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.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.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Receptors, Cell Surface: Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.Kinetics: The rate dynamics in chemical or physical systems.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.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.Taste Buds: Small sensory organs which contain gustatory receptor cells, basal cells, and supporting cells. Taste buds in humans are found in the epithelia of the tongue, palate, and pharynx. They are innervated by the CHORDA TYMPANI NERVE (a branch of the facial nerve) and the GLOSSOPHARYNGEAL NERVE.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.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.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.Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Antigens: Substances that are recognized by the immune system and induce an immune reaction.Sensory Receptor Cells: Specialized afferent neurons capable of transducing sensory stimuli into NERVE IMPULSES to be transmitted to the CENTRAL NERVOUS SYSTEM. Sometimes sensory receptors for external stimuli are called exteroceptors; for internal stimuli are called interoceptors and proprioceptors.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.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.T-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.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).Antigens, Bacterial: Substances elaborated by bacteria that have antigenic activity.Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.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.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.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.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.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.Taste: The ability to detect chemicals through gustatory receptors in the mouth, including those on the TONGUE; the PALATE; the PHARYNX; and the EPIGLOTTIS.Antigens, CD44: Acidic sulfated integral membrane glycoproteins expressed in several alternatively spliced and variable glycosylated forms on a wide variety of cell types including mature T-cells, B-cells, medullary thymocytes, granulocytes, macrophages, erythrocytes, and fibroblasts. CD44 antigens are the principle cell surface receptors for hyaluronate and this interaction mediates binding of lymphocytes to high endothelial venules. (From Abbas et al., Cellular and Molecular Immunology, 2d ed, p156)Recombinant Proteins: Proteins prepared by recombinant DNA technology.Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Receptors, Immunologic: Cell surface molecules on cells of the immune system that specifically bind surface molecules or messenger molecules and trigger changes in the behavior of cells. Although these receptors were first identified in the immune system, many have important functions elsewhere.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.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Endocytosis: Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.Ligands: A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)Protein Sorting Signals: Amino acid sequences found in transported proteins that selectively guide the distribution of the proteins to specific cellular compartments.Cell Adhesion Molecules: Surface ligands, usually glycoproteins, that mediate cell-to-cell adhesion. Their functions include the assembly and interconnection of various vertebrate systems, as well as maintenance of tissue integration, wound healing, morphogenic movements, cellular migrations, and metastasis.Cell Adhesion: Adherence of cells to surfaces or to other cells.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.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.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.Recombinant Fusion Proteins: Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.Bacterial Proteins: Proteins found in any species of bacterium.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Antigens, CD2: Glycoprotein members of the immunoglobulin superfamily which participate in T-cell adhesion and activation. They are expressed on most peripheral T-lymphocytes, natural killer cells, and thymocytes, and function as co-receptors or accessory molecules in the T-cell receptor complex.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.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.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.Mice, Inbred C57BLReceptors, 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.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.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.Epitopes: Sites on an antigen that interact with specific antibodies.Antigens, Differentiation, T-Lymphocyte: Antigens expressed on the cell membrane of T-lymphocytes during differentiation, activation, and normal and neoplastic transformation. Their phenotypic characterization is important in differential diagnosis and studies of thymic ontogeny and T-cell function.Antigens, CD34: Glycoproteins found on immature hematopoietic cells and endothelial cells. They are the only molecules to date whose expression within the blood system is restricted to a small number of progenitor cells in the bone marrow.Merozoite Surface Protein 1: A surface protein found on Plasmodium species which induces a T-cell response. The antigen is polymorphic, sharing amino acid sequence homology among PLASMODIUM FALCIPARUM; PLASMODIUM CHABAUDI; PLASMODIUM VIVAX; and PLASMODIUM YOELII.Receptors, Virus: Specific molecular components of the cell capable of recognizing and interacting with a virus, and which, after binding it, are capable of generating some signal that initiates the chain of events leading to the biological response.Molecular Weight: The sum of the weight of all the atoms in a molecule.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Proteins: Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.Antigens, CD19: Differentiation antigens expressed on B-lymphocytes and B-cell precursors. They are involved in regulation of B-cell proliferation.Antigens, CD28: Costimulatory T-LYMPHOCYTE receptors that have specificity for CD80 ANTIGEN and CD86 ANTIGEN. Activation of this receptor results in increased T-cell proliferation, cytokine production and promotion of T-cell survival.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.Mice, Inbred BALB CAntigens, Viral: Substances elaborated by viruses that have antigenic activity.Receptors, Antigen, T-Cell, alpha-beta: T-cell receptors composed of CD3-associated alpha and beta polypeptide chains and expressed primarily in CD4+ or CD8+ T-cells. Unlike immunoglobulins, the alpha-beta T-cell receptors recognize antigens only when presented in association with major histocompatibility (MHC) molecules.CHO Cells: CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.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.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.Peptides: Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.Protein Transport: The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Antigens, Protozoan: Any part or derivative of any protozoan that elicits immunity; malaria (Plasmodium) and trypanosome antigens are presently the most frequently encountered.Antigens, CD14: Glycolipid-anchored membrane glycoproteins expressed on cells of the myelomonocyte lineage including monocytes, macrophages, and some granulocytes. They function as receptors for the complex of lipopolysaccharide (LPS) and LPS-binding protein.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.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.Biotinylation: Incorporation of biotinyl groups into molecules.Antigens, Differentiation, B-Lymphocyte: Membrane antigens associated with maturation stages of B-lymphocytes, often expressed in tumors of B-cell origin.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.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.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.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.Mice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.Glycosylphosphatidylinositols: Compounds containing carbohydrate or glycosyl groups linked to phosphatidylinositols. They anchor GPI-LINKED PROTEINS or polysaccharides to cell membranes.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.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)Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Blotting, Western: Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.Olfactory Receptor Neurons: Neurons in the OLFACTORY EPITHELIUM with proteins (RECEPTORS, ODORANT) that bind, and thus detect, odorants. These neurons send their DENDRITES to the surface of the epithelium with the odorant receptors residing in the apical non-motile cilia. Their unmyelinated AXONS synapse in the OLFACTORY BULB of the BRAIN.Antigens, CD7: Differentiation antigens expressed on pluripotential hematopoietic cells, most human thymocytes, and a major subset of peripheral blood T-lymphocytes. They have been implicated in integrin-mediated cellular adhesion and as signalling receptors on T-cells.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).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.Glycosylation: The chemical or biochemical addition of carbohydrate or glycosyl groups to other chemicals, especially peptides or proteins. Glycosyl transferases are used in this biochemical reaction.Chorda Tympani Nerve: A branch of the facial (7th cranial) nerve which passes through the middle ear and continues through the petrotympanic fissure. The chorda tympani nerve carries taste sensation from the anterior two-thirds of the tongue and conveys parasympathetic efferents to the salivary glands.Olfactory Mucosa: That portion of the nasal mucosa containing the sensory nerve endings for SMELL, located at the dome of each NASAL CAVITY. The yellow-brownish olfactory epithelium consists of OLFACTORY RECEPTOR NEURONS; brush cells; STEM CELLS; and the associated olfactory glands.Bacterial Outer Membrane Proteins: Proteins isolated from the outer membrane of Gram-negative bacteria.Peptide Fragments: Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.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.Cell Line, Tumor: A cell line derived from cultured tumor cells.Binding, Competitive: The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.Lectins: Proteins that share the common characteristic of binding to carbohydrates. Some ANTIBODIES and carbohydrate-metabolizing proteins (ENZYMES) also bind to carbohydrates, however they are not considered lectins. PLANT LECTINS are carbohydrate-binding proteins that have been primarily identified by their hemagglutinating activity (HEMAGGLUTININS). However, a variety of lectins occur in animal species where they serve diverse array of functions through specific carbohydrate recognition.Microscopy, Fluorescence: Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.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).Immunoglobulin G: The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Jurkat Cells: A CELL LINE derived from human T-CELL LEUKEMIA and used to determine the mechanism of differential susceptibility to anti-cancer drugs and radiation.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, 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.Lectins, C-Type: A class of animal lectins that bind to carbohydrate in a calcium-dependent manner. They share a common carbohydrate-binding domain that is structurally distinct from other classes of lectins.CD4-CD8 Ratio: Ratio of T-LYMPHOCYTES that express the CD4 ANTIGEN to those that express the CD8 ANTIGEN. This value is commonly assessed in the diagnosis and staging of diseases affecting the IMMUNE SYSTEM including HIV INFECTIONS.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.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.H-2 Antigens: The major group of transplantation antigens in the mouse.Calcium: A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.Pre-B Cell Receptors: Membrane proteins in precursor B-LYMPHOCYTES (pre-B Cells). They are composed of membrane-bound MU IMMUNOGLOBULIN HEAVY CHAINS in complex with SURROGATE LIGHT CHAINS instead of conventional IMMUNOGLOBULIN LIGHT CHAINS. Only successful rearrangement of the VDJ segments, at the Ig heavy chain gene locus (IMMUNOGLOBULIN HEAVY CHAIN GENES), will generate mu heavy chains that can pair with surrogate light chains. Thus formation of the pre-B cell receptors is an important checkpoint in the development of mature B cells.Amino Acid Motifs: Commonly observed structural components of proteins formed by simple combinations of adjacent secondary structures. A commonly observed structure may be composed of a CONSERVED SEQUENCE which can be represented by a CONSENSUS SEQUENCE.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.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.Precipitin Tests: Serologic tests in which a positive reaction manifested by visible CHEMICAL PRECIPITATION occurs when a soluble ANTIGEN reacts with its precipitins, i.e., ANTIBODIES that can form a precipitate.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.CD8-Positive T-Lymphocytes: A critical subpopulation of regulatory T-lymphocytes involved in MHC Class I-restricted interactions. They include both cytotoxic T-lymphocytes (T-LYMPHOCYTES, CYTOTOXIC) and CD8+ suppressor T-lymphocytes.HeLa Cells: The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.Antigens, Differentiation, Myelomonocytic: Surface antigens expressed on myeloid cells of the granulocyte-monocyte-histiocyte series during differentiation. Analysis of their reactivity in normal and malignant myelomonocytic cells is useful in identifying and classifying human leukemias and lymphomas.Immunophenotyping: 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.Antigens, CD56: The 140 kDa isoform of NCAM (neural cell adhesion molecule) containing a transmembrane domain and short cytoplasmic tail. It is expressed by all lymphocytes mediating non-MHC restricted cytotoxicity and is present on some neural tissues and tumors.Down-Regulation: A negative regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.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.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)DNA, Complementary: Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.Cytoplasm: The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)COS Cells: CELL LINES derived from the CV-1 cell line by transformation with a replication origin defective mutant of SV40 VIRUS, which codes for wild type large T antigen (ANTIGENS, POLYOMAVIRUS TRANSFORMING). They are used for transfection and cloning. (The CV-1 cell line was derived from the kidney of an adult male African green monkey (CERCOPITHECUS AETHIOPS).)Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Protein Processing, Post-Translational: Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.Bacterial Adhesion: Physicochemical property of fimbriated (FIMBRIAE, BACTERIAL) and non-fimbriated bacteria of attaching to cells, tissue, and nonbiological surfaces. It is a factor in bacterial colonization and pathogenicity.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, 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.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, CD24: A cell adhesion protein that was originally identified as a heat stable antigen in mice. It is involved in METASTASIS and is highly expressed in many NEOPLASMS.Immunoblotting: Immunologic method used for detecting or quantifying immunoreactive substances. The substance is identified by first immobilizing it by blotting onto a membrane and then tagging it with labeled antibodies.Cell SeparationADP-ribosyl Cyclase: A membrane-bound or cytosolic enzyme that catalyzes the synthesis of CYCLIC ADP-RIBOSE (cADPR) from nicotinamide adenine dinucleotide (NAD). This enzyme generally catalyzes the hydrolysis of cADPR to ADP-RIBOSE, as well, and sometimes the synthesis of cyclic ADP-ribose 2' phosphate (2'-P-cADPR) from NADP.DNA Primers: Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.Antigens, CD9: A subtype of tetraspanin proteins that play a role in cell adhesion, cell motility, and tumor metastasis. CD9 antigens take part in the process of platelet activation and aggregation, the formation of paranodal junctions in neuronal tissue, and the fusion of sperm with egg.Cercopithecus aethiops: A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.Integrins: A family of transmembrane glycoproteins (MEMBRANE GLYCOPROTEINS) consisting of noncovalent heterodimers. They interact with a wide variety of ligands including EXTRACELLULAR MATRIX PROTEINS; COMPLEMENT, and other cells, while their intracellular domains interact with the CYTOSKELETON. The integrins consist of at least three identified families: the cytoadhesin receptors(RECEPTORS, CYTOADHESIN), the leukocyte adhesion receptors (RECEPTORS, LEUKOCYTE ADHESION), and the VERY LATE ANTIGEN RECEPTORS. Each family contains a common beta-subunit (INTEGRIN BETA CHAINS) combined with one or more distinct alpha-subunits (INTEGRIN ALPHA CHAINS). These receptors participate in cell-matrix and cell-cell adhesion in many physiologically important processes, including embryological development; HEMOSTASIS; THROMBOSIS; WOUND HEALING; immune and nonimmune defense mechanisms; and oncogenic transformation.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.Microscopy, Confocal: A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.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.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Reverse Transcriptase Polymerase Chain Reaction: A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.Antigens, CD53: Tetraspanin proteins found at high levels in cells of the lymphoid-myeloid lineage. CD53 antigens may be involved regulating the differentiation of T-LYMPHOCYTES and the activation of B-LYMPHOCYTES.Cricetulus: A genus of the family Muridae consisting of eleven species. C. migratorius, the grey or Armenian hamster, and C. griseus, the Chinese hamster, are the two species used in biomedical research.Spleen: An encapsulated lymphatic organ through which venous blood filters.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.)Antigens, CD13: Zinc-binding metalloproteases that are members of the type II integral membrane metalloproteases. They are expressed by GRANULOCYTES; MONOCYTES; and their precursors as well as by various non-hematopoietic cells. They release an N-terminal amino acid from a peptide, amide or arylamide.Adhesins, Bacterial: Cell-surface components or appendages of bacteria that facilitate adhesion (BACTERIAL ADHESION) to other cells or to inanimate surfaces. Most fimbriae (FIMBRIAE, BACTERIAL) of gram-negative bacteria function as adhesins, but in many cases it is a minor subunit protein at the tip of the fimbriae that is the actual adhesin. In gram-positive bacteria, a protein or polysaccharide surface layer serves as the specific adhesin. What is sometimes called polymeric adhesin (BIOFILMS) is distinct from protein adhesin.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Protozoan Proteins: Proteins found in any species of protozoan.Biological Transport: The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Fibronectins: Glycoproteins found on the surfaces of cells, particularly in fibrillar structures. The proteins are lost or reduced when these cells undergo viral or chemical transformation. They are highly susceptible to proteolysis and are substrates for activated blood coagulation factor VIII. The forms present in plasma are called cold-insoluble globulins.DNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).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.Epithelial Cells: Cells that line the inner and outer surfaces of the body by forming cellular layers (EPITHELIUM) or masses. Epithelial cells lining the SKIN; the MOUTH; the NOSE; and the ANAL CANAL derive from ectoderm; those lining the RESPIRATORY SYSTEM and the DIGESTIVE SYSTEM derive from endoderm; others (CARDIOVASCULAR SYSTEM and LYMPHATIC SYSTEM) derive from mesoderm. Epithelial cells can be classified mainly by cell shape and function into squamous, glandular and transitional epithelial cells.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.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.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.Tongue: A muscular organ in the mouth that is covered with pink tissue called mucosa, tiny bumps called papillae, and thousands of taste buds. The tongue is anchored to the mouth and is vital for chewing, swallowing, and for speech.Receptors, Transferrin: Membrane glycoproteins found in high concentrations on iron-utilizing cells. They specifically bind iron-bearing transferrin, are endocytosed with its ligand and then returned to the cell surface where transferrin without its iron is released.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.Solubility: The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Receptors, G-Protein-Coupled: The largest family of cell surface receptors involved in SIGNAL TRANSDUCTION. They share a common structure and signal through HETEROTRIMERIC G-PROTEINS.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.Killer Cells, Natural: Bone marrow-derived lymphocytes that possess cytotoxic properties, classically directed against transformed and virus-infected cells. Unlike T CELLS; and B CELLS; NK CELLS are not antigen specific. The cytotoxicity of natural killer cells is determined by the collective signaling of an array of inhibitory and stimulatory CELL SURFACE RECEPTORS. A subset of T-LYMPHOCYTES referred to as NATURAL KILLER T CELLS shares some of the properties of this cell type.GPI-Linked Proteins: A subclass of lipid-linked proteins that contain a GLYCOSYLPHOSPHATIDYLINOSITOL LINKAGE which holds them to the CELL MEMBRANE.Chemoreceptor Cells: Cells specialized to detect chemical substances and relay that information centrally in the nervous system. Chemoreceptor cells may monitor external stimuli, as in TASTE and OLFACTION, or internal stimuli, such as the concentrations of OXYGEN and CARBON DIOXIDE in the blood.Necturus: A genus of the Proteidae family with five recognized species, which inhabit the Atlantic and Gulf drainages.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.Cytotoxicity, Immunologic: The phenomenon of target cell destruction by immunologically active effector cells. It may be brought about directly by sensitized T-lymphocytes or by lymphoid or myeloid "killer" cells, or it may be mediated by cytotoxic antibody, cytotoxic factor released by lymphoid cells, or complement.Antigens, CD47: A ubiquitously expressed membrane glycoprotein. It interacts with a variety of INTEGRINS and mediates responses to EXTRACELLULAR MATRIX PROTEINS.Tyrosine: A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.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.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).Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Epithelium: One or more layers of EPITHELIAL CELLS, supported by the basal lamina, which covers the inner or outer surfaces of the body.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.Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Antigens, CD29: Integrin beta-1 chains which are expressed as heterodimers that are noncovalently associated with specific alpha-chains of the CD49 family (CD49a-f). CD29 is expressed on resting and activated leukocytes and is a marker for all of the very late activation antigens on cells. (from: Barclay et al., The Leukocyte Antigen FactsBook, 1993, p164)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.Antigens, CD36: Leukocyte differentiation antigens and major platelet membrane glycoproteins present on MONOCYTES; ENDOTHELIAL CELLS; PLATELETS; and mammary EPITHELIAL CELLS. They play major roles in CELL ADHESION; SIGNAL TRANSDUCTION; and regulation of angiogenesis. CD36 is a receptor for THROMBOSPONDINS and can act as a scavenger receptor that recognizes and transports oxidized LIPOPROTEINS and FATTY ACIDS.Membrane Microdomains: Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins.
... homing cell adhesion molecule), Pgp-1 (phagocytic glycoprotein-1), Hermes antigen, lymphocyte homing receptor, ECM-III, and ... The CD44 antigen is a cell-surface glycoprotein involved in cell-cell interactions, cell adhesion and migration. In humans, the ... HCELL functions as a "bone homing receptor", directing migration of human hematopoietic stem cells and mesenchymal stem cells ... The protein is a determinant for the Indian blood group system. CD44, along with CD25, is used to track early T cell ...
... has received signal one and signal two) it alters its cell surface expression of a variety of proteins. Markers of T cell ... NKT cells recognize glycolipid antigen presented by a molecule called CD1d. Once activated, these cells can perform functions ... They also have intermediate to high expression of CD44. These memory T cells lack lymph node-homing receptors and are thus ... This coupled with NFAT signaling allows for complete activation of the IL-2 gene. While in most cases activation is dependent ...
A group of diencephalic cells that express the cell surface antigen stage-specific embryonic antigen (SSEA)-1 and CD44 will ... the principal receptor for Shh, mediated signaling. RGCs exit the retinal ganglion cell layer through the optic disc, which ... "Embryonic neurons of the developing optic chiasm express L1 and CD44, cell surface molecules with opposing effects on retinal ... Based on their projections and functions, there are at least five main classes of retinal ganglion cells: Midget cell ( ...
... tissue after signal transduction via respective G protein-coupled receptors that activates integrins on the leukocyte surface ... The function of inflammation is to eliminate the initial cause of cell injury, clear out necrotic cells and tissues damaged ... Upregulation of anti-inflammatory molecules such as the interleukin 1 receptor antagonist or the soluble tumor necrosis factor ... Cell Communication and Signaling. 9 (18). doi:10.1186/1478-811X-9-18. PMC 3180438 . PMID 21914164. Coussens, L. M.; Werb, Z. ( ...
... cell by down-regulating expression of its CD8 cell surface receptors. If the cell does not lose its signal, it will continue ... NKT cells recognize glycolipid antigen presented by a molecule called CD1d. Once activated, these cells can perform functions ... has received signal one and signal two) it alters its cell surface expression of a variety of proteins. Markers of T cell ... They also have intermediate to high expression of CD44. These memory T cells lack lymph node-homing receptors and are thus ...
The ability of T cells to recognize foreign antigens is mediated by the T cell receptor (TCR), which is a surface protein able ... receive signalling through the T cell receptor. Thymocytes that have a T cell receptor incapable of binding MHC class I or ... The primary function of thymocytes is the generation of T lymphocytes (T cells). The thymus provides an inductive environment, ... Molecules known to be important for thymus entry include P-selectin (CD62P), and the chemokine receptors CCR7 and CCR9. ...
Leukosialin also known as sialophorin or CD43 (cluster of differentiation 43) is a transmembrane cell surface protein that in ... 2001). "Cutting edge: CD43 functions as a T cell counterreceptor for the macrophage adhesion receptor sialoadhesin (Siglec-1 ... "T cell activation through the CD43 molecule leads to Vav tyrosine phosphorylation and mitogen-activated protein kinase pathway ... proteins bind to a positively charged amino acid cluster in the juxta-membrane cytoplasmic domain of CD44, CD43, and ICAM-2". J ...
... cell by down-regulating expression of its CD8 cell surface receptors. If the cell does not lose its signal, it will continue ... molecules, NKT cells recognize glycolipid antigen presented by CD1d. Once activated, these cells can perform functions ascribed ... has received signal one and signal two) it alters its cell surface expression of a variety of proteins. Markers of T cell ... The newly arrived CLP cells are CD4-CD8-CD44+CD25-ckit+ cells, and are termed early thymic progenitors (ETP) cells.[3] These ...
Normal integrin is a cell surface receptor that interacts with the extracellular matrix to send signals influencing cell shape ... and/or to generate a binding site on the target protein that recruits other signaling molecules. Interestingly, Fyn also has ... integrin-mediated signaling, growth factor and cytokine receptor signaling, platelet activation, ion channel function, cell ... "Src-related protein tyrosine kinases are physically associated with the surface antigen CD36 in human dermal microvascular ...
... of epidermal growth factor receptor and associated signaling proteins is regulated by cell density in IEC-6 intestinal cells". ... signal molecules can no longer attach there and activate the tyrosine kinase. Another method is using small molecules to ... Smad target gene protein tyrosine phosphatase receptor type kappa is required for TGF-{beta} function". Molecular and Cellular ... Epidermal growth factor receptor has been shown to interact with: AR, ARF4, CAV1, CAV3, CBL, CBLB, CBLC, CD44, CDC25A, CRK, ...
... to receptors that trigger events inside the cell. The binding of a signaling molecule with a receptor causes a change in the ... "Mechanisms of regulation and function of G-protein-coupled receptor kinases". World J Gastroenterol. 12 (48): 7753-7. doi: ... "Single-molecule imaging of EGFR signalling on the surface of living cells". Nature Cell Biology. 2 (3): 168-72. doi:10.1038/ ... an indicator of antigen-induced signal transduction in antigen-binding cells". Journal of Immunology. 122 (4): 1278-84. PMID ...
cell surface receptor signaling pathway. • positive regulation of natural killer cell mediated cytotoxicity. • antigen ... is a cell surface molecule with diverse biologic effects on T cell function. It is an immune checkpoint receptor and as such is ... "MHC class II signal transduction in human dendritic cells induced by a natural ligand, the LAG-3 protein (CD223)". Blood. 102 ( ... Molecular function. • antigen binding. • transmembrane signaling receptor activity. • MHC class II protein binding. ...
Accessory molecule (CD79) Ig-α (CD79A) Ig-β (CD79B) T cells Antigen receptor - T cell receptor (TCR) Subunits - [email protected] / [email protected] / ... Treg differentiation JAK-STAT signaling pathway TGF beta signaling pathway TLR signalling pathway Cell adhesion molecules ... LTi cells) (Non-hematopoietic cells with immune functions) Stromal cells Lymph node stromal cells Follicular dendritic cells ... 7-transmembrane G protein-coupled receptors CC chemokine receptors (CCRs) CXC chemokine receptors (CXCRs) C chemokine receptors ...
Early apoptotic cells express "eat-me" signals, of cell-surface proteins such as phosphatidylserine, that prompt immune cells ... from whole blood of people with SLE show reduced expression of CD44 surface molecules involved in the uptake of apoptotic cells ... due to their affinity for self-tissues can be abnormally activated by signaling sequences of antigen-presenting cells. Thus ... The clearance of early apoptotic cells is an important function in multicellular organisms. It leads to a progression of the ...
T cell helper function in human cells which characterized the 32 kDa surface protein transiently expressed on CD4+ T cells.[9] ... Receptor/signaling modulators. Signaling peptide/protein receptor modulators. Growth factor receptor modulators. ... Roles of T cell-B-cell-activating molecule (5c8 antigen) and CD40 in contact-dependent help". Journal of Immunology. 149 (12): ... The secondary signal is CD40L on the T cell, which binds CD40 on the macrophage cell surface. As a result, the macrophage ...
enzyme linked receptor protein signaling pathway. • entry into host cell. • T cell activation. • positive regulation of T cell ... T cells displaying CD4 molecules (and not CD8) on their surface, therefore, are specific for antigens presented by MHC II and ... Function[edit]. CD4 is a co-receptor of the T cell receptor (TCR) and assists the latter in communicating with antigen- ... T-helper cells or T4 cells. They are called helper cells because one of their main roles is to send signals to other types of ...
Rönnstrand L (2004). „Signal transduction via the stem cell factor receptor/c-Kit". Cell. Mol. Life Sci. 61 (19-20): 2535-2548 ... 2003). „Signal transduction-associated and cell activation-linked antigens expressed in human mast cells". Int. J. Hematol. 75 ... a new cell surface receptor tyrosine kinase for an unidentified ligand". EMBO J. 6 (11): 3341-51. PMC 553789 . PMID 2448137.. ... Linnekin D (2000). „Early signaling pathways activated by c-Kit in hematopoietic cells". Int. J. Biochem. Cell Biol. 31 (10): ...
receptor activity. • antigen binding. • virus receptor activity. • protein binding. • transmembrane signaling receptor activity ... STAT6, IRF4, and NF-kB factors involved in the transfer of the signals from the B-cell receptor, its co-receptors and IL-4R, ... Signaling lymphocytic activation molecule 1 is a protein that in humans is encoded by the SLAMF1 gene.[5][6] Recently SLAMF1 ... Del Valle JM, Engel P, Martín M (2003). "The cell surface expression of SAP-binding receptor CD229 is regulated via its ...
cell-cell signaling. • G-protein coupled receptor signaling pathway. • cell surface receptor signaling pathway. • movement of ... "Expression cloning and chromosomal mapping of the leukocyte activation antigen CD97, a new seven-span transmembrane molecule of ... G-protein coupled receptor activity. • protein binding. • transmembrane signaling receptor activity. • signal transducer ... Function[edit]. In the immune system, CD97 is known as a critical mediator of host defense. Upon lymphoid, myeloid cells and ...
"Endothelial cell E- and P-selectin and vascular cell adhesion molecule-1 function as signaling receptors". J. Cell Biol. 142 ... The elevated synthesis of P-selectin may play an important role in the delivery of protein to the cell surface. In ischemic ... Lymphocyte homing receptor: CD44. *L-selectin. *integrin (VLA-4, LFA-1). *Carcinoembryonic antigen ... "Cytoplasmic domain of P-selectin (CD62) contains the signal for sorting into the regulated secretory pathway". Mol. Biol. Cell ...
... is a protein that in humans is encoded by the VCAM1 gene.[5] VCAM-1 functions as a cell adhesion molecule. ... Lymphocyte homing receptor: CD44. *L-selectin. *integrin (VLA-4, LFA-1). *Carcinoembryonic antigen ... cell-cell adhesion. • cytokine-mediated signaling pathway. • heterotypic cell-cell adhesion. • innervation. • cardiac neuron ... apical part of cell. • microvillus. • cell surface. • early endosome. • endoplasmic reticulum. • podosome. • sarcolemma. • ...
Dual specificity mitogen-activated protein kinase kinase 2 is an enzyme that in humans is encoded by the MAP2K2 gene. It is more commonly known as MEK2, but has many alternative names including CFC4, MKK2, MAPKK2 and PRKMK2. The protein encoded by this gene is a dual specificity protein kinase that belongs to the MAP kinase kinase family. This kinase is known to play a critical role in mitogen growth factor signal transduction. It phosphorylates and thus activates MAPK1/ERK2 and MAPK3/ERK1. The activation of this kinase itself is dependent on the Ser/Thr phosphorylation by MAP kinase kinase kinases. The inhibition or degradation of this kinase is found to be involved in the pathogenesis of Yersinia and anthrax. MAP2K2 has been shown to interact with MAPK3 and ARAF. GRCh38: Ensembl release 89: ENSG00000126934 - Ensembl, May 2017 GRCm38: Ensembl release 89: ENSMUSG00000035027 - Ensembl, May 2017 "Human PubMed Reference:". "Mouse PubMed Reference:". Zheng CF, ...
... , commonly abbreviated to PKC (EC 2.7.11.13), is a family of protein kinase enzymes that are involved in controlling the function of other proteins through the phosphorylation of hydroxyl groups of serine and threonine amino acid residues on these proteins, or a member of this family. PKC enzymes in turn are activated by signals such as increases in the concentration of diacylglycerol (DAG) or calcium ions (Ca2+). Hence PKC enzymes play important roles in several signal transduction cascades. The PKC family consists of fifteen isozymes in humans. They are divided into three subfamilies, based on their second messenger requirements: conventional (or classical), novel, and atypical. Conventional (c)PKCs contain the isoforms α, βI, βII, and γ. These require Ca2+, DAG, and a phospholipid such as phosphatidylserine for activation. Novel (n)PKCs include the δ, ε, η, and θ isoforms, and require DAG, but do not require Ca2+ for activation. Thus, ...
... s (GPCRs) which are also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptor, and G protein-linked receptors (GPLR), constitute a large protein family of receptors that detect molecules outside the cell and activate internal signal transduction pathways and, ultimately, cellular responses. Coupling with G proteins, they are called seven-transmembrane receptors because they pass through the ...
The function of receptor-mediated endocytosis is diverse. It is widely used for the specific uptake of certain substances required by the cell (examples include LDL via the LDL receptor or iron via transferrin). The role of receptor-mediated endocytosis is well recognized up take downregulation of transmembrane signal transduction but can also promote sustained signal transduction.[3] The activated receptor becomes internalised and is transported to late endosomes and lysosomes for degradation. However, receptor-mediated endocytosis is also actively implicated in transducing signals from the cell periphery to the nucleus. This became ...
The PI3K/AKT/mTOR pathway is an intracellular signaling pathway important in regulating the cell cycle. Therefore, it is directly related to cellular quiescence, proliferation, cancer, and longevity. PI3K activation phosphorylates and activates AKT, localizing it in the plasma membrane. AKT can have a number of downstream effects such as activating CREB, inhibiting p27, localizing FOXO in the cytoplasm, activating PtdIns-3ps, and activating mTOR which can affect transcription of p70 or 4EBP1. There are many known factors that enhance the PI3K/AKT pathway including EGF, shh, IGF-1, insulin, and CaM. The pathway is antagonized by various factors including PTEN, GSK3B, and HB9. In many cancers, this pathway is overactive, thus reducing apoptosis and allowing proliferation. This pathway is necessary, however, to promote growth and proliferation ...
GTPase HRas also known as transforming protein p21 is an enzyme that in humans is encoded by the HRAS gene. The HRAS gene is located on the short (p) arm of chromosome 11 at position 15.5, from base pair 522,241 to base pair 525,549. HRas is a small G protein in the Ras subfamily of the Ras superfamily of small GTPases. Once bound to Guanosine triphosphate, H-Ras will activate a Raf kinase like c-Raf, the next step in the MAPK/ERK pathway. GTPase HRas is involved in regulating cell division in response to growth factor stimulation. Growth factors act by binding cell surface receptors that span the cell's plasma membrane. Once activated, receptors stimulate signal transduction events in the ...
... is an enzyme that in humans is encoded by the LTK gene. The protein encoded by this gene is a member of the ALK/LTK receptor family of receptor tyrosine kinases (RTKs) whose ligand is unknown. Closely related to the insulin receptor family of RTKs. Tyrosine-specific phosphorylation of proteins is a key to the control of diverse pathways leading to cell growth and differentiation. Two alternatively spliced transcript variants encoding different isoforms have been described for this gene. LTK has been shown to interact with IRS-1, Shc, and PIK3R1. GRCh38: Ensembl release 89: ENSG00000062524 - Ensembl, May 2017 GRCm38: Ensembl release 89: ENSMUSG00000027297 - Ensembl, May 2017 "Human PubMed Reference:". "Mouse PubMed Reference:". Maru Y, Hirai H, Takaku F (May 1990). ...
Activated CDC42 kinase 1, also known as ACK1, is an enzyme that in humans is encoded by the TNK2 gene. TNK2 gene encodes a non-receptor tyrosine kinase, ACK1, that binds to multiple receptor tyrosine kinases e.g. EGFR, MERTK, AXL, HER2 and insulin receptor (IR). ACK1 also interacts with Cdc42Hs in its GTP-bound form and inhibits both the intrinsic and GTPase-activating protein (GAP)-stimulated GTPase activity of Cdc42Hs. This binding is mediated by a unique sequence of 47 amino acids C-terminal to an SH3 domain. The protein may be involved in a regulatory mechanism that sustains the GTP-bound active form of Cdc42Hs and which is directly linked to a tyrosine phosphorylation signal transduction pathway. Several alternatively spliced transcript variants have ...
Calcineurin subunit B type 2 is a protein that in humans is encoded by the PPP3R2 gene. Among its related pathways are MAPK signaling pathway and GPCR pathway. GO annotations related to this gene include calcium ion binding. An important paralog of this gene is CHP1. GRCh38: Ensembl release 89: ENSG00000188386 - Ensembl, May 2017 GRCm38: Ensembl release 89: ENSMUSG00000028310 - Ensembl, May 2017 "Human PubMed Reference:". "Mouse PubMed Reference:". Liu L, Zhang J, Yuan J, Dang Y, Yang C, Chen X, Xu J, Yu L (May 2005). "Characterization of a human regulatory subunit of protein phosphatase 3 gene (PPP3RL) expressed specifically in testis". Mol Biol Rep. 32 (1): 41-5. doi:10.1007/s11033-004-4250-4. PMID 15865209. "Entrez Gene: PPP3R2 protein phosphatase 3 (formerly 2B), regulatory subunit B, beta isoform". "PathCards :: MAPK signaling pathway Pathway and related pathways". pathcards.genecards.org. Retrieved 2015-09-08. ...
A co-receptor is a cell surface receptor that binds a signalling molecule in addition to a primary receptor in order to facilitate ligand recognition and initiate biological processes, such as entry of a pathogen into a host cell. The term co-receptor is prominent in literature regarding signal transduction, the process by which external stimuli regulate internal cellular functioning. The key to optimal cellular functioning is maintained by possessing specific machinery that can carry out tasks efficiently and effectively. Specifically, the process through which ...
Protein Tob1 is a protein that in humans is encoded by the TOB1 gene. This gene encodes a member of the tob/btg1 family of anti-proliferative proteins that have the potential to regulate cell growth. When exogenously expressed, this protein suppresses cell growth in tissue culture. The protein undergoes phosphorylation by a serine/threonine kinase, 90 kDa ribosomal S6 kinase. Interactions of this protein with the v-erb-b2 erythroblastic leukemia viral oncogene homolog 2 gene product p185 interferes with growth suppression. This protein inhibits T cell proliferation and transcription of cytokines and cyclins. The protein interacts with both mothers against decapentaplegic Drosophila homolog 2 and 4 to enhance their DNA ...
This receptor is expressed by activated, but not by resting, T and B cells. TRAF2 and TRAF5 can interact with this receptor, and mediate the signal transduction that leads to the activation of NF-kappaB. It is a positive regulator of apoptosis, and also has been shown to limit the proliferative potential of autoreactive CD8 effector T cells and protect the body against autoimmunity. Two alternatively spliced transcript variants of this gene encoding distinct isoforms have been reported.[5] ...
Akt1通过抑制凋亡过程从而参与细胞存活途径。Akt1亦能诱导蛋白合成通路,故其在导致骨骼肌肥大及的一般组织生长的细胞通路中是一种重要信号蛋白。因其可以阻断凋亡并继而促进细胞存活,现已表明Akt1在多种肿瘤中起到主要作用。Akt(先亦被称为Akt1)首先是在转化逆转录病毒AKT8中被鉴定为癌基因的[3]。 Akt2在胰岛素信号通路中是一重要的信号分子。需要其来诱导葡萄糖转运。在敲除Akt1但具正常Akt2的小鼠中,血糖稳态不受干扰,但动物体型会较小,这与Akt1在生长中起得作用是一致的。相反,Akt2缺失但具有正常Akt1的的小鼠生长略缺陷且表现出糖尿病表型(胰岛素抵抗),这从另一方面印证了Akt2对胰岛素受体信号通路更具特异性的这一设想[4]。 Akt3似乎主要在脑中表达,但其作用仍未明晰。有报道显示Akt3缺失的小鼠脑部较小[5]。 ...
... years has characterized the T cell surface molecule CD26 as a receptor capable of generating T cell costimulatory signals (8, 9 ... with no intrinsic protein tyrosine kinase function nor known binding motif for tyrosine kinases. Addressing this issue, our ... with the second signal being provided by other receptor-ligand interactions between T cells and antigen-presenting cells (6, 7 ... and CD44) (17). In view of the ability of CD26 to serve as a costimulatory molecule for the CD3/TCR pathway of activation, we ...
... in tandem with costimulation with the signaling lymphocyte activation-molecule family receptor Ly108 (18), leads to high PLZF ... CD44low) iNKT cells. This finding is further exemplified by the enrichment for CD44low NK1.1− cells in the spleen and for NK1.1 ... Furthermore, this iNKT cell self-reactivity appears to be an intrinsic component of their immune functions (8⇓-10). ... During iNKT cell positive selection, agonistic TCR signals are associated with high expression of the Ras- (15) and Ca2+- ...
... cells are innate-like T lymphocytes that recognize glycolipid antigens presented by the MHC class I-like protein CD1d. ... This property of NKT cells, in conjunction with their interactions with antigen-presenting cells, controls downstream innate ... This property of NKT cells, in conjunction with their interactions with antigen-presenting cells, controls downstream innate ... NKT cell properties are acquired during development in the thymus and by interactions with the host microbial consortium in the ...
ERM proteins regulate the linkage of cortical actin to membrane-associated proteins in cellular... ... Cytovillin; p81; Villin-2 The ERM family of proteins is composed of Ezrin, Radixin, and Moesin. ... Functional nanoscale organization of signaling molecules downstream of the T cell antigen receptor. Immunity. 2011;35(5):705-20 ... ERM family members as molecular linkers between the cell surface glycoprotein CD44 and actin-based cytoskeletons. J Cell Biol. ...
Besides serving as a harbor for the unwanted material exocytosed by cells, EVs play a critical role in conveying intact protein ... The final section of this review discusses how the biological properties of immune cell-derived sEVs can be manipulated to ... The final section of this review discusses how the biological properties of immune cell-derived sEVs can be manipulated to ... Exosomes are 40-150 nm, endosome-derived small EVs (sEVs) that are released by cells into the extracellular environment. This ...
... by the T cell receptor (TCR) on T cells [10-19]. T cells constantly scan the APC surface searching for antigens to activate and ... of T-cell receptor signal transduction and viral expression by the linker for activation of T cells-interacting p12I protein of ... M. Iwashima, "Kinetic perspectives of T cell antigen receptor signaling: a two-tier model for T cell full activation," ... malignant cells could avoid T cell effector functions by antagonizing T-cell activation after expressing surface ligands that ...
... has received signal one and signal two) it alters its cell surface expression of a variety of proteins. Markers of T cell ... NKT cells recognize glycolipid antigen presented by a molecule called CD1d. Once activated, these cells can perform functions ... They also have intermediate to high expression of CD44. These memory T cells lack lymph node-homing receptors and are thus ... This coupled with NFAT signaling allows for complete activation of the IL-2 gene. While in most cases activation is dependent ...
... biological response modifiers and the family of cell adhesion-promoting molecules. ... and both cell surface and cytoplasmic expression of CTLA4 (the coinhibitory receptor cytotoxic T lymphocyte antigen 4) [11, 19 ... CD44, CD28 (costimulatory molecule), CCR7 (chemokine (C-C motif) receptor 7), CXCR4, OX40 (CD134), Folate receptor-4 [28], and ... O. Micheau and J. Tschopp, "Induction of TNF receptor I-mediated apoptosis via two sequential signaling complexes," Cell, vol. ...
... homing cell adhesion molecule), Pgp-1 (phagocytic glycoprotein-1), Hermes antigen, lymphocyte homing receptor, ECM-III, and ... The CD44 antigen is a cell-surface glycoprotein involved in cell-cell interactions, cell adhesion and migration. In humans, the ... HCELL functions as a "bone homing receptor", directing migration of human hematopoietic stem cells and mesenchymal stem cells ... The protein is a determinant for the Indian blood group system. CD44, along with CD25, is used to track early T cell ...
In addition, ICAM-1 might function as cell-surface receptor, capable of initiating intracellular signaling. ICAM-1 is ... ve T cell activation requires the interactions of antigen receptors, adhesion molecules and co-stimulatory molecules. Antigen ... cell communication and cell signalling, governing protein interactions and protein aggregation. ... endothelial cells, and blockade of CD11b and CD44 diminishes monocyte localization to these hepatic foci. Our studies ...
... including cell signaling through Toll-like receptors, inflammation, and T cell recruitment via interactions with CD44 (64), its ... The clearance and immunogenicity of molecules can be affected not only by the expression of endocytic cell surface receptors, ... Antigen-presenting function and B7 expression of murine sinusoidal endothelial cells and Kupffer cells. Gastroenterology. 1996; ... In addition to facilitating protein clearance, binding of VWF-FVIII to endocytic receptors can regulate interactions with cells ...
T cells, induced pluripotent stem cells, differentiation, Notch signaling, T cell receptor, adoptive cell transfer ... antigen-driven membrane transfer9 and/or precursor cell proliferation3,4,10-18 and immune regulatory and effector cell function ... the adhesive interaction of cell surface integrins with ligands expressed on other cells or with extracellular matrix proteins ... the molecules and signaling pathways that control differentiation are largely unknown. Primary T cells can be manipulated ...
It interacts with many cell surface receptors including integrins and CD44. One of the major physiologic functions of OPN is ... Platelet Derived Growth Factor (PDGF), which is secreted by carcinoma cells, is the most important signaling molecule to ... CARMA - Chimeric Antigen Receptor Macrophages 1 Reply CARMA Therapeutics, a company that develops chimeric antigen receptor ... Osteopontin (OPN) is a matrix protein that is expressed by osteoclasts, osteoblasts, dendritic cells, fibroblasts, hepatocytes ...
CD4(+) memory cell development is dependent upon T cell receptor (TCR) signal strength, antigen dose and the cytokine milieu, ... from CD44 knockout mice demonstrated impaired regulatory function ex vivo and depressed production of IL-10 and cell surface ... The Toll-Like Receptor Signaling Molecule Myd88 Contributes to Pancreatic Beta-Cell Homeostasis in Response to Injury PLOS ONE ... "keystone molecule" in the inflammatory milieu and that HA, together with its associated binding proteins and receptors, is an ...
CD44high, Ly6C+) are more sensitive than naive cells (CD44low, Ly6C−) to TCR/CD8 signaling in response to antigen. J. Immunol. ... Artificial cell surface constructs for studying receptor-ligand contributions to lymphocyte activation. J. Immunol. Methods 209 ... IL-12 is required for development of lytic effector function of CD8+CD44low T cells. Purified naive CD8+CD44low T cells from OT ... MHC protein/peptide Ag complexes immobilized on inert microspheres can be used to study T cell activation requirements in the ...
... and their associated proteins identified. These proteins include transmembrane... ... Gauld, S., Dal, P.J., and Cambier, J. [ 2002 ]. B cell antigen receptor signaling: Roles in cell development and disease. ... S-acylation of LCK protein tyrosine kinase is essential for its signalling function in T lymphocytes. Embo J. 16: 4983-4998. ... T cell antigen receptor (TCR) transmembrane peptides colocalize with TCR, not lipid rafts, in surface membranes. Cell Immunol. ...
... stromal cell-derived factor 1 receptor , CXC chemokine receptor , LESTR , chemokine receptor (LCR1) , CD184 antigen , leukocyte ... function and expression of adhesion-related molecules through the CXCL12 (zeige CXCL12 Antikörper)/CXCR4 signalling pathway. ... The protein has 7 transmembrane regions and is located on the cell surface. It acts with the CD4 protein to support HIV entry ... the G protein-dependent and beta-arrestin-dependent responses that are associated with normal CXCR4 signaling and lead to cell ...
... and at the cell surfaces (eg, as docking complexes and signaling receptors). Consequently, a good understanding of the broader ... Here, we briefly summarize the known catalytic MMP functions and focus on the noncatalytic roles of these proteins, with an ... In addition, many drugs (including in oncology) act by interfering with signaling functions. The present market of successful ... Keywords: MMPs, signaling pathways, PEX domain, noncatalytic function ...
... based on expression of cell surface receptors has been a useful strategy for investigating their development and function ( ... p38 mitogen-activated protein kinase mediates signal integration of TCR/CD28 costimulation in primary murine T cells. J. ... This DP-DP interaction promotes engagement of the signaling lymphocytic activation molecule (SLAM) family receptors SLAMf1 ( ... and CD44 and CD122 fractionated CD24lo iNKT cells into ST1 (CD44loCD122−), ST2 (CD44+CD122−), and ST3 (CD44+CD122+) cells (Fig ...
... cell surface binding protein for MIF.. This work provides the first insight into a membrane receptor for MIF, and the proximate ... and supports those papers that have defined an accessory signaling function for CD74 in immune cell physiology (57, 58, 61). ... The chondroitin sulfate form of invariant chain can enhance stimulation of T cell responses through interaction with CD44. Cell ... Delayed hypersensitivity in vitro: its mediation by cell-free substances formed by lymphoid cell-antigen interaction. Proc. ...
Signal transduction through the beta1 integrin family surface adhesion molecules VLA-4 and VLA-5 of human B-cell precursors ... Binding of FimD on Bordetella pertussis to very late antigen-5 on monocytes activates complement receptor type 3 via protein ... Fibronectin promotes proliferation of naive and memory T cells by signaling through both the VLA-4 and VLA-5 integrin molecules ... Stromal-derived factor-1 in human tumors recruits and alters the function of plasmacytoid precursor dendritic cells. Zou, W., ...
Mouse plasmacytoid cells: long-lived cells, heterogeneous in surface phenotype and function, that differentiate into CD8(+) ... Kupffer cells become activated and express cytokines and signaling molecules. Additionally, activated Kupffer cells display ... contain cargoes such as effector proteins and miRNAs that enable cells to transmit signals. TRAIL, CXCL10, and sphingosine-1- ... while cDC1s present antigens to T cells. After liver injury, DCs gain the capacity to induce hepatic stellate cells, NK cells, ...
The DC-SIGN receptor can modulate TLR signaling by activating the kinase Raf-1 (6,7). The closely related molecule DC-SIGNR (L- ... CD44, has been shown to induce the activation of the NFkB and ERK pathways to promote cell proliferation and survival signals ( ... Background: Protein phosphatase type 2A (PP2A) is an essential protein serine/threonine phosphatase that is conserved in all ... Increased CD74 surface expression has been reported under inflammatory conditions and in certain types of cancer cells implying ...
... are professional antigen-presenting cells that have multiple subpopulations with different phenotypes and immune functions. ... but both cell types expressed high levels of MHC class II and CD44, as well as moderate amounts of CD163, CD204, and Bla36. In ... Finally, mononuclear cells isolated from lung (L-MCs), which are used as precursors for L-DCs, expressed more antigen- ... It is likely that L-DCs play an important role in antigen uptake and processing of respiratory pathogens and are major ...
... inhibitors of glycolysis reduced T cell receptor signaling and recycling to sites of antigen recognition at the cell surface. ... and cell survival through protein-protein interactions (48, 73). In response to glucose and activation signals, HK-II ... Whether other metabolic pathways or molecules regulate signal transduction and modulate T cell functions remains unclear. ... to that of naïve CD44−CD62L+ CD4 T cells (fig. S1, A and B). Whereas naïve CD4 T cells use FAO and OXPHOS for their energy ...
  • Antibody-induced modulation of CD26 on T cells resulted in a concurrent decrease in CD45 expression, enhanced phosphorylation of the TCR-associated zeta chain, and increased p56 Lck src-kinase activity ( 11 ). (pnas.org)
  • This review focuses on the biological properties of immune cell-derived sEVs, including composition and cellular targeting and mechanisms by which these immune cell-derived sEVs influence tumor immunity either by suppressing or promoting tumor growth, are discussed. (frontiersin.org)
  • It has been shown that some viral cellular transformations happen when the virus genome interacts with the DNA of the host cell. (hindawi.com)
  • We have written previously about the Warburg Effect , the observation that cancer cells "bypass normal cellular respiration, that is, glucose converted to pyruvate through glycolysis, and the sequential oxidation of pyruvate through the Krebs Cycle in the mitochondria. (shu.edu)
  • Similar approaches, applied to other model cell systems, will provide valuable new insights into both cellular signal transduction and lipid raft biology. (springer.com)
  • Despite evidence for an extracellular mode of action, no cellular receptor for MIF has been described. (rupress.org)
  • In this review, the authors summarize the role of HA polymers of different molecular weight in tissue regeneration and provide a short overview of main cellular receptors involved in HA signaling. (woundsresearch.com)
  • In the past decade, the field of the cellular microbiology of group A Streptococcus ( S. pyogenes ) infection has made tremendous advances and touched upon several important aspects of pathogenesis, including receptor biology, invasive and evasive phenomena, inflammasome activation, strain-specific autophagic bacterial killing, and virulence factor-mediated programmed cell death. (asmscience.org)
  • Contributes to the normal cleavage of the cellular prion protein (By similarity). (uniprot.org)
  • Trastuzumab and Pertuzumab that target human epidermal growth factor receptor 2 (HER2) have been shown to synergestically inihibit growth of HER2 over-expressing breast cancer cells and also kill them [ 9 ]. (biomedcentral.com)
  • Notable examples are the successful use of hormonal therapy for women with hormone-sensitive tumors ( 5 ), and the use of anti-human epidermal growth factor receptor 2 (HER2) therapy for women with HER2-overexpressing tumors ( 6 ). (aacrjournals.org)
  • Alternative splicing is the basis for the structural and functional diversity of this protein, and may be related to tumor metastasis. (wikipedia.org)
  • Splice variants of CD44 on colon cancer cells display sialofucosylated HCELL glycoforms that serve as P-, L-, and E-selectin ligands and fibrin, but not fibrinogen, receptors under hemodynamic flow conditions pertinent to the process of cancer metastasis. (wikipedia.org)
  • The medical literature contains an increasing number of manuscripts illustrating that the launched concepts and clinical uses of MMP inhibitors against cancer cell invasion and metastasis were too simple and, in fact, wrong. (dovepress.com)
  • CD44, one of important adhesive molecules on cells, is involved in the adhesion and metastasis of tumor cells and plays an important role in tumor development [ 7 - 10 ], but the regulatory mechanism is unclear yet. (biomedcentral.com)
  • Hypoxia inducible factor-1 (HIF-1) is a master regulatory transcription factor controlling multiple cell-autonomous and non-cell-autonomous processes, such as metabolism, angiogenesis, matrix invasion, and cancer metastasis. (biomedsearch.com)
  • Together, our data suggest that the fractalkine network may function as a major contributor to the progression of EOC, and further attention to its role in the metastasis of this deadly malignancy is warranted. (aacrjournals.org)
  • This spreading pattern suggests that the local microenvironment of the peritoneal cavity may contain signals that support homing of the EOC metastasis. (aacrjournals.org)
  • It is possible that ovarian cancer antichemokine receptor antagonists could be useful in preventing metastasis in patients with early-stage disease, as well as in restricting metastatic spread in patients presenting with advanced stages of malignancy. (aacrjournals.org)
  • Colorectal cancer stem cells (CSCs) are responsible for the initiation, progression and metastasis of human colorectal cancers, and have been characterized by the expression of cell surface markers, such as CD44, CD133, CD166 and LGR5. (mdpi.com)
  • The difficulty to cure advanced colorectal cancers is at least partly attributed to the presence of a small population of highly-tumorigenic cancer cells termed cancer stem cells (CSCs) which are responsible for the initiation, progression and metastasis of colorectal cancer [ 2 , 3 , 4 , 5 , 6 ]. (mdpi.com)
  • Concerning Co-029, immunohistofluorescence showed a high expression of Co-029 on epithelial cells in normal colon and a lower expression in tumors, whereas heterogeneity in terms of expression level was observed on metastasis. (mcponline.org)
  • Additionally a decreased expression level of these molecules is correlated with metastasis in these cancers (for a review, see Refs. (mcponline.org)
  • This property of NKT cells, in conjunction with their interactions with antigen-presenting cells, controls downstream innate and adaptive immune responses against cancers and infectious diseases, as well as in several inflammatory disorders. (frontiersin.org)
  • We recently reported that bacteriophage present at sites of bacterial infection are internalized by mammalian cells and that they trigger anti-viral immune responses that antagonize anti-bacterial responses. (stanford.edu)
  • Our finding might help to explain old observations on tolerance induction by B cells, identify the mature immunologic synapse as a central functional module of this process, and suggest the use of naive B-cell-primed regulatory T cells, "bTregs," as a useful approach for therapeutic intervention in adverse adaptive immune responses. (bloodjournal.org)
  • 12 Encounters between DCs and T cells in early and late phases of immune responses, however, last only for several minutes. (bloodjournal.org)
  • Natural killer T (NKT) cells modulate immune responses against pathogens and tumours, as well as immunological tolerance. (embopress.org)
  • T cell immune responses to self-antigens are known to play an important role in the development and progression of RA. (emjreviews.com)
  • To circumvent pathology caused by infectious microbes and tumor growth, the host immune system must constantly clear harmful microorganisms and potentially malignant transformed cells. (hindawi.com)
  • Importantly, the characteristics of the assembled IS will determine the fate of T cells and their capacity to clear malignant cells [ 2 , 7 , 22 - 26 ]. (hindawi.com)
  • Malignant cells that lead to tumor growth and cancer can derive from tissue injury, cell stress, aging, and pathogenic microbes that transform the genetic and physiological properties of normal cells [ 27 ]. (hindawi.com)
  • Importantly, because malignant cells are predisposed to accumulate genetic mutations, these cells will create novel genetic polymorphisms [ 30 ]. (hindawi.com)
  • Thereby, this results into uncontrolled cell growth that occurs with the invasion of surrounding tissues and the spread of malignant cells. (hindawi.com)
  • Experiments in animals have shown that targeting of CD44 by antibodies, antisense oligonucleotides, and CD44-soluble proteins markedly reduces the malignant activities of various neoplasms, stressing the therapeutic potential of anti-CD44 agents. (wikipedia.org)
  • Cancer stem cells (CSCs) are believed to be malignant cells that have the capacity to initiate and maintain tumor growth and survival. (touchoncology.com)
  • Signet ring cell carcinomas are highly malignant dedifferentiated adenocarcinomas. (cancerindex.org)
  • Clinical trials with expanded cord blood for malignant hematological disorders were started and results showed that expanded cell transplantation is feasible and improves neutrophils and platelets engraftment time. (cellr4.org)
  • Malignant EOC cells are shed from the ovarian surface and later attach to the mesothelial layer outlining the peritoneum ( 2 , 7-10 ). (aacrjournals.org)
  • The evolutionary appearance of the vertebrate immune system equipped complex organisms with the ability to resist invasion by pathogenic microbes and to sense and respond to a loss of tissue integrity due to infection, aberrant cell growth, or mechanical injury. (frontiersin.org)
  • Subsequently, numerous new populations of memory T cells were discovered including tissue-resident memory T (Trm) cells, stem memory TSCM cells, and virtual memory T cells. (wikipedia.org)
  • Tissue resident memory T cells (TRM) occupy tissues (skin, lung, etc..) without recirculating. (wikipedia.org)
  • The resulting new blood vessels feed the growing tumors with necessary oxygen and nutrients, allowing the cancer cells to invade nearby tissue, and gain access to immature blood vessels to metastasize throughout the body. (shu.edu)
  • This study demonstrates that the CD14 (show CD14 ELISA Kits )-negative isolation yields an enhanced cell population SFB (show CEBPB ELISA Kits ) that is more potent than MSCP (show SLC25A37 ELISA Kits ) as a cell source for cartilage tissue engineering. (antibodies-online.com)
  • Induction by IL 1 and interferon-gamma: tissue distribution, biochemistry, and function of a natural adherence molecule (ICAM-1). (naver.com)
  • Herein we show that the tissue-specific accumulation of effector T cells can be subverted by a pathogen at the infection site. (biomedsearch.com)
  • VTAs exploit differences between tumor and normal tissue blood vessels, cause the selective and rapid occlusion of tumor vasculature, and lead to massive tumor cell necrosis. (aacrjournals.org)
  • As discussed below, this definition comprises multiple MSC types, including primitive perivascular stem cell-like progenitors-called mesenchymal stem cells by others-as well as further committed connective tissue precursors and fibroblasts. (sciencemag.org)
  • The anatomical distribution and organization of resident MSC populations in different organs are established during development and are driven by unique combinations of local signals, resulting in durable tissue identity. (sciencemag.org)
  • Plastic-adherent multipotent cells, capable of differentiating into bone, cartilage and fat cells (among others), can be isolated from many adult tissue types. (biomedcentral.com)
  • This microenvironment is rich in metabolic intermediates that are released into the extracellular space to shape cell-cell communication and the functional activity of tissue-resident cells. (emjreviews.com)
  • MET signaling regulates intestinal homeostasis and regeneration, as well as adenoma formation. (antibodies-online.com)
  • Because of its high degree of homology with the p56lck inhibitory motif at Y505, I hypothesize that phosphorylation of pcdh18 Y842 by Csk regulates its ability to inhibit p56lck function. (grantome.com)
  • It performs its essential function of regulating systemic blood flow by finely tuning the diameter of blood vessels and regulates vascular tone by releasing vasodilators including nitric oxide and prostaglandin I 2 as well as vasoconstrictors such as endothelin and platelet-activating factor. (biomedcentral.com)
  • The single unifying theme for all memory T cell subtypes is that they are long-lived and can quickly expand to large numbers of effector T cells upon re-exposure to their cognate antigen. (wikipedia.org)
  • Memory T-cell responses have been harder to study, but can also be distinguished from the responses of naive or effector T cells . (nih.gov)
  • Invariant NKT cells (iNKT cells) are a subset of TCRαβ + T cells that recognize glycolipid antigens in the context of the unconventional major histocompatibility complex class I protein CD1D. (rupress.org)
  • Natural killer T (NKT) cells are a subset of innate immune cells that expresses a semi‐invariant TCR recognizing glycolipid antigens presented by the non‐polymorphic MHC class I‐related protein, CD1d ( Matsuda et al , 2008 ). (embopress.org)
  • However, more recent studies have identified NKT‐specific glycolipid antigens derived from microbes and self‐tissues ( Matsuda et al , 2008 ). (embopress.org)
  • CD44 monoclonal antibody from Santa Cruz Co. and Wuhan Boster Co. (biomedcentral.com)
  • The later samples were stained with a primary monoclonal antibody against CD44 (Rat anti-CD44s monoclonal) and a secondary rabbit, anti-rat antibody (Biotinylated Rabbit anti-Rat). (auburn.edu)
  • Samples fixed with glutaraldehyde/formalin were stained with the primary antibody Rat anti-CD44s monoclonal and gold conjugated protein A. These samples were evaluated using a transmission electron microscope for localization of gold particles. (auburn.edu)
  • These memory T cells lack lymph node-homing receptors and are thus found in the peripheral circulation and tissues. (wikipedia.org)
  • More recent studies suggested that DCs derived from tissues without "danger" signal stimulation should be regarded as immature DCs, based on their major role in antigen uptake and endocytosis of antigens [ 11 , 14 ]. (biomedcentral.com)
  • Cells of the innate immune system patrol our organs and tissues in an effort to identify and eliminate threats with a quick but general response, which is similar for many different pathogens. (elifesciences.org)
  • Results observed with cell lines were validated by screening a cohort of primary human breast normal and tumor tissues using immunofluorescence. (biomedcentral.com)
  • In primary breast tumor tissues, HCAb2 showed positive binding to both E-cadherin positive and negative tumor cells. (biomedcentral.com)
  • Pcdh18 is a cell surface adhesion molecule expressed in various tissues, however, in the hematopoietic system, is expressed only in memory CD8+ T cells. (grantome.com)
  • Therefore, a central question is whether naive T cells could access tumor masses in nonlymphoid tissues. (pubmedcentralcanada.ca)
  • The notion that fibrosis in multiple tissues is driven by virtually identical MSC populations and a common set of signals is rapidly becoming obsolete. (sciencemag.org)
  • Those waves comprise mesenchymal progenitor cells (MPCs) from at least two different sources, namely, the neuroectoderm and the primitive streak (via the mesoderm), which contribute to the generation of connective tissues throughout the body ( 1 , 2 ). (sciencemag.org)
  • Despite phenotypic similarities, derivatives from those progenitor cell populations present in adult tissues have unique epigenetic properties and retain lineage-specific capabilities ( 3 - 5 ). (sciencemag.org)
  • Further evidence supporting the unique anatomical identity of fibrogenic stromal cells comes from a recent systematic study of phenotypically similar perivascular MSC populations residing in multiple adult human tissues. (sciencemag.org)
  • Because those cells share the common marker signature CD146 + CD45 − CD34 − and were previously found to generate multiple connective tissues in vitro, it was assumed that they constituted one ubiquitous population of adult mesenchymal progenitor/stem cells ( 6 ). (sciencemag.org)
  • Positive immunolabelling for CD44 was found in all the tissues evaluated. (auburn.edu)
  • 9 During preclinical RA, when autoreactive T cells expand and immunological tolerance is broken, the main sites of disease are the secondary lymphoid tissues. (emjreviews.com)
  • Signature of Author Date of Graduation iv THESIS ABSTRACT THE PRESENCE OF THE HYALURONAN RECEPTOR CD44 IN THE REPRODUCTIVE TRACT OF THE MARE Isabel Rodriguez Hurtado Master of Sciences, December 17, 2007 (LMV, Universidad Complutense de Madrid, 2001) 61 Typed Pages Directed by Allison Stewart Objective - To investigate the presence and localization of the hyaluronan receptor CD44 in the reproductive tract of the mare. (auburn.edu)
  • Systemic immune response is intact in cancer patients and animal models, however, TIL have no lytic function in situ (or in vitro) thus demonstrating tumor-induced immune suppression that is likely to underlie tumor escape from elimination by antitumor immune response. (grantome.com)
  • EFNB1 is known to be able to co-stimulate T cells in vitro and to modulate thymocyte development in a model of foetal thymus organ culture. (biomedcentral.com)
  • Furthermore, our system provides a basis for further development of iPSC-derived cell products with the potential for various clinical applications, including infusions of in vitro derived autologous T-cells to stabilize patients after hematopoietic stem cell transplantation. (prolekare.cz)
  • In vitro disease modeling with induced pluripotent stem cells (iPSCs) provides a practical alternative, and the study of several disorders has benefitted enormously from the convergence of three key technologies: modern genomics that links genetic variants to disease phenotypes, the ability to generate patient-specific iPSCs that can be differentiated into cell types affected by disease, and powerful tools for editing complex genomes [ 1 , 2 ]. (prolekare.cz)
  • Nevertheless, studies by other laboratories and our own have shown that, although many costimulatory molecule blockers effectively prevent disease when administered before disease onset, they are less effective after disease onset. (arvojournals.org)
  • However, at this point, the phenotype and function of DC from different sources is not well understood for many veterinary species including horses, and most studies use B-DCs for investigating veterinary diseases. (biomedcentral.com)
  • pERK1 /2 is a regulator of CD44 expression, and increased CD44 expression leads to a pro-sclerotic and migratory parietal epithelial cell phenotype in focal segmental glomerulosclerosis. (antibodies-online.com)
  • These results demonstrate a novel positive-feedback loop that links the myofibroblast phenotype to TGFbeta1 (show TGFB1 ELISA Kits )-stimulated CD44V6/ ERK (show EPHB2 ELISA Kits )/ EGR1 (show EGR1 ELISA Kits ) signaling. (antibodies-online.com)
  • Utilizing site-directed mutagenesis, I have shown that Y842 is required for the pcdh18 inhibitory phenotype in transfected T cells. (grantome.com)
  • T cells can differentiate toward the T helper (Th) 1 or Th17 lineages, imposing a hyper-inflammatory phenotype. (emjreviews.com)
  • Administration of Ag in the absence of adjuvant results in some clonal expansion of CD4 + T cells in draining lymph nodes, but the cells are rendered tolerant to subsequent challenge with Ag. (jimmunol.org)
  • Our strategy involved identification of activated and proliferating B-cells in sentinel lymph nodes of breast cancer patients. (biomedcentral.com)
  • Studies of T cell responses to tumors have focused on the draining lymph node (LN) as the site of activation. (pubmedcentralcanada.ca)
  • 9 Lymph node physiology and CD44? (auburn.edu)