selection of B cells, see Lymph node, Germinal center, and Clonal selection. ... Increased chances of autoimmune reactions[edit]. For more details on autoimmunity, see Autoimmunity. ... Activation of the T helper cells by antigen-presenting cells.. *Costimulation of the B cell by activated T cell resulting in ...
... memory T helper cells and B cells persist at a fairly constant level in germinal centers, undergoing cell division at a slow to ... People can also measure the active B and T cell activity against that antigen after a certain amount of time that the primary ... If a patient receives a booster dose but already has a high level of antibody, then a reaction called an Arthus reaction could ... However, in places where polio is still present, following up an OPV primary dose with an IPV booster may help eradicate the ...
B cells can present antigens to a specialized group of helper T cells called TFH cells. If an activated TFH cell recognizes the ... As a result of this stimulation, the B cell can undergo rapid cellular division to form a germinal center where antibody ... This inflammatory reaction in endothelial cells promotes recruitment of leukocytes to lesions and may potentially promote ... NK cells, B lymphocytes, as well as non-haematopoietic cells (smooth muscle cells, endothelial cells, and epithelial cells). ...
... due to CD5 positive antigen-naive pregerminal center B-cell within the mantle zone that surrounds normal germinal center ... Chest, abdominal, and pelvic CT scans are routinely performed.[citation needed] Since mantle cell lymphoma may present a ... Polymerase chain reaction (PCR) and CER3 clonotypic primers are additional methods, but are less often used.[citation needed] ... MCL cell types can aid in prognosis in a subjective way. Blastic is a larger cell type. Diffuse is spread through the node. ...
B cells acquire antigen from follicular dendritic cells (FDCs) and in turn present it to cognate CD4+ TFH cells at the border ... in part through these germinal center reactions, can gradually better recognize antigens over time. The morphology of GCs is ... cells in the presence of follicular dendritic cells (FDCs). Germinal centers are an important part of the B cell humoral immune ... Interactions with T cells are also believed to prevent the generation of autoreactive germinal center B cells. At some unclear ...
... can also be demonstrated in germinal centre B-cells using immunohistochemistry, but it is not present in the resting cells ... The antigen is then transferred from CD23+ B cells to CD11c+ antigen presenting cells. The CD11c+ cells in turn present the ... International Journal of Tissue Reactions. 14 (3): 121-30. PMID 1446976. Sugie K, Kawakami T, Maeda Y, Kawabe T, Uchida A, ... CD23a is present on follicular B cells, whereas CD23b requires IL-4 to be expressed on T-cells, monocytes, Langerhans cells, ...
This material may present a threat to the tolerization of B cells and T cells. Dendritic cells in the germinal center may ... These stimuli begin a reaction that leads to destruction of other cells in the body and exposure of their DNA, histones, and ... Autoreactive B cells, maturated coincidentally, normally do not receive survival signals by antigen planted on follicular ... large phagocytic cells in the germinal centers of secondary lymph nodes - express CD68 protein. These cells normally engulf B ...
... including poorly demarcated reactive germinal centers, clusters of monocytoid B cells, and scattered epithelioid histiocytes. ... Tissue cysts are rarely present in buffalo meat or beef, and meat from these animals is considered to be low-risk for harboring ... T. gondii may also be detected in blood, amniotic fluid, or cerebrospinal fluid by using polymerase chain reaction. T. gondii ... In the first response to infection, toxoplasma-specific IgG has a low affinity for the toxoplasma antigen; in the following ...
Plasma cells typically result from the germinal center reaction from T cell-dependent activation of B cells, however they can ... Additionally, B cells present antigen (they are also classified as professional antigen-presenting cells (APCs)) and secrete ... Antigens that activate B cells with the help of T-cell are known as T cell-dependent (TD) antigens and include foreign proteins ... At the SLO, B cell activation begins when the B cell binds to an antigen via its BCR. Of the three B cell subsets, FO B cells ...
Anergic cells will not respond to any antigen in the future, even if both signals are present later on. These cells are ... Absence of CD154 also stops the formation of germinal centers and therefore prohibiting antibody affinity maturation, an ... Tuberculin reaction or Type 1 diabetes belong to this category of autoimmunity. Th2 helper cells are the host immunity ... For example, when an antigen-presenting cell expresses an antigen on MHC class II, a CD4+ cell will aid those cells through a ...
... which may develop a germinal center when challenged with an antigen, and the deeper paracortex mainly consists of the T cells. ... They present the antigen to T cells and, if there is a T cell with the appropriate T cell receptor, it will be activated. B ... Lymph nodes may become enlarged due to an infection, tumor, autoimmune disease, drug reactions, or to leukemia. Swollen lymph ... Other B cells will internalize the antigen and present it to Follicular helper T cells on the B and T cell zone interface. If a ...
B-cells that have not encountered an antigen are called naive B cells. When naïve B-cells encounter an antigen, one of the ... "Transcriptional analysis of the B cell germinal center reaction". Proceedings of the National Academy of Sciences. 100 (5): ... is present in 45% of GCB DLBCLs but has never been found in ABC DLBCLs. This T(14,18) translocation places the BCL-2 gene close ... Germinal Center B-Cell like (GCB) DLBCLs appear to arise from normal germinal center B cells, while Activated B-cell like (ABC ...
... functional relationship between CD77 and CD19 during germinal center B-cell apoptosis". Journal of Cellular Physiology. 176 (2 ... In fact, it is present on B cells from earliest recognizable B-lineage cells during development to B-cell blasts but is lost on ... As on T cells, several surface molecules form the antigen receptor and form a complex on B lymphocytes. The (almost) B cell- ... Thunberg U, Gidlöf C, Bånghagen M, Sällström JF, Sundström C, Tötterman T (1998). "HpaII polymerase chain reaction restriction ...
Paterson MA, Horvath AJ, Pike RN, Coughlin PB (August 2007). "Molecular characterization of centerin, a germinal centre cell ... "Squamous cell carcinoma antigen 2 is a novel serpin that inhibits the chymotrypsin-like proteinases cathepsin G and mast cell ... The RCL of several serpins from wheat grain and rye contain poly-Q repeat sequences similar to those present in the prolamin ... Wiman B, Collen D (September 1979). "On the mechanism of the reaction between human alpha 2-antiplasmin and plasmin". The ...
Kalled SL (October 2006). "Impact of the BAFF/BR3 axis on B cell survival, germinal center maintenance and antibody production ... The same reduction can be present in the recently defined "Non Celiac Gluten sensitivity" (a reaction to gluten which provokes ... B-cell maturation antigen), all of which have differing binding affinities for it. These receptors are expressed mainly on ... This cytokine is expressed in B cell lineage cells, and acts as a potent B cell activator. It has been also shown to play an ...
It is part of the B cell receptor (BCR), which allows a B cell to detect when a specific antigen is present in the body and ... Or-Guil M, Wittenbrink N, Weiser AA, Schuchhardt J (2007). "Recirculation of germinal center B cells: a multilevel selection ... on the surface of cells could bind specifically to toxins - in a "lock-and-key" interaction - and that this binding reaction is ... B cell activation follows engagement of the cell-bound antibody molecule with an antigen, causing the cell to divide and ...
They present the antigen to T cells and, if there is a T cell with the appropriate T cell receptor, it will be activated.[11] ... these may develop into what is called a germinal centre.[1] The deeper paracortex mainly consists of the T cells.[1] Here the T ... drug reactions, diseases such as amyloidosis and sarcoidosis, or because of lymphoma or leukemia.[14][13] Depending on the ... Other B cells will internalize the antigen and present it to Follicular helper T cells on the B and T cell zone interface. If a ...
Anergic cells will not respond to any antigen in the future, even if both signals are present later on. These cells are ... Absence of CD154 also stops the formation of germinal centers and therefore prohibiting antibody affinity maturation, an ... These reactions all involve IgE antibodies, which require a Th2 response during helper T cell development. Preventive ... For example, when an antigen-presenting cell expresses an antigen on MHC class II, a CD4+ cell will aid those cells through a ...
2004). "Detection of Ectopic B-cell Follicles with Germinal Centers in the Meninges of Patients with Secondary Progressive ... Some special cells present only in the cerebellum, Purkinje cells, have been reported to be part of this problems. Increasing ... August 2008). "EBNA1-specific T cells from patients with multiple sclerosis cross react with myelin antigens and co-produce IFN ... The reactions have been diverse according to the sources of the disease but pathological confirmed MS (damage fulfills all ...
Antigen presenting cells *Dendritic cells. *Langerhans cell. *CFU-DL. *CFU-M *MPS ... Beale LS (1864). "On the Germinal Matter of the Blood, with Remarks upon the Formation of Fibrin". Transactions of the ... The lower volume of plasma also reduces the chances of an adverse transfusion reaction to plasma proteins.[62] Volume reduced ... NETs bind tissue factor, binding the coagulation centres to the location of infection. They also activate the intrinsic ...
germinal center/follicular B cell (Follicular. *Burkitt's. *GCB DLBCL. *Primary cutaneous follicle center lymphoma) ... Cyclical fever: patients may also present with a cyclical high-grade fever known as the Pel-Ebstein fever,[15] or more simply " ... is not routinely used to treat Hodgkin's lymphoma due to the lack of CD20 surface antigens in most cases. The use of rituximab ... Reed-Sternberg cells are usually of B cell origin.[19][20] Although Hodgkin's is now frequently grouped with other B-cell ...
T helper cells requires the B7 molecule present on the antigen presenting cell to bind with CD28 molecule present on the T cell ... is that the B lymphocytes have to compete with each other for signals that promote their survival in the germinal centers. ... it also increases chances of developing certain autoimmune diseases resulting from the reaction of the immune system against ... Antigen presentation. Activation of the T helper cells by antigen-presenting cells. Costimulation of the B cell by activated T ...
A tingible body macrophage is a type of macrophage predominantly found in germinal centers, containing many phagocytized, apoptotic cells in various states of degradation, referred to as tingible bodies (tingible meaning stainable). Tingible body macrophages contain condensed chromatin fragments. It is thought that they may play a role in downregulating the germinal center reaction by the release of prostaglandins and hence a reduced B-cell induction of IL-2. Macrophages that contain debris from ingested lymphocytes are characteristic of a reactive follicular center in benign reactive lymphadenitis. Other accompanying signs of a benign follicular hyperplasia are well developed germinal centers with dark and light zones, in addition to ...
... (FDCS) is an extremely rare neoplasm. While the existence of FDC tumors was predicted by Lennert in 1978, the tumor wasn't fully recognized as its own cancer until 1986 after characterization by Monda et al. It accounts for only 0.4% of soft tissue sarcomas, but has significant recurrent and metastatic potential and is considered an intermediate grade malignancy. The major hurdle in treating FDCS has been misdiagnosis. It is a newly characterized cancer, and because of its similarities in presentation and markers to lymphoma, both Hodgkin and Non-Hodgkin subtypes, diagnosis of FDCS can be difficult. With recent advancements in cancer biology better diagnostic assays and chemotherapeutic agents have been made to more accurately diagnose and treat FDCS.[citation needed] Follicular dendritic cells are localized in germinal centers of lymphoid follicles and have an integral role in regulation of the ...
... (SMZL) is a type of cancer (specifically a lymphoma) made up of B-cells that replace the normal architecture of the white pulp of the spleen. The neoplastic cells are both small lymphocytes and larger, transformed lymphoblasts, and they invade the mantle zone of splenic follicles and erode the marginal zone, ultimately invading the red pulp of the spleen. Frequently, the bone marrow and splenic hilar lymph nodes are involved along with the peripheral blood. The neoplastic cells circulating in the peripheral blood are termed villous lymphocytes due to their characteristic appearance. Under older classification systems, the following names were used: The cell of origin is postulated to be a post-germinal center B-cell with an unknown degree of differentiation. SMZL is a form of cancer known to be associated with Hepatitis C virus infection.[citation needed] Enlargement of the spleen is a ...
ADAM-like, decysin 1 is a protein that in humans is encoded by the ADAMDEC1 gene. This encoded protein is thought to be a secreted protein belonging to the disintegrin metalloproteinase family. Its expression is upregulated during the maturation of dendritic cells. This protein may play an important role in dendritic cell function and their interactions with germinal center T cells. [provided by RefSeq, Jul 2008]. "Entrez Gene: ADAM-like, decysin 1". Retrieved 2014-08-16. Mueller, C. G.; Rissoan, M. C.; Salinas, B; Ait-Yahia, S; Ravel, O; Bridon, J. M.; Briere, F; Lebecque, S; Liu, Y. J. (1997). "Polymerase chain reaction selects a novel disintegrin proteinase from CD40-activated germinal center dendritic cells". The Journal of Experimental Medicine. 186 (5): 655-63. doi:10.1084/jem.186.5.655. PMC 2199019 . ...
... , also called CD40 ligand or CD40L, is a protein that is primarily expressed on activated T cells[5] and is a member of the TNF superfamily of molecules. It binds to CD40 (protein) on antigen-presenting cells (APC), which leads to many effects depending on the target cell type. In total CD40L has three binding partners: CD40, α5β1 integrin and αIIbβ3. CD154 acts as a costimulatory molecule and is particularly important on a subset of T cells called T follicular helper cells (TFH cells).[6] On TFH cells, CD154 promotes B cell maturation and function by engaging CD40 on the B cell surface and therefore facilitating cell-cell communication.[7] A defect in this gene results in an inability to undergo immunoglobulin class switching and is associated with hyper IgM syndrome.[8] Absence of CD154 also stops the formation of germinal ...
... (MCL) is a type of non-Hodgkin's lymphoma (NHL), comprising about 6% of NHL cases. There are only about 15,000 patients presently in the U.S. MCL is a subtype of B-cell lymphoma, due to CD5 positive antigen-naive pregerminal center B-cell within the mantle zone that surrounds normal germinal center follicles. MCL cells generally over-express cyclin D1 due to a t(11:14) chromosomal translocation in the DNA. Specifically, the translocation is at t(11;14)(q13;q32). At diagnosis, patients typically are in their 60s and present to their physician with advanced disease. About half have either fever, night sweats, or unexplained weight loss (over 10% of body weight). Enlarged lymph nodes (for example, a "bump" on the neck, armpits or groin) or splenomegaly are usually present. Bone marrow, liver and GI tract ...
G-protein coupled receptor 183 also known as Epstein-Barr virus-induced G-protein coupled receptor 2 (EBI2) is a protein that in humans is encoded by the GPR183 gene. This gene was identified by the up-regulation of its expression upon Epstein-Barr virus infection of the Burkitt's lymphoma cell line BL41. This gene is predicted to encode a G protein-coupled receptor that is most closely related to the thrombin receptor. Expression of this gene was detected in B-lymphocyte cell lines and lymphoid tissues but not in T-lymphocyte cell lines or peripheral blood T lymphocytes. EBI2 helps B cell homing within a lymph node. EBI2 expression increases during B cell activation, after B cell receptor and CD40 stimulation; its expression decreases during germinal cell development due to BCL6--a transcription factor required in germinal center development. EBI2 must turn off to move B cells to the ...
Pratama A، Ramiscal RR، Silva DG، Das SK، Athanasopoulos V، Fitch J، Botelho NK، Chang PP، Hu X، Hogan JJ، Maña P، Bernal D، Korner H، Yu D، Goodnow CC، Cook MC، Vinuesa CG (April 2013). "Roquin-2 shares functions with its paralog Roquin-1 in the repression of mRNAs controlling T follicular helper cells and systemic inflammation". Immunity. 38 (4): 669-80. PMID 23583642. doi:10.1016/j.immuni.2013.01.011. ...
After the process of affinity maturation in germinal centers, plasma cells have an indeterminate lifespan, ranging from days to months. Recently they have been shown to reside for much longer periods in the bone marrow as long-lived plasma cells (LLPC). They secrete high levels of antibodies, ranging from hundreds to thousands of antibodies per second per cell.[5] Unlike their precursors, they cannot switch antibody classes, cannot act as antigen-presenting cells because they no longer display MHC-II, and do not take up antigen because they no longer display significant quantities of immunoglobulin on the cell surface.[4] However, continued exposure to antigen through those low levels of immunoglobulin is important, as it partly determines the cell's lifespan.[4]. The lifespan, class of antibodies produced, and the location that the plasma cell moves to also depends on ...
The mantle zone (or just mantle) of a lymphatic nodule (or lymphatic follicle) is an outer ring of small lymphocytes surrounding a germinal center.[1] It is also known as the "corona".[2] It contains transient lymphocytes.[3] It is the location of the lymphoma in mantle cell lymphoma. ...
A naive (or inexperienced) B cell is one which belongs to a clone which has never encountered the epitope to which it is specific. In contrast, a memory B cell is one which derives from an activated naive or memory B cell. The activation of a naive or a memory B cell is followed by a manifold proliferation of that particular B cell, most of the progeny of which terminally differentiate into plasma B cells;[note 8] the rest survive as memory B cells. So, when the naive cells belonging to a particular clone encounter their specific antigen to give rise to the plasma cells, and also leave a few memory cells, this is known as the primary immune response. In the course of proliferation of this clone, the B cell receptor genes can undergo frequent (one in every two cell divisions)[8] mutations in the genes coding for paratopes of antibodies. These frequent mutations are termed somatic hypermutation. Each such mutation alters the ...
B1 cells are a sub-class of B cell lymphocytes that are involved in the humoral immune response. They are not part of the adaptive immune system, as they have no memory, but otherwise, B1 cells perform many of the same roles as other B cells: making antibodies against antigens and acting as antigen presenting cells. Notably, most B1 cells do not develop into memory B cells. B1b cells have been shown to be capable of memory responses. See "B1b lymphocytes confer T cell-independent long-lasting immunity." B1 cells are first produced in the fetus and most B1 cells undergo self-renewal in the periphery, unlike conventional B cells (B2 cells) that are produced after birth and replaced in the bone marrow. In January 2011, human B1 cells were found to have marker ...
B-cell growth factor 1, 12kDa, also known as BCGF1, is a human gene. B-cell growth factor is released by T lymphocytes after either lectin or antigen stimulation. It supports the clonal proliferation of B lymphocytes. "Entrez Gene: BCGF1 B-cell growth factor 1, 12kDa". Kumar A, Vasquez A, Maizel AL, Sharma S (1991). "Human BCGF-12kD functions as an autocrine growth factor in transformed B cells". European Cytokine Network. 1 (2): 109-13. PMID 1966378. Vazquez A, Mills S, Sharma S, Maizel AL (October 1988). "Expression of CD23 antigen is not necessary for human 12-kDa B cell growth factor-mediated B cell proliferation". European Journal of Immunology. 18 (10): 1647-9. doi:10.1002/eji.1830181029. PMID 2973416. Mehta SR, Sandler RS, Ford RJ, Sharma S, Maizel AL (1986). "Cellular interaction between B and T lymphocytes: enhanced release of B cell growth factor". Lymphokine Research. 5 (1): 49-57. PMID 3484798. Ennist DL, Greenblatt D, Coffman R, Sharma S, Maizel A, Howard M (November 1987). ...
apoptotic cell. ANA. anti-nuclear Ab. B6. C57BL/6. DC. dendritic cell. GC. germinal center. IC. immune complex. MFI. mean ... are also likely to be different from the classical GC reaction (12). In the autoreactive GC, Ags are also always present and ... Plasticity and heterogeneity in the generation of memory B cells and long-lived plasma cells: the influence of germinal center ... Dynamics of B cells in germinal centres. Nat. Rev. Immunol. 15: 137-148. ...
... of lymphoid follicles and have an integral role in regulation of the germinal center reaction and present antigens to B cells. ... Cyclophosphamide slows or stops cell growth cells. It targets cells that are rapidly dividing which include cancer cells that ... Kosco, Marie H.; Gray, David (1992). "Signals Involved in Germinal Center Reactions". Immunological Reviews. 126: 63-76. doi: ... Follicular dendritic cells are localized in germinal centers ... a leukocyte common antigen, and CD15, a monocyte common antigen ...
This suggests that the number of antigens that activate B cells in different locations is restricted. The most striking result ... adding further information on synovial B-cell maturation and recirculation in RA. This analysis demonstrated somatically ... In the present study 55 IgVH genes amplified from three different anatomical regions of a rheumatoid arthritis (RA) patient ... was the finding of clonally related sequences in different anatomical regions, indicating a recirculation of activated B cells ...
Sarcoma of FOLLICULAR DENDRITIC CELLS most often found in the lymph nodes. This rare neoplasm occurs predominately in adults. ... cells of the lymphoid system and play an integral role in regulation of the germinal center reaction and present antigens to B- ... AntigensIBA 10/01/2013 - "We describe a patient with PNP associated with follicular dendritic cell sarcoma (FDCS), a rare ... 01/01/2010 - "We present here a case of a 69-year-old male diagnosed to have follicular dendritic cell sarcoma of the neck ...
This antigen is found on B cell lines, is strongly expressed by interdigitating cells (IDC), basal epithelial cells, and is ... also present on macrophages, some endothelial cells, and follicular dendritic cells. ... The CD40 antigen is a 44-48 kDa type I integral membrane protein of the tumor necrosis factor receptor (TNFR) superfamily. ... CD40 is implicated in the process of B cell selection in the germinal centre. Studies demonstrated that CD40 monoclonal ...
For T- and B-cell interaction, variations in sCD40 levels may influence germinal center reactions, somatic cell hypermutation, ... Through subtle reductions in CD40 protein levels present on B cells, dendritic cells, and possibly other APCs, the TNFRSF5 −1C, ... CD40-activated dendritic cells are the most potent stimulators of antigen-specific CD4+ and CD8+ T-cell responses and antitumor ... T SNP may deregulate normal germinal center B- and T-cell or dendritic cell and T-cell interactions that can impede the immune ...
B cells are also very efficient antigen-presenting cells, and can contribute to T cell activation through expression of ... B cells both respond to and produce the chemokines and cytokines that promote leukocyte infiltration into the joints, formation ... The success of B cell depletion therapy in rheumatoid arthritis may depend on disruption of all these diverse functions. ... T cells and CD8+T cells. In general, these histologic features are similar to the germinal center (GC) reactions that arise in ...
... centers which others have perceived to provide a ready niche for the entry of naïve B cells that encountered novel antigen. ... In the present study both metabolic and immune deviations observed in the NOD mouse was analyzed. Serum metabolome analysis of ... Increased expression of TACI on NOD B cells results in germinal centre reaction anomalies, enhanced plasma cell differentiation ... In addition, TACI+ cells were observed in NOD germinal centers facilitating increased BAFF uptake and subsequent escape of low ...
PubMed journal article Epstein-Barr virus nuclear antigen 2 inhibits AID expression during EBV-driven B-cell growt were found ... B cells expanding in germinal centers of infectious mononucleosis patients do not participate in the germinal center reaction. ... In the present study, we show that activation of the EBV growth program has a clear inhibitory effect on AID expression, due to ... A cooperative relationship of EBV and the germinal center reaction during the establishment of viral persistence has been ...
Aims/hypothesis We sought to determine whether the presence of natural autoreactive antibodies of B1a cell origin would play a ... and thus are unlikely to originate in germinal centre reactions. Consistently, young NOD mice have a pronounced repertoire of ... In fact, NOD B cell receptor specificity and the capacity of B cells to present antigens to T cells are determinant factors in ... We analysed the peritoneal B1a and B1b + B2 cells and the splenic follicular B cells, marginal zone B cells and B1a cells (Fig ...
... cells of the immune system that are necessary for antigen presentation and the regulation of reactions in the germinal centers ... Follicular dendritic cell sarcoma is an unusual cancer, particularly in the intra-abdominal region. In the present report we ... Retroperitoneal follicular dendritic cell sarcoma has only been rarely reported in the literature to date. A 46-year-old ... Retroperitoneal follicular dendritic cell sarcoma may demonstrate aggressive potential. This study indicated that postoperative ...
... which is required for survival of developing B cells during germinal center reactions in the gut. Both the quality and quantity ... AND B CELLS!). These molecules present small fragments of protein antigens (peptides) to T cells thereby controlling T cell ... favoring the survival of some clones over others) during germinal center (GC) reactions in lymphoid follicles. With a focus on ... B-cell-intrinsic MHCII signaling can be thought of as a critical factor mediating competition among B cell clones for T cell ...
Saud A Sadiq Tisch Multiple Sclerosis Research Center of New York, New York, NY, USA Abstract: Multiple sclerosis (MS) is an ... suggesting an antigen-driven germinal center-like reaction of IgM-producing B cells in MS.69 While neither IgG nor IgM OCBs are ... IgG and IgM antibodies present as OCBs in the CSF are hypothesized to represent an antigen-driven pathophysiology in MS, ... Exosome-mediated transfer of mRNAs and microRNAs is a novel mechanism of genetic exchange between cells. Nat Cell Biol. 2007;9( ...
... indicating that they have been generated through a germinal centre reaction to become memory cells. Similar to B1 B cells, MZ B ... marginal zone B-cells will fail to develop while B-1 cells will still be present. MZ B-cells are the only B-cells dependent on ... The MZ B cells are especially well positioned as a first line of defense against systemic blood-borne antigens that enter the ... B cells and B1 B cells. In humans the splenic marginal zone B cells have evidence of somatic hypermutation in their ...
In situ studies of the germinal center reaction. Adv. Immunol. 60: 267. ... Memory B cells from human tonsils colonize mucosal epithelium and directly present antigen to T cells by rapid up-regulation of ... germinal center is associated with an interesting subset of cells with a phenotype intermediate between germinal center B cells ... detects expression of the MUM1/IRF4 protein in a subset of germinal center B cells, plasma cells, and activated T cells. Blood ...
The latter have been reported to play a crucial role in the control of T and B cell crosstalk and germinal center reactions. ... The latter have been reported to play a crucial role in the control of T and B cell crosstalk and germinal center reactions. ... germinal center Tfh (GC Tfh) and the regulatory counterpart of Tfh cells, the so-called follicular regulatory T (Tfr) cells. ... germinal center Tfh (GC Tfh) and the regulatory counterpart of Tfh cells, the so-called follicular regulatory T (Tfr) cells. ...
In murine germinal center B cells, AID triggers NKG2D ligand expression through chk-1 phosphorylation (50). The persistent chk- ... 2005) Efficient cross-priming of tumor antigen-specific T cells by dendritic cells sensitized with diverse anti-MICA opsonized ... Surprisingly, the anti-MICA antibodies present in MGUS sera fail to inhibit NKG2D-dependent NK cell lysis of K562 targets (SI ... of plasma cell malignancies reflects not only cell-intrinsic alterations but also the impact of host antitumor reactions. ...
... on germinal center cells it protects against apoptosis, but on leaving the germinal center, memory cells lack the antigen; on ... CD40 is present on all B cells and CD40 ligand (or CD154) is present on activated T cells. A well known culture system for B ... it catalyzes chemical reactions. It is involved in signaling through the B-cell receptor (BCR) and such signaling causes cell ... In these centers stimulation by CD31 on endothelial cells and CD154 on T-cells activates the CLL cells, upregulating CD38 and ...
... on germinal center cells it protects against apoptosis, but on leaving the germinal center, memory cells lack the antigen; on ... It is present on CLL cells, but not usually on other types of B cell lymphoma cells. It is also present in the serum of CLL ... it catalyzes chemical reactions.. It is found on many types of cells, but we are really interested in its role on B-lymphocytes ... liver cells, blood cells, brain cells, skin cells, bowel cells and bladder cells. Within a given tissue there are stem cells ...
In contrast, when the target antigen is located only in a tissue or organ remote from the germinal center, B cells capable of ... When the invading antigen is abundant and generally present throughout the body, rogue autoantibody-generating B cells are ... The team says theyll continue to use their new mouse model to study the various molecular reactions involved in the ... germinal centers. [See video.]. • Most of the time, germinal centers serve us well, helping us fight disease and build up a ...
... mice show a low affinity B-cell response, due to a less stringent selection of clones that enter the germinal center.10 ... cells present in peripheral blood of Noxa−/−/TCL1 and TCL1 mice. The percentage of CD5+CD19+ cells was determined by flow ... revealing a role for NOXA in refining the response of B cells and T cells to antigens.9,10 Noxa−/− ... NOXA mRNA levels in TCL1 CLL cells were determined by quantitative polymerase chain reaction, which showed a significantly ...
T helper cells requires the B7 molecule present on the antigen presenting cell to bind with CD28 molecule present on the T cell ... germinal centers of lymph nodes and clonal selection of B cells, see Lymph node, Germinal center, and Clonal selection. ... Increased chances of autoimmune reactions[edit]. For more details on autoimmunity, see Autoimmunity. ... Activation of the T helper cells by antigen-presenting cells.. *Costimulation of the B cell by activated T cell resulting in ...
In the germinal centers, B cells with a low affinity for the antigen undergo apoptosis (20). Tingible body macrophages are ... The TUNEL-stained material, that is, the nuclei of apoptotic cells, was not localized with CD68, but seemed to be present ... and ES clones carrying the mutation were identified by polymerase chain reaction (PCR). Mice derived from two ES clones had ... few TUNEL-stained cells (0.6 cells per macrophage) were associated with macrophages expressing CD68 in the germinal center (Fig ...
B cells present a piece of the invader, an antigen, to T cells. The antigen converts a naïve T cell to a helper T cell that ... which suppresses the reaction of structures called germinal centers. This is where immune system T cells and B cells interact ... "Germinal centers have mostly B cells with a few helper T cells to regulate them. The B cells mutate to make high-affinity ... cell that launches antibody production in the germinal centers.. With Tfr turning germinal centers off and Tfh turning them on ...
  • Marginal zone B cells are noncirculating mature B cells that segregate anatomically into the marginal zone (MZ) of the spleen. (
  • The MZ B cells are especially well positioned as a first line of defense against systemic blood-borne antigens that enter the circulation and become trapped in the spleen. (
  • Since the last few years, many studies have characterized Tfh cells from lymph nodes and spleen of HIV-infected individuals and SIV-infected macaques. (
  • Significantly, Blimp-1 was also found in a fraction (4-15%) of germinal center B cells in murine spleen and human tonsils. (
  • Upon secondary exposure to TD Ags, circulating or marginal zone memory cells proliferate both in T cell-rich regions and in GCs of spleen and lymph nodes. (
  • A) Comparison of mRNA levels in CD19 + CD5 + cells in the peripheral blood and spleen of TCL1 mice (n=3). (
  • Germinal centers are found in the lymph nodes and the spleen. (
  • Immature B cells then express IgM at their surface and exit the bone marrow to enter the circulation and move to peripheral lymphoid organs such as the spleen or the lymph nodes. (
  • This anatomic compartment is more prominent in lymphoid organs that are continuously exposed to not only a high flow of external antigens, particularly the spleen, but also the mucosa-associated lymphoid tissue (MALT) and the mesenteric lymph nodes. (
  • Spread of infection to the spleen generates an antigen-nonspecific, T-cell-dependent B-cell activation ( 32 , 38 ) and an infectious mononucleosis-like disease similar to that observed in adolescent EBV infection ( 13 , 43 ). (
  • The pivotal role that B cells play in latency is confirmed by the inability after intranasal inoculation to establish splenic latency in mice deficient in B cells (μMT) ( 46 , 55 ) and their requirement for spreading of infection from the lung to the spleen ( 41 ). (
  • This profile helps in distinguishing SMZL from other small B-cell lymphomas secondarily involving the spleen. (
  • The variant A strain can destroy the germinal centers of the lymph nodes, where antigen presentation takes place, as well as infect lung, spleen, liver and kidney tissues. (
  • It should be noted that for each immunogen many germinal centers will be generated in the spleen or lymph nodes (or other secondary lymphoid tissue) which will increase the diversity of antigen specific B cell clones. (
  • In the spleen, T. brucei induces extramedullary B lymphopoiesis as evidenced by significant increases in HSC-LMPP, CLP, pre-pro-B, pro-B and pre-B cell populations. (
  • The frequencies and absolute numbers of T-cell, B-cell, and macrophage populations in spleen and peripheral blood from P. chabaudi -infected BALB/c mice were compared and found to be significantly altered during acute infection. (
  • The kinetics of the redistribution of the different cell types in spleen and peripheral blood were different, with T and B cells appearing in the blood when their frequencies and absolute numbers in the spleen were low. (
  • The sequential appearance, regulation and development of the different cell populations in the spleen during malaria infections are still poorly understood. (
  • During responses to infectious pathogens such as certain viral infections, e.g., lymphocytic choriomeningitis virus infection in mice, the immune response is often associated with high levels of apoptosis in the spleen, both in the selection of antigen-specific cells in the early stages of infection, as well as the silencing of the immune response at the end of the infection (reviewed in reference 36 ). (
  • In parasitic infections, apoptosis has been shown to be induced in fresh splenocytes and in in vitro-cultured spleen cells from mice infected with Schistosoma mansoni ( 9 , 11 ), Trypanosoma cruzi ( 21 ), and Toxoplasma gondii ( 16 ), where it has been implicated as a mechanism whereby parasites escape the immune response. (
  • B-cells originate in the bone marrow, MALT, spleen. (
  • 2 , 3 We have also found that the NOXA/MCL-1 balance in CLL cells is inverted in the lymph node compared to peripheral blood, which is indicative of an increase in chemoresistance. (
  • Lymphadenopathy and lymph node B cell activation are independent of MyD88-signaling.Control C57BL/6 (wildtype) and congenic MyD88−/− mice (n = 6 per group) were infected with host-adapted B. burgdorferi for 10 days. (
  • Therefore, we determined the role of the adaptor protein MyD88, important in TLR and IL-1-mediated innate signaling, in regulation of initial B cell activation and/or the lymph node enlargement. (
  • solid mass -extramedullary myeloid tumor (granulocytic sarcoma): malignancy of hematopoietic cells, from myeloid cells or precursors (granulocytes, monocytes) presents as solid mass -many prefer one type of manifestation, these types of disease manifestations are not exclusive-often overlap -overlap of CLL and SLL: same biologic disease, but differs if blood and marrow (CLL) vs. enlarged lymph node due to growth (SLL). (
  • high grade: lymphoma=present as rapidly enlarging mass. -low grade: mildly enlarged neck lymph node (example) present for years or as mild degree of lymphadenopathy on imaging study. (
  • Antigens enter the subcapsular sinus (SCS) via afferent lymphatics and escape the lymph node via efferent lymphatics. (
  • We have found the variant A strain to be the predominant form present in the lymph node biopsies of HIV infected patients. (
  • It is essential for proper development of lymph node germinal centers and Peyer's patches, and for combating intracellular pathogens such as Listeria (1‑3). (
  • Our results support the hypothesis that increased TACI expression on NOD B cells contributes to the pathogenesis of type 1 diabetes in the NOD mouse. (
  • Deregulation of AID may lead to the aberrant activation or persistence of both genetic processes, thus contributing to the pathogenesis of B-cell lymphomas by mistargeted mutagenesis or recombination. (
  • We will explore some hypothesis to explain the increased proportion of Tfh cells reported in chronically infected individuals and the impact on HIV pathogenesis. (
  • The pathogenesis of plasma cell malignancies reflects not only cell-intrinsic alterations but also the impact of host antitumor reactions. (
  • In order to elucidate the molecular mechanisms governing the establishment of latent infection in B cells by gamma-2-herpesviruses, we have used a gammaherpesvirus, designated murine herpesvirus 68 (MHV-68), since its pathogenesis can be readily investigated in the laboratory mouse ( 12 , 33a , 36 ). (
  • Thus, the identification of viral genes expressed during the establishment of infection in GC B cells is central for an understanding of MHV-68 pathogenesis. (
  • Currently, the nature and source of citrullinated antigens driving the humoral autoimmune response within synovial ectopic lymphoid structures (ELS) is a crucial unknown aspect of RA pathogenesis. (
  • Nevertheless, recognition of autoreactive plasma cells in the swollen salivary glands [2,and existence of IgA autoantibodies in sera and saliva of SS sufferers [4-raise queries about the foundation and contribution of salivary gland plasma cells towards the pathogenesis of SS. (
  • It is well established that these B-cell-intrinsic molecular changes are not sufficient to fully induce transformation ( 5 ) and that secondary genetic mutations and other factors have important roles in the pathogenesis of B-cell malignancies. (
  • Autoimmune diseases are characterized by pathogenic immune responses to self-antigens. (
  • In systemic lupus erythematosus (SLE), many self-antigens are found in apoptotic cells (ACs), and defects in removal of ACs from the body are linked to a risk for developing SLE. (
  • In this study, we investigated how memory to AC-derived self-antigens develops and the contribution of self-memory to the development of lupus-related pathology. (
  • Thus, we provide evidence for a selective self-memory that underlies progression of the response to self-antigens with implications for SLE development therapy. (
  • Systemic lupus erythematosus (SLE) is characterized by circulating IgG autoantibodies specific for apoptotic cell (AC)-derived self-antigens ( 1 , 2 ). (
  • Environmental triggers, such as UV light, drugs, and viral infections, are thought to cause cell destruction and expose self-antigens to the immune system, thereby contributing to initiating onset of and exacerbating a flare in an existing SLE condition ( 2 , 6 ). (
  • This suggests that the immune response to self-antigens develops and reaches a threshold before becoming pathogenic. (
  • However, the experimental description of the sequential immunological events behind this are less known, even though it has been shown that the response to self-antigens can be boosted and that long-lived plasma cells (PCs) to self-antigens exist ( 9 , 10 ). (
  • It is believed they are especially reactive to bacterial cell wall components and self-antigens which are the products of aging. (
  • Blimp-1 is expressed in plasma cells derived from either a T-independent or T-dependent response in plasma cells that have undergone isotype switching and those resulting from secondary immunization. (
  • The extrafollicular nature of this B cell response and its strongly IgM-skewed isotype profile bear the hallmarks of a T-independent response. (
  • ELISPOT analysis was conducted to determine numbers of (C) borrelia-specific IgM or (D) all Ig-isotype secreting borrelia-specific cells. (
  • This is the time during which critical signals, sent by the T FH cells, induce isotype switching (so-called class switching, which exchanges IgM for IgG) and expansion of B cell clones starts. (
  • Immature B cells bearing non-productive rearrangements of either chain can be rescued by new rearrangements on the other allele or, in the case of the light chains, by switching to the other isotype. (
  • In B cells, the binding of CD154 to CD40 causes target B cells to undergo isotype switching and growth, thereby aiding CD4-positive cells in the activation of B cells (Janeway et. (
  • In the absence of CD154, B cells are unable to undergo isotype switching, causing immunodeficiencies in the patients with HIGM1 ( OMIM ). (
  • 1 The germinal center reaction plays a pivotal role in the generation of the majority of B-cell lymphomas, such as follicular (FL), and some diffuse large B-cell (DLBCL) 2 , 3 and Hodgkin lymphomas (HL). (
  • 4 Thus, genetic and environmental factors that disrupt normal germinal center reactions may increase the risk of these lymphomas. (
  • However, in B cell lymphomas, overproliferation and mutation of B cells are the problems, Dong said. (
  • Hitting the regulatory T cell off-switch might help against lymphomas and autoimmune diseases, while blocking it could permit an immune response against other cancers. (
  • Since the first recognition of certain large B-cell lymphomas in which the tumor cell content was dramatically outnumbered by reactive T cells or less often histiocytes, this descriptive term and related terms have been used to characterize a variety of lymphoma subtypes, and different studies have varied in the criteria used for this designation. (
  • The original term of "T-cell-rich B-cell lymphoma" was introduced to describe a variety of B-cell lymphomas with a prominent T-cell reaction mimicking T-cell lymphoma.1 The presence of less than 10% (sometime as low as 1%) of usually large, atypical B cells in a background rich in T cells was the unifying feature of the diagnosis. (
  • B-cell lymphomas with a prominent T-cell reaction ranged from low-grade lymphomas such as chronic lymphocytic leukemia1 and follicular lymphoma to diffuse large B-cell lymphomas.1-3 These were important diagnostic contributions that emphasized the utility of immunohistochemistry, and in some cases molecular studies,4 for the correct identification of the neoplastic population in an unusually rich reactive milieu. (
  • As a low-grade tumour, it is the most commonly occurring subtype among indolent B cell lymphomas in the Western world [ 1 , 2 ]. (
  • Extranodal marginal zone (MZ) B-cell lymphomas of the mucosa-associated lymphoid tissue (MALT) arise from lymphoid populations that are induced by chronic inflammation in extranodal sites. (
  • MALT lymphoma is the commonest MZL type, accounting for 5% to 8% of all B-cell lymphomas, 30 , 31 and has been described in virtually all tissues, often in organs that are normally devoid of germinal centers. (
  • The results may also help us understand the mechanism behind the development of SLE-like autoimmune diseases and B cell lymphomas. (
  • Besides having implications for immune regulation, the results may explain how persistent activation of self-reactive B cells induces the development of autoimmune diseases and B cell lymphomas. (
  • Our results not only provide fundamentally insights for successful immunotherapy and long-term protection against B lymphomas, but also present a simple, therapeutic vaccine that can be translated easily due to the facile and inexpensive method of preparation. (
  • In contrast to other B-cell lymphomas, no consistent or unique genetic lesion has been associated with SMZL. (
  • Most cases also display scattered large, EBV-positive B-cells that may give rise to secondary B-cell lymphomas in a subset of patients. (
  • Subclones of these cells may acquire independent genetic changes to produce non-Hodgkin lymphomas and Hodgkin lymphoma. (
  • Although malignant B cells maintain the features of their normal counterparts in most instances, to date, such replacements have not been described for human B cell lymphomas. (
  • VH replacements were seen in two extranodal marginal zone B cell lymphomas. (
  • Mice heterozygous for a transgene Col13a1 del expressing a mutant collagen XIII developed clonal mature B-cell lineage lymphomas originating in mesenteric lymph nodes (MLN). (
  • The lymphomas did not express the mutant collagen XIII, indicating that its influence on tumorigenesis was B-cell extrinsic and likely to be associated with collagen XIII-positive tissues drained by the MLN. (
  • The studies to be presented here were prompted by the unanticipated findings that mice heterozygous for the Col13a1 del allele developed T-cell-rich, histiocyte-rich B-cell lymphomas appearing in mesenteric lymph nodes (MLN) and that the incidence of lymphomas was significantly reduced in mice raised under specific pathogen-free (SPF) conditions. (
  • Microscopic examination revealed that the tumor was composed of fat to long spindle cells with multinodular infiltration that were arranged in a storiform pattern (Figure 2 ). (
  • The tumor exhibited necrosis, cell atypia and obvious mitosis. (
  • Mandatory criteria include confirmed mature B-cell nature of the tumor, CD20 expression, and if needing additional markers (bcl-2, bcl-6, MUM- 1), B-cell clonality and other criteria are used. (
  • At the beginning of the 21st century the investigators paid attention to the fact that this hemopoietic tissue tumor was in many respects regulated by cells of so called non-tumor environment, i.e. (
  • Infiltration of tumor tissue by immune cells was reflected by gene expression profiles in the tumor tissue. (
  • Two types of immune response were defined accordingly that were associated with microenvironment cells infiltrating the tumor. (
  • Regional lymph nodes (RLNs) draining malignant human tumors, one of the first components of the human immune system to have contact with tumor cells or their products, are considered the first barrier against tumor progression 1 . (
  • The most decisive evidence of the existence of an immune response to tumors in humans, are the histological changes in RLNs, consisting of an prominent sinus histiocytosis and hyperplastic germinal follicular centres, even in absence of metastatic tumor cells. (
  • These reactions would represent a host response against tumor cells in which all the immune cells are involved 2 . (
  • suggested that cytokines such as interleukin-4 could play a role in the histogenesis of this lymphoma.5 The same group later characterized the T-cell infiltrate as being predominantly composed of non-activated CD8/TIA-1/granzyme B T cells, and speculated that it might have been less effective in mediating a host anti-tumor response.6 Delabie et al. (
  • CD4 T cells specific for each of the viruses produced all seven possible combinations of the cytokines gamma interferon (IFN-γ), interleukin-2, and tumor necrosis factor alpha. (
  • Characteristics that are important for T-cell function in the control of viral infections include the production of cytokines, such as gamma interferon (IFN-γ), interleukin-2 (IL-2), and tumor necrosis factor alpha (TNF-α) ( 12 , 23 , 32 ), and proliferative capacity. (
  • In a delayed-treatment, aggressive, murine model of A20 B lymphoma that mimics human diffuse large B cell lymphoma, we show that therapeutic A20 lysate vaccine adjuvanted with an NKT cell agonist, α-galactosylceramide (α-GalCer), provides long-term immune protection against lethal tumor challenges and the antitumor immunity is primarily CD8 T cell dependent. (
  • In the following carcinomas, a minority of cases is positive: prostate adenocarcinoma, adrenal cortical carcinoma, pancreas adenocarcinoma, gastric adenocarcinoma, serous carcinoma, medullary and papillary thyroid carcinoma, carcinoid tumor, neuroendocrine carcinoma and Merkel cell carcinoma. (
  • Histologically, the tumor has diagnosed as a pituitary adenoma with GH positive cells. (
  • Invasive pituitary adenomas have been defined when invasion of tumor cells to adjacent tissues like dura, bone, sinus mucosa or cavernous sinus and rarely brain paranchyma could be shown ( 1 , 7 - 9 ). (
  • CD154 is a member of the tumor necrosis factor family and is present as a costimulatory molecule on T cells. (
  • In this case, the activated APC can continue on to prime cytotoxic T cells for the purpose of tumor elimination ( d ). (
  • A) A tumor comprised of small dark cells coursing throughout the dermis in large nests is present. (
  • It is present on CLL cells, but not usually on other types of B cell lymphoma cells. (
  • The B-Cell Lymphoma Moon Shot is revolutionizing the conventional medical research approach to rapidly translate findings into patient treatment options and develop personalized therapeutic strategies. (
  • T-cell/histiocyte-rich large B-cell lymphoma (THRLB-CL) can be used as a paradigm to highlight the difficulties in defining specific subtypes of diffuse large B-cell lymphoma. (
  • Finally, both NLPHL and THRLBCL may progress to more typical diffuse large B-cell lymphoma, once the neoplastic cells sheet out and the stroma is no longer the predominant component. (
  • However, at this stage the emphasis was on the distinction from peripheral T-cell lymphoma, and not on the delineation of a new disease entity. (
  • identified a distinct subgroup predominantly rich in non-epithelioid histiocytes rather than T cells with distinctive clinicopathological features (the so-called "histiocyte-rich B-cell lymphoma").7 Their study also stressed the similarities and possible relatedness with NLPHL, which is likewise characterized by relatively rare neoplastic cells in an abundant non-neoplastic cellular environment. (
  • Histogenetically, follicular lymphoma arises from germinal centre B cells. (
  • In this study, our goal was to develop a simple, clinically relevant, and easily translatable therapeutic vaccine that provides durable immune protection against aggressive B cell lymphoma and identify critical immune biomarkers that are predictive of long-term survival. (
  • Using experimental and computational methods, we demonstrate that the initial strength of germinal center reaction and the magnitude of class-switching into a Th1 type humoral response are the best predictors for the long-term immunity of B lymphoma lysate vaccine. (
  • Clinically, grade 3B follicular lymphoma is treated like diffuse large B-cell lymphoma . (
  • Figure 52.18 Angioimmunoblastic T-cell Lymphoma. (
  • In diffuse large B-cell lymphoma CD138 positivity is associated with a poorer prognosis (as it indicates activated B-cell phenotype - together with positivity for MUM1). (
  • Recently, some publications have reported CD138 reactivity in cases of B-cell acute lymphoblastic leukemia/lymphoma. (
  • Adaptive immunity in general, and the germinal center in particular, play a role in the initiation of lymphoma and and autoimmune disorders such as rheumatoid arthritis. (
  • It has been suggested that nongenetic B-cell-extrinsic contributions to lymphoma induction, progression, and survival may be multiple. (
  • AILD is a type of peripheral T-cell lymphoma that is clinically characterized by high fever and generalized lymphadenopathy. (
  • AILD-type dysplasia with an oligoclonal T-cell pattern has frequently been shown to progress into AILD-type lymphoma. (
  • The disease can easily be missed by unsuspecting hematologists, as patients may present with clinical problems that mimic disorders such as multicentric Castleman disease, lymphoma, plasma cell neoplasms and hypereosinophilic syndromes. (
  • Involvement of blood-forming and lymphoid organs, manifesting as lymphadenopathy, eosinophilia, and polyclonal hypergammaglobulinemia, is common and IgG4-RD often mimics other hematologic conditions such as multicentric Castleman disease, lymphoma, plasma cell neoplasms, and hypereosinophilic syndromes (HES). (
  • These cells reside in resting or 'immature» state in non lymphoid tissues, where they efficiently capture and process antigens. (
  • In situ hybridization of EBV-encoded RNA sequences in lymph nodes usually demonstrates five- to ten-fold more EBV-positive cells in lymphoid tissues of HIV-infected patients compared with the lymphoid tissue in normal patients. (
  • Alternatively a recent research of full-length proteins and many deletion mutants indicated in insect cells demonstrated that COL1 and NC1 aren't necessary for trimerization of collagen IX even though the COL1-NC1 region may be important for string specificity (16). (
  • A cooperative relationship of EBV and the germinal center reaction during the establishment of viral persistence has been postulated, but the contribution of EBV latent genes to the respective genetic events remains to be investigated in detail. (
  • MGUS plasma cells display chromosomal alterations, including translocations that fuse sequences from the IgH locus to partner genes with oncogenic potential, whereas the progression to MM involves additional mutations in growth and survival pathways ( 5 - 7 ). (
  • In the Nature Medicine paper, Dong and colleagues found that a subgroup of regulatory T cells that expresses two genes, Bcl-6 and CXCR5, moves into germinal centers in both mice and humans, where they have access to B cells. (
  • Bcl-6 produces a protein called a transcription factor, which moves into the cell nucleus to regulate other genes. (
  • Its further diversification involves the antigen-driven introduction of point mutations into the V regions of Ig genes ( 1 ). (
  • Significant evidence for positive selection by classical T-dependent antigen was found in only 5/27 IGHV and 6/15 IGKV+IGLV mutated genes. (
  • The unique combination of heavy and light chain genes defines the immunological activity of a B cell and also its identity, also referred to as its clonotype. (
  • While the achievable depth of these amplicon-based approaches provided remarkable resolution (10 5 -10 6 chains in a single experiment) [ 8 ], a significant limitation of this technology for functional studies of the immune system is that it only sequences a single chain and cannot provide information on endogenous pairing of IgH/IgL genes to definitively identify a B cell clonotype. (
  • Genomic DNA was amplified by seminested polymerase chain reaction(PCR), and the cDNA corresponding to the RNA was amplified by PCR using primersspecific for each IgVH family. (
  • In the remaining common 3′-VH regions, these mutations could be used to establish a phylogenetic relation between the sequences, rendering the possibility of artefactual chimaeric polymerase chain reaction products very unlikely. (
  • B cells both respond to and produce the chemokines and cytokines that promote leukocyte infiltration into the joints, formation of ectopic lymphoid structures, angiogenesis, and synovial hyperplasia. (
  • In addition, activated B cells can synthesize cytokines and membrane-associated molecules that provide nonspecific help to adjacent T cells. (
  • These actions bring about the production of cytokines and activation of inflammatory cells, leading to production of MMPs and neutrophilic elastase. (
  • Cells producing three or two cytokines (triple producers and double producers) represented nearly 50% of the total response to each of the viruses. (
  • Triple producers expressed the highest levels of cytokines per cell, and single producers expressed the lowest. (
  • There are very limited data available on the cytokine coexpression profiles of virus-specific CD4 T cells ( 6 , 8 , 9 , 11 , 13 , 14 ), and a comprehensive analysis of the relationship between the ability of virus-specific CD4 T cells to coexpress multiple cytokines and other functions has not been performed. (
  • Our results demonstrate that triple producers are functionally superior to single producers not only in the numbers but also in the amounts of cytokines produced per cell and in costimulatory and degranulation potential. (
  • T-F--innate-derived signals and cytokines collaborate with BCR signals to activate B cells? (
  • DC- and B cell-derived IL-6 and IL-27 cytokines maintain and reinforce this lineage, leading to upregulation of the T FH transcription factors BCL6, c-Maf, and CXCR5. (
  • A variety of adjuvants, systemic cytokines, antigen formulations, doses, routes of delivery and frequency of vaccinations have been studied. (
  • Alternative endpoints that permit the rapid assessment of the biologic effects of adjuvants, cytokines, antigen formulation, frequencies and dose in human subjects are needed. (
  • Fig1.1: Release of cytokines due to T-cell activation causing an inflamed synovium and pannus. (
  • 4 Laboratory for Innate Cellular Immunity, RIKEN Research Center for Allergy and Immunology, Yokohama, Kanagawa 230-0045, Japan. (
  • Regulatory T cells prevent unwanted or exaggerated immune system responses, but the mechanism by which they accomplish this has been unclear," said paper senior author Chen Dong, Ph.D., professor in MD Anderson's Department of Immunology and director of the Center for Inflammation and Cancer. (
  • 3 Institute for Cancer Genetics, 4 Department of Pathology and Cell Biology, 5 Department of Genetics and Development, and 6 Department of Microbiology and Immunology, Columbia University, New York, New York, USA. (
  • Moreover, flow cytometry analyses revealed that germinal centre B cells in NOD failed to down-regulate TACI. (
  • Serum IgM autoreactivity profiles were determined by ELISA and the secretory properties and activation status of B1a cells were characterised by enzyme-linked immunosorbent spot (ELISPOT) assay and flow cytometry. (
  • The effect of NOD IgM produced by B1a cells on NOD.severe combined immunodeficient (SCID) beta cells was examined in co-cultures: IgM binding was measured by flow cytometry and real-time PCR was used to study oxidative stress responses. (
  • With the availability of multicolor flow cytometry, it is now possible to simultaneously measure multiple functions of virus-specific CD4 T cells ( 19 ). (
  • The team says they'll continue to use their new mouse model to study the various molecular reactions involved in the progression of an autoimmune response. (
  • These data demonstrate that MFG-E8 has a critical role in removing apoptotic B cells in the germinal centers and that its failure can lead to autoimmune diseases. (
  • Apoptotic cells are rapidly engulfed by phagocytes, a process that should prevent inflammation and the autoimmune response against intracellular antigens that can be released from the dying cells ( 2 - 4 ). (
  • It is anticipated that a greater understanding of development pathways will facilitate effective vaccine design for challenging targets such as HIV [ 3 ], as well as supporting research into autoimmune disease [ 4 ] and immune reactions to therapeutic agents. (
  • Here it is proposed that this CD8+ T-cell deficiency underlies the development of chronic autoimmune diseases by impairing CD8+ T-cell control of Epstein-Barr virus (EBV) infection, with the result that EBV-infected autoreactive B cells accumulate in the target organ where they produce pathogenic autoantibodies and provide costimulatory survival signals to autoreactive T cells which would otherwise die in the target organ by activation-induced apoptosis. (
  • It is also proposed that deprivation of sunlight and vitamin D at higher latitudes facilitates the development of autoimmune diseases by aggravating the CD8+ T-cell deficiency and thereby further impairing control of EBV. (
  • however, in 2003 the EBV-infected autoreactive B-cell hypothesis of autoimmunity was proposed as the basis for human chronic autoimmune diseases [ 5 ]. (
  • The present article presents a further development of this hypothesis, proposing that susceptibility to develop chronic autoimmune diseases after EBV infection is dependent on a genetically determined quantitative deficiency of the cytotoxic CD8+ T cells that normally keep EBV infection under tight control. (
  • B-cells participate in the autoimmune response that precedes the onset of type 1 diabetes, but how these cells contribute to disease progression is unclear. (
  • Thus, NETs could represent a source of citrullinated antigens fuelling the ACPA autoimmune response within the RA synovium. (
  • Systemic autoimmune diseases: The symptoms and damage occurs throughout the body, i.e the antigen is not tissue-specific. (
  • Localized autoimmune diseases: The damage is localized, i.e ., the antigen is tissue specific. (
  • Launch Sj?gren's symptoms (SS) is a heterogeneous autoimmune disease seen as a focal mononuclear cell infiltration in the exocrine glands and great serum titres of Ro/SSA, La/SSB and rheumatoid aspect (RF) autoantibodies. (
  • Alongside the reality that both Ro and Fadrozole La antigens have already been discovered in the salivary glands of SS sufferers [16,there is a likelihood that autoimmune plasma cells are created at the website of irritation. (
  • As an end result, anti-CD20-treated autoimmune patients showed drastic reductions in B-cell figures, but unchanged serum levels of autoantibodies [25, (
  • IgM of NOD B1a cell origin was able to bind to pancreatic beta cells in vitro and induce expression of inducible nitric oxide synthase ( Nos2 ). (
  • Damage-associated molecular patterns (DAMPs) released from dying cells after cigarette smoking increase the number of apoptotic cells, suppress efferocytosis, induce hypoxia and oxidative stress, and prolong the inflammatory changes, even after smoking cessation. (
  • Thus, there is evidence for the value of melanoma vaccines incorporating defined antigen and a need to improve their ability to induce T cell responses. (
  • Thus, at the stage of cytotoxic beta cell destruction, B cells would be highly exposed to beta cell-related autoantigens (AAgs), leading to preferential activation of B cells with autoreactive potential. (
  • Virus-specific CD4 T cells are endowed with multiple functions, such as cytokine production, CD40 ligand (CD40L) expression (associated with the costimulation of CD8 and B cells), and degranulation (associated with cytotoxic potential). (
  • Here, we evaluated the cytokine coexpression profiles of CD4 T cells specific for antigens of different viruses causing human infections and then further evaluated the levels of cytokine expression, CD40L expression (costimulatory potential), and degranulation (cytotoxic potential). (
  • B-cells may also have a tolerogenic function, as the transfer of activated B-cells prevents type 1 diabetes, probably by triggering the apoptosis of β-cell-reactive cytotoxic T-cells (CTLs) and/or inhibiting APC activity in NOD mice ( 11 ). (
  • There is evidence of T-lymphocytic mediated cytotoxic reaction, involving thyroid antigen. (
  • This hypothesis proposes that, in genetically susceptible individuals, EBV-infected autoreactive B cells seed the target organ where they produce pathogenic autoantibodies and provide costimulatory survival signals to autoreactive T cells which would otherwise die in the target organ by activation-induced apoptosis [ 5 ] (Figure 1 ). (
  • While host-adapted spirochetes are not expected to express significant amounts of OspA, other proteins or lipids may provide mitogenic signals to B cells in vivo. (
  • 4) In the GC, prolonged interactions between GC T FH and GC B cells confirm the T FH lineage commitment, resulting in mutual exchange of survival signals that result in GC maintenance. (
  • The B-cell maturational process is accompanied by changes in the expression of cell-surface and intracellular proteins and requires signals from the specialized microenvironments. (
  • CONCLUSION: In view of the importance of B cell-T cell interactions in the maintenance of a functional immune system, disruption of B-lymphocyte development could have direct implications on the course of AIDS progression. (
  • The follicles contained mitotically active germinal centers surrounded by well-defined lymphocyte mantles and composed predominantly of CD20 + B cells. (
  • We have recently demonstrated the appearance of interleukin-4 (IL-4)-producing FcɛRI + non-B, non-T cells in the spleens and peripheral blood of P. chabaudi -infected mice during and shortly after peak parasitemia ( 13 ) indicative of an altered lymphocyte trafficking during murine Plasmodium infections as described by others ( 3 , 18 ). (
  • Systemic complexities are damage to various other organs like lungs, myocardia, pericardia pleura, eyes, and Central Nervous System as a result of inflammatory reactions (fig-1.1). (
  • In many centers, systemic therapy is guided by rheumatologists, yet nearly every medical, surgical and pathology specialty must be aware of this entity and its protean manifestations. (
  • The theory is those cells suppress an immune system response in the tumor's microenvironment that otherwise might have attacked the cancer. (
  • When the adaptive immune system detects an invading bacterium or virus, B cells present a piece of the invader, an antigen, to T cells. (
  • Polyclonal B cell response is a natural mode of immune response exhibited by the adaptive immune system of mammals . (
  • The collection of various cells , tissues and organs that specializes in protecting the body against infections is known as the immune system . (
  • One of the hallmarks of the immune system is the ability to recognize large numbers of antigens. (
  • We propose that the many different variable sequences present in IVIg introduce a multitude of new foreign epitopes re-directing the immune system. (
  • Therefore, we suggest that rather than acting as an active anti-inflammatory component, IVIg interferes with establishing an efficient immune response against a specific antigen via a huge diversity of epitopes re-directing the immune system towards a massive immune response against IVIg. (
  • Type 1 diabetes develops following the selective loss of pancreatic β-cells due to a self-destructive mechanism mediated by the patient's own immune system ( 1 ). (
  • However, other immune system cells are also crucial in the disease development. (
  • A major selective force that regulates the phenotype of an infecting microbial pathogen population is the host's immune system, which is also highly adaptive, especially in discriminating self and nonself antigens ( 2 , 4 ). (
  • Chief among these is the accumulating knowledge of how the immune system contributes to all phases of atherogenesis, including well-known inflammatory reactions consequent to intimal trapping and oxidation of LDL. (
  • B cells are an essential component of the adaptive immune system . (
  • Blimp-1 expression in the germinal center is associated with an interesting subset of cells with a phenotype intermediate between germinal center B cells and plasma cells. (
  • Indeed, Noxa − / − mice do show a particular phenotype when exposed to antigens, revealing a role for NOXA in refining the response of B cells and T cells to antigens. (
  • NOXA and MCL-1 are differentially expressed in TCL1 mice, ablation of NOXA does not change the phenotype of TCL1 CLL cells. (
  • The walla phenotype was identified by forward genetic screening of ENU-mutagenized G3 mice: a total of three male siblings exhibited null T-dependent IgG responses to rSFV-encoded antigen ( T-dependent Humoral Response Screen ) but normal T-independent IgM responses and serum IgA levels ( T-independent B Cell Response Screen ) (see figure). (
  • In this study, we analyzed the phenotype and functional characteristics of islet-infiltrating B-cells in the diabetes-prone NOD mouse and in the insulitis-prone but diabetes-resistant (NOD×NOR)F1 mouse. (
  • The results indicate that islet-infiltrating B-cells accumulate in the islets influenced by sex traits, and their phenotype is compatible with a downregulated population. (
  • In contrast to EBV, comparatively little is known about the natural sequence of events during KSHV infection or the phenotype of B cells during long-term latent infection. (
  • myeloid malignancies: arising from mature/immature members of granulocytic, monocytic, erythroid, megakaryociytic, mast cells -lymphoid malignancies: arising from mature/immature members of B, T, NK cells -acute leukemia: majority are classified as AML or ALL. (
  • Furthermore, they indicate that in SMZL, as in other B cell malignancies, a complementarity imprint of antigen selection might be witnessed either by IGHV, IGKV, or IGLV rearranged sequences. (
  • Patients with primary immune disorders are more likely to develop benign T-cell expansions of CD4-/CD8- α/β T cells than T-cell malignancies. (
  • Among haematolymphoid neoplasms, CD138 is expressed in practically all cases of plasma cell malignancies. (
  • Maintenance of optimum level of ROS is definitely important for developing cells and stem cells and in metabolically active tissues where the high-energy demand makes them more vulnerable to oxidative stress. (
  • Autoimmunity is the inability of an organism in recognizing its own parts as self , which triggers an abnormal immune response against its own cells or tissues. (
  • Institute of Clinical and Molecular Biology, GSF-Research Center for Environment and Health, Marchioninistrasse 25, 81377 München, Germany. (
  • Little is known about the molecular mechanisms that determine the development of B cells following exposure to cognate Ag, particularly those involved in the choices between a short-lived plasma cell vs GC development or plasma vs memory fate following the GC reaction. (
  • Importantly, she adds, "It also suggests that if you know enough about the disease and the molecular messaging systems involved, it may be possible in future to modulate the germinal center response. (
  • In addition, we need beyond state-of-the-art computational models that address specific questions related to GCR disturbances in BCL and RA, and multiscale models that integrate models at the cellular level with models at the molecular level to study how disturbed molecular pathways impact on the spatiotemporal dynamics of the GC cells. (
  • The role of water in many atmospheric reactions remains poorly understood at the molecular level because it is difficult to distinguish nonspecific effects, such as collisional activation, from direct participation of water as a catalyst. (
  • Therefore, elucidating the cellular and molecular mechanisms underlying T cell help to B cell is of critical importance for the design of better vaccines. (
  • In the future, we will focus on the molecular mechanisms underlying Bcl-6 induction and regulation by upstream signaling pathways, including cell-cell contact and cell metabolism. (
  • Molecular genetics: Clonal T-cell rearrangements are detectable by PCR or Southern blot studies in at least 75% of cases. (
  • 4 Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria. (
  • One of the key question in systems biology is how biological systems (e.g., cells, molecular networks, germinal center) operate upon interaction with their external environment. (
  • The last 20 years have witnessed remarkable progress in understanding the cellular origins and molecular mechanisms involved in the development of B-cell lineage neoplasms. (
  • The gene expression study of normal B-cell compartments may additionally contribute to our understanding of the molecular abnormalities of the corresponding lymphoid tumors. (
  • All variants of plasmacytoma including plasmablastic myeloma stain positive and plasma cells dyscrasias such as monoclonal gammopathy of undetermined significance (MGUS). (
  • Conclusion We provided novel evidence that B cells differentiated within synovial ELS in the RA joints frequent target deiminated proteins which could be generated during NETosis of RA synovial neutrophils including histones. (
  • 1-6 Several post-translationally deiminated proteins have been indicated as a potential source of citrullinated antigens in the RA joints, 3 but to date their cellular source and specific contribution to the lesional ACPA response is unknown. (
  • Following contact with the host cell, the Ipa proteins IpaB and IpaC are inserted into the host plasma membrane by the type III secretion apparatus. (
  • Immunization with multiple variant antigens that have the same amino acid sequence at conserved positions on the viral spike proteins, but diverse amino acids at the surrounding positions, are likely to be required. (