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.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.Antigens, CD137: A member of the tumor necrosis factor receptor superfamily that is specific for 4-1BB LIGAND. It is found in a variety of immune cell types including activated T-LYMPHOCYTES; NATURAL KILLER CELLS; and DENDRITIC CELLS. Activation of the receptor on T-LYMPHOCYTES plays a role in their expansion, production of cytokines and survival. Signaling by the activated receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.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.Inducible T-Cell Co-Stimulator Protein: A costimulatory receptor that is specific for INDUCIBLE T-CELL CO-STIMULATOR LIGAND. The receptor is associated with a diverse array of immunologically-related effects including the increased synthesis of INTERLEUKIN 10 in REGULATORY T-LYMPHOCYTES and the induction of PERIPHERAL TOLERANCE.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.Receptors, OX40: A tumor necrosis family receptor with specificity for OX40 LIGAND. It is found on the surface of activated T-LYMPHOCYTES where it plays a role in enhancing cytokine production and proliferation of CD4-POSITIVE T-LYMPHOCYTES. Signaling by the activated receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.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, 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.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.Antigens: Substances that are recognized by the immune system and induce an immune reaction.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).4-1BB Ligand: A membrane bound member of the TNF superfamily that is expressed on activated B-LYMPHOCYTES; MACROPHAGES; and DENDRITIC CELLS. The ligand is specific for the 4-1BB RECEPTOR and may play a role in inducing the proliferation of activated peripheral blood T-LYMPHOCYTES.CTLA-4 Antigen: An inhibitory T CELL receptor that is closely related to CD28 ANTIGEN. It has specificity for CD80 ANTIGEN and CD86 ANTIGEN and acts as a negative regulator of peripheral T cell function. CTLA-4 antigen is believed to play role in inducing PERIPHERAL TOLERANCE.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.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.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.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.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.Receptors, AMPA: A class of ionotropic glutamate receptors characterized by their affinity for the agonist AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid).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.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.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.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.Immunoconjugates: Combinations of diagnostic or therapeutic substances linked with specific immune substances such as IMMUNOGLOBULINS; MONOCLONAL ANTIBODIES; or ANTIGENS. Often the diagnostic or therapeutic substance is a radionuclide. These conjugates are useful tools for specific targeting of DRUGS and RADIOISOTOPES in the CHEMOTHERAPY and RADIOIMMUNOTHERAPY of certain cancers.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.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.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Antigens, CD70: A transmembrane protein belonging to the tumor necrosis factor superfamily that specifically binds to CD27 ANTIGEN. It is found on activated T-LYMPHOCYTES; B-LYMPHOCYTES; and DENDRITIC CELLS where it plays a role in stimulating the proliferation of CD4-POSITIVE T-LYMPHOCYTES and CD8-POSITIVE T-LYMPHOCYTES.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.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.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.Antigens, Bacterial: Substances elaborated by bacteria that have antigenic activity.Mice, Inbred C57BLAmino 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.Interleukin-2: A soluble substance elaborated by antigen- or mitogen-stimulated T-LYMPHOCYTES which induces DNA synthesis in naive lymphocytes.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)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.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.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.Antigens, CD27: A member of the tumor necrosis factor receptor superfamily found on most T-LYMPHOCYTES. Activation of the receptor by CD70 ANTIGEN results in the increased proliferation of CD4-POSITIVE T-LYMPHOCYTES and CD8-POSITIVE T-LYMPHOCYTES. Signaling by the activated receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.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.Antigens, CD19: Differentiation antigens expressed on B-lymphocytes and B-cell precursors. They are involved in regulation of B-cell proliferation.Programmed Cell Death 1 Receptor: An inhibitory T-lymphocyte receptor that has specificity for CD274 ANTIGEN and PROGRAMMED CELL DEATH 1 LIGAND 2 PROTEIN. Signaling by the receptor limits T cell proliferation and INTERFERON GAMMA synthesis. The receptor also may play an essential role in the regulatory pathway that induces PERIPHERAL TOLERANCE.Mice, Inbred BALB CReceptors, N-Methyl-D-Aspartate: A class of ionotropic glutamate receptors characterized by affinity for N-methyl-D-aspartate. NMDA receptors have an allosteric binding site for glycine which must be occupied for the channel to open efficiently and a site within the channel itself to which magnesium ions bind in a voltage-dependent manner. The positive voltage dependence of channel conductance and the high permeability of the conducting channel to calcium ions (as well as to monovalent cations) are important in excitotoxicity and neuronal plasticity.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.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)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.Receptors, Natural Killer Cell: Receptors that are specifically found on the surface of NATURAL KILLER CELLS. They play an important role in regulating the cellular component of INNATE IMMUNITY.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.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.Antigens, Viral: Substances elaborated by viruses that have antigenic activity.Cell Line: Established cell cultures that have the potential to propagate indefinitely.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.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.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.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.Mice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.Hippocampus: A curved elevation of GRAY MATTER extending the entire length of the floor of the TEMPORAL HORN of the LATERAL VENTRICLE (see also TEMPORAL LOBE). The hippocampus proper, subiculum, and DENTATE GYRUS constitute the hippocampal formation. Sometimes authors include the ENTORHINAL CORTEX in the hippocampal formation.Receptors, Tumor Necrosis Factor: Cell surface receptors that bind TUMOR NECROSIS FACTORS and trigger changes which influence the behavior of cells.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, 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.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)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).Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.NK Cell Lectin-Like Receptor Subfamily K: An activating NK cell lectin-like receptor subfamily that regulates immune responses to INFECTION and NEOPLASMS. Members of this subfamily generally occur as homodimers.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.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.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.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.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.Receptors, Nerve Growth Factor: Cell surface receptors that bind NERVE GROWTH FACTOR; (NGF) and a NGF-related family of neurotrophic factors that includes neurotrophins, BRAIN-DERIVED NEUROTROPHIC FACTOR and CILIARY NEUROTROPHIC FACTOR.Antigens, CD58: Glycoproteins with a wide distribution on hematopoietic and non-hematopoietic cells and strongly expressed on macrophages. CD58 mediates cell adhesion by binding to CD2; (ANTIGENS, CD2); and this enhances antigen-specific T-cell activation.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.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.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.ADP-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.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.Antigen-Presenting Cells: A heterogeneous group of immunocompetent cells that mediate the cellular immune response by processing and presenting antigens to the T-cells. Traditional antigen-presenting cells include MACROPHAGES; DENDRITIC CELLS; LANGERHANS CELLS; and B-LYMPHOCYTES. FOLLICULAR DENDRITIC CELLS are not traditional antigen-presenting cells, but because they hold antigen on their cell surface in the form of IMMUNE COMPLEXES for B-cell recognition they are considered so by some authors.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.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.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.Antigens, Differentiation, B-Lymphocyte: Membrane antigens associated with maturation stages of B-lymphocytes, often expressed in tumors of B-cell origin.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.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.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.Antigens, Protozoan: Any part or derivative of any protozoan that elicits immunity; malaria (Plasmodium) and trypanosome antigens are presently the most frequently encountered.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, Polyomavirus Transforming: Polyomavirus antigens which cause infection and cellular transformation. The large T antigen is necessary for the initiation of viral DNA synthesis, repression of transcription of the early region and is responsible in conjunction with the middle T antigen for the transformation of primary cells. Small T antigen is necessary for the completion of the productive infection cycle.Inducible T-Cell Co-Stimulator Ligand: A B7 antigen that binds specifically to INDUCIBLE T-CELL CO-STIMULATOR PROTEIN on T-CELLS. It provides a costimulatory signal for T-cell proliferation and cytokine secretion.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.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.Epitopes: Sites on an antigen that interact with specific antibodies.H-2 Antigens: The major group of transplantation antigens in the mouse.Carcinoembryonic Antigen: A glycoprotein that is secreted into the luminal surface of the epithelia in the gastrointestinal tract. It is found in the feces and pancreaticobiliary secretions and is used to monitor the response to colon cancer treatment.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.NAD+ NucleosidaseAntigens, Fungal: Substances of fungal origin that have antigenic activity.B7 Antigens: A family of cell-surface proteins found on ANTIGEN-PRESENTING CELLS. B7 antigens are ligands for specific cell surface receptor subtypes found on T-CELLS. They play an immunomodulatory role by stimulating or inhibiting the T-CELL activation process.Antigens, CD30: A member of the tumor necrosis factor receptor superfamily that may play a role in the regulation of NF-KAPPA B and APOPTOSIS. They are found on activated T-LYMPHOCYTES; B-LYMPHOCYTES; NEUTROPHILS; EOSINOPHILS; MAST CELLS and NK CELLS. Overexpression of CD30 antigen in hematopoietic malignancies make the antigen clinically useful as a biological tumor marker. Signaling of the receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.Antigens, CD18: Cell-surface glycoprotein beta-chains that are non-covalently linked to specific alpha-chains of the CD11 family of leukocyte-adhesion molecules (RECEPTORS, LEUKOCYTE-ADHESION). A defect in the gene encoding CD18 causes LEUKOCYTE-ADHESION DEFICIENCY SYNDROME.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.Sialic Acid Binding Ig-like Lectin 3: A 67-kDa sialic acid binding lectin that is specific for MYELOID CELLS and MONOCYTE-MACROPHAGE PRECURSOR CELLS. This protein is the smallest siglec subtype and contains a single immunoglobulin C2-set domain. It may play a role in intracellular signaling via its interaction with SHP-1 PROTEIN-TYROSINE PHOSPHATASE and SHP-2 PROTEIN-TYROSINE PHOSPHATASE.Antigens, Helminth: Any part or derivative of a helminth that elicits an immune reaction. The most commonly seen helminth antigens are those of the schistosomes.Receptors, Antigen, B-Cell: IMMUNOGLOBULINS on the surface of B-LYMPHOCYTES. Their MESSENGER RNA contains an EXON with a membrane spanning sequence, producing immunoglobulins in the form of type I transmembrane proteins as opposed to secreted immunoglobulins (ANTIBODIES) which do not contain the membrane spanning segment.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Interferon-gamma: The major interferon produced by mitogenically or antigenically stimulated LYMPHOCYTES. It is structurally different from TYPE I INTERFERON and its major activity is immunoregulation. It has been implicated in the expression of CLASS II HISTOCOMPATIBILITY ANTIGENS in cells that do not normally produce them, leading to AUTOIMMUNE DISEASES.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.Antigens, CD274: An inhibitory B7 antigen that has specificity for the T-CELL receptor PROGRAMMED CELL DEATH 1 PROTEIN. CD274 antigen provides negative signals that control and inhibit T-cell responses and is found at higher than normal levels on tumor cells, suggesting its potential role in TUMOR IMMUNE EVASION.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.Antigens, CD43: A sialic acid-rich protein and an integral cell membrane mucin. It plays an important role in activation of T-LYMPHOCYTES.Antigens, CD11c: An integrin alpha subunit of approximately 150-kDa molecular weight. It is expressed at high levels on monocytes and combines with CD18 ANTIGEN to form the cell surface receptor INTEGRIN ALPHAXBETA2. The subunit contains a conserved I-domain which is characteristic of several of alpha integrins.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.Spleen: An encapsulated lymphatic organ through which venous blood filters.Immune Tolerance: The specific failure of a normally responsive individual to make an immune response to a known antigen. It results from previous contact with the antigen by an immunologically immature individual (fetus or neonate) or by an adult exposed to extreme high-dose or low-dose antigen, or by exposure to radiation, antimetabolites, antilymphocytic serum, etc.Cell SeparationImmunologic Memory: The altered state of immunologic responsiveness resulting from initial contact with antigen, which enables the individual to produce antibodies more rapidly and in greater quantity in response to secondary antigenic stimulus.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.Immunoglobulin G: The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.T-Lymphocytes, Cytotoxic: Immunized T-lymphocytes which can directly destroy appropriate target cells. These cytotoxic lymphocytes may be generated in vitro in mixed lymphocyte cultures (MLC), in vivo during a graft-versus-host (GVH) reaction, or after immunization with an allograft, tumor cell or virally transformed or chemically modified target cell. The lytic phenomenon is sometimes referred to as cell-mediated lympholysis (CML). These CD8-positive cells are distinct from NATURAL KILLER CELLS and NATURAL KILLER T-CELLS. There are two effector phenotypes: TC1 and TC2.Antigen Presentation: The process by which antigen is presented to lymphocytes in a form they can recognize. This is performed by antigen presenting cells (APCs). Some antigens require processing before they can be recognized. Antigen processing consists of ingestion and partial digestion of the antigen by the APC, followed by presentation of fragments on the cell surface. (From Rosen et al., Dictionary of Immunology, 1989)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.Antigens, CD15: A trisaccharide antigen expressed on glycolipids and many cell-surface glycoproteins. In the blood the antigen is found on the surface of NEUTROPHILS; EOSINOPHILS; and MONOCYTES. In addition, CD15 antigen is a stage-specific embryonic antigen.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.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.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.Receptors, Interleukin-2: Receptors present on activated T-LYMPHOCYTES and B-LYMPHOCYTES that are specific for INTERLEUKIN-2 and play an important role in LYMPHOCYTE ACTIVATION. They are heterotrimeric proteins consisting of the INTERLEUKIN-2 RECEPTOR ALPHA SUBUNIT, the INTERLEUKIN-2 RECEPTOR BETA SUBUNIT, and the INTERLEUKIN RECEPTOR COMMON GAMMA-CHAIN.Adjuvants, Immunologic: Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (Freund's adjuvant, BCG, Corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity.Antigens, Viral, Tumor: Those proteins recognized by antibodies from serum of animals bearing tumors induced by viruses; these proteins are presumably coded for by the nucleic acids of the same viruses that caused the neoplastic transformation.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Antigens, CD47: A ubiquitously expressed membrane glycoprotein. It interacts with a variety of INTEGRINS and mediates responses to EXTRACELLULAR MATRIX PROTEINS.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.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.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, CD11: A group of three different alpha chains (CD11a, CD11b, CD11c) that are associated with an invariant CD18 beta chain (ANTIGENS, CD18). The three resulting leukocyte-adhesion molecules (RECEPTORS, LEUKOCYTE ADHESION) are LYMPHOCYTE FUNCTION-ASSOCIATED ANTIGEN-1; MACROPHAGE-1 ANTIGEN; and ANTIGEN, P150,95.T-Lymphocyte Subsets: A classification of T-lymphocytes, especially into helper/inducer, suppressor/effector, and cytotoxic subsets, based on structurally or functionally different populations of cells.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, CD11b: A CD antigen that contains a conserved I domain which is involved in ligand binding. When combined with CD18 the two subunits form MACROPHAGE-1 ANTIGEN.Antigens, CD46: A ubiquitously expressed complement receptor that binds COMPLEMENT C3B and COMPLEMENT C4B and serves as a cofactor for their inactivation. CD46 also interacts with a wide variety of pathogens and mediates immune response.Antigens, CD59: Small glycoproteins found on both hematopoietic and non-hematopoietic cells. CD59 restricts the cytolytic activity of homologous complement by binding to C8 and C9 and blocking the assembly of the membrane attack complex. (From Barclay et al., The Leukocyte Antigen FactsBook, 1993, p234)Th1 Cells: Subset of helper-inducer T-lymphocytes which synthesize and secrete interleukin-2, gamma-interferon, and interleukin-12. Due to their ability to kill antigen-presenting cells and their lymphokine-mediated effector activity, Th1 cells are associated with vigorous delayed-type hypersensitivity reactions.Hematopoietic Stem Cells: Progenitor cells from which all blood cells derive.Antibodies, Blocking: Antibodies that inhibit the reaction between ANTIGEN and other antibodies or sensitized T-LYMPHOCYTES (e.g., antibodies of the IMMUNOGLOBULIN G class that compete with IGE antibodies for antigen, thereby blocking an allergic response). Blocking antibodies that bind tumors and prevent destruction of tumor cells by CYTOTOXIC T-LYMPHOCYTES have also been called enhancing antibodies. (Rosen et al., Dictionary of Immunology, 1989)Ovalbumin: An albumin obtained from the white of eggs. It is a member of the serpin superfamily.Proliferating Cell Nuclear Antigen: Nuclear antigen with a role in DNA synthesis, DNA repair, and cell cycle progression. PCNA is required for the coordinated synthesis of both leading and lagging strands at the replication fork during DNA replication. PCNA expression correlates with the proliferation activity of several malignant and non-malignant cell types.HLA-A2 Antigen: A specific HLA-A surface antigen subtype. Members of this subtype contain alpha chains that are encoded by the HLA-A*02 allele family.T-Lymphocytes, Regulatory: CD4-positive T cells that inhibit immunopathology or autoimmune disease in vivo. They inhibit the immune response by influencing the activity of other cell types. Regulatory T-cells include naturally occurring CD4+CD25+ cells, IL-10 secreting Tr1 cells, and Th3 cells.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).Costimulatory and Inhibitory T-Cell Receptors: A family of receptors that modulate the activation of T-LYMPHOCYTES by the T-CELL ANTIGEN RECEPTOR. The receptors are responsive to one or more B7 ANTIGENS found on ANTIGEN-PRESENTING CELLS and, depending upon the specific ligand-receptor combination, modulate a variety of T-cell functions such as the rate of clonal expansion, CELL SURVIVAL and cytokine production. Although commonly referred to as costimulatory receptors, some of the receptors have inhibitory effects such as inducing PERIPHERAL TOLERANCE.Antigens, CD57: Oligosaccharide antigenic determinants found principally on NK cells and T-cells. Their role in the immune response is poorly understood.Coculture Techniques: A technique of culturing mixed cell types in vitro to allow their synergistic or antagonistic interactions, such as on CELL DIFFERENTIATION or APOPTOSIS. Coculture can be of different types of cells, tissues, or organs from normal or disease states.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Up-Regulation: A positive regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.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.Programmed Cell Death 1 Ligand 2 Protein: A costimulatory B7 antigen that has specificity for the T-CELL receptor PROGRAMMED CELL DEATH 1 RECEPTOR. It is closely-related to CD274 antigen; however, its expression is restricted to DENDRITIC CELLS and activated MACROPHAGES.Isoantigens: Antigens that exist in alternative (allelic) forms in a single species. When an isoantigen is encountered by species members who lack it, an immune response is induced. Typical isoantigens are the BLOOD GROUP ANTIGENS.Prostate-Specific Antigen: A glycoprotein that is a kallikrein-like serine proteinase and an esterase, produced by epithelial cells of both normal and malignant prostate tissue. It is an important marker for the diagnosis of prostate cancer.Antigens, CD81: Tetraspanin proteins that are involved in a variety of cellular functions including BASEMENT MEMBRANE assembly, and in the formation of a molecular complexes on the surface of LYMPHOCYTES.O Antigens: The lipopolysaccharide-protein somatic antigens, usually from gram-negative bacteria, important in the serological classification of enteric bacilli. The O-specific chains determine the specificity of the O antigens of a given serotype. O antigens are the immunodominant part of the lipopolysaccharide molecule in the intact bacterial cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)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.Antibody Formation: The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.Bone Marrow Cells: Cells contained in the bone marrow including fat cells (see ADIPOCYTES); STROMAL CELLS; MEGAKARYOCYTES; and the immediate precursors of most blood cells.Interleukin-12: A heterodimeric cytokine that plays a role in innate and adaptive immune responses. Interleukin-12 is a 70 kDa protein that is composed of covalently linked 40 kDa and 35 kDa subunits. It is produced by DENDRITIC CELLS; MACROPHAGES and a variety of other immune cells and plays a role in the stimulation of INTERFERON-GAMMA production by T-LYMPHOCYTES and NATURAL KILLER CELLS.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)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.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.Th2 Cells: Subset of helper-inducer T-lymphocytes which synthesize and secrete the interleukins IL-4, IL-5, IL-6, and IL-10. These cytokines influence B-cell development and antibody production as well as augmenting humoral responses.Antigens, CD31: Cell adhesion molecules present on virtually all monocytes, platelets, and granulocytes. CD31 is highly expressed on endothelial cells and concentrated at the junctions between them.Cancer Vaccines: Vaccines or candidate vaccines designed to prevent or treat cancer. Vaccines are produced using the patient's own whole tumor cells as the source of antigens, or using tumor-specific antigens, often recombinantly produced.Immunization: Deliberate stimulation of the host's immune response. ACTIVE IMMUNIZATION involves administration of ANTIGENS or IMMUNOLOGIC ADJUVANTS. PASSIVE IMMUNIZATION involves administration of IMMUNE SERA or LYMPHOCYTES or their extracts (e.g., transfer factor, immune RNA) or transplantation of immunocompetent cell producing tissue (thymus or bone marrow).Mice, SCID: Mice homozygous for the mutant autosomal recessive gene "scid" which is located on the centromeric end of chromosome 16. These mice lack mature, functional lymphocytes and are thus highly susceptible to lethal opportunistic infections if not chronically treated with antibiotics. The lack of B- and T-cell immunity resembles severe combined immunodeficiency (SCID) syndrome in human infants. SCID mice are useful as animal models since they are receptive to implantation of a human immune system producing SCID-human (SCID-hu) hematochimeric mice.Cell Line, Tumor: A cell line derived from cultured tumor cells.CD4 Lymphocyte Count: The number of CD4-POSITIVE T-LYMPHOCYTES per unit volume of BLOOD. Determination requires the use of a fluorescence-activated flow cytometer.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.Epitopes, T-Lymphocyte: Antigenic determinants recognized and bound by the T-cell receptor. Epitopes recognized by the T-cell receptor are often located in the inner, unexposed side of the antigen, and become accessible to the T-cell receptors after proteolytic processing of the antigen.Interleukin-4: A soluble factor produced by activated T-LYMPHOCYTES that induces the expression of MHC CLASS II GENES and FC RECEPTORS on B-LYMPHOCYTES and causes their proliferation and differentiation. It also acts on T-lymphocytes, MAST CELLS, and several other hematopoietic lineage cells.Kinetics: The rate dynamics in chemical or physical systems.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.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.Immunity, Cellular: Manifestations of the immune response which are mediated by antigen-sensitized T-lymphocytes via lymphokines or direct cytotoxicity. This takes place in the absence of circulating antibody or where antibody plays a subordinate role.Antigens, Tumor-Associated, Carbohydrate: Carbohydrate antigens expressed by malignant tissue. They are useful as tumor markers and are measured in the serum by means of a radioimmunoassay employing monoclonal antibodies.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.Antigens, CD55: GPI-linked membrane proteins broadly distributed among hematopoietic and non-hematopoietic cells. CD55 prevents the assembly of C3 CONVERTASE or accelerates the disassembly of preformed convertase, thus blocking the formation of the membrane attack complex.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.Lymph Nodes: They are oval or bean shaped bodies (1 - 30 mm in diameter) located along the lymphatic system.CD30 Ligand: A membrane-bound tumor necrosis family member found primarily on activated T-LYMPHOCYTES that binds specifically to CD30 ANTIGEN. It may play a role in INFLAMMATION and immune regulation.Adoptive Transfer: Form of passive immunization where previously sensitized immunologic agents (cells or serum) are transferred to non-immune recipients. When transfer of cells is used as a therapy for the treatment of neoplasms, it is called adoptive immunotherapy (IMMUNOTHERAPY, ADOPTIVE).Endocytosis: Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.HLA-D Antigens: Human immune-response or Class II antigens found mainly, but not exclusively, on B-lymphocytes and produced from genes of the HLA-D locus. They are extremely polymorphic families of glycopeptides, each consisting of two chains, alpha and beta. This group of antigens includes the -DR, -DQ and -DP designations, of which HLA-DR is most studied; some of these glycoproteins are associated with certain diseases, possibly of immune etiology.Mice, Inbred Strains: Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.Cell Communication: Any of several ways in which living cells of an organism communicate with one another, whether by direct contact between cells or by means of chemical signals carried by neurotransmitter substances, hormones, and cyclic AMP.Receptors, Antigen: Molecules on the surface of B- and T-lymphocytes that recognize and combine with specific antigens.Mice, Inbred C3HOX40 Ligand: A membrane-bound tumor necrosis family member that is expressed on activated antigen-presenting cells such as B-LYMPHOCYTES and MACROPHAGES. It signals T-LYMPHOCYTES by binding the OX40 RECEPTOR.Immunoglobulins: Multi-subunit proteins which function in IMMUNITY. They are produced by B LYMPHOCYTES from the IMMUNOGLOBULIN GENES. They are comprised of two heavy (IMMUNOGLOBULIN HEAVY CHAINS) and two light chains (IMMUNOGLOBULIN LIGHT CHAINS) with additional ancillary polypeptide chains depending on their isoforms. The variety of isoforms include monomeric or polymeric forms, and transmembrane forms (B-CELL ANTIGEN RECEPTORS) or secreted forms (ANTIBODIES). They are divided by the amino acid sequence of their heavy chains into five classes (IMMUNOGLOBULIN A; IMMUNOGLOBULIN D; IMMUNOGLOBULIN E; IMMUNOGLOBULIN G; IMMUNOGLOBULIN M) and various subclasses.
... cells typically express a large number of self derived pMHC on their cell surface and although the T cell antigen receptor can ... The only co-stimulatory receptor expressed constitutively by naïve T cells is CD28, so co-stimulation for these cells comes ... from the CD80 and CD86 proteins, which together constitute the B7 protein, (B7.1 and B7.2, respectively) on the APC. Other ... These self-antigens are expressed by thymic cortical epithelial cells on MHC molecules on the surface of cortical epithelial ...
The B7 (B7-1/B7-2) protein is present on the APC surface, and it interacts with the CD28 receptor on the T cell surface. This ... surface protein on a T cell, can produce a costimulatory signal or a coinhibitory signal to enhance or decrease the activity of ... There are two major types of B7 proteins: B7-1 or CD80, and B7-2 or CD86. However, it is not known if they differ significantly ... This is also called "Signal 1" and its main purpose is to guarantee antigen specificity of the T cell activation. However, MHC ...
Simultaneously, they upregulate cell-surface receptors that act as co-receptors in T-cell activation such as CD80 (B7.1), CD86 ... alongside non-antigen specific costimulatory signals. Dendritic cells can also induce T-cell tolerance (unresponsiveness). ... Their main function is to process antigen material and present it on the cell surface to the T cells of the immune system. They ... Distinct surface antigens that characterize dendritic cells have only become known from 2000 on; before that, researchers had ...
It acts as an "off" switch when bound to CD80 or CD86 on the surface of antigen-presenting cells. The CTLA-4 protein is encoded ... "Both extracellular immunoglobin-like domains of CD80 contain residues critical for binding T cell surface receptors CTLA-4 and ... CTLA4 is homologous to the T-cell co-stimulatory protein, CD28, and both molecules bind to CD80 and CD86, also called B7-1 and ... CTLA-4 binds CD80 and CD86 with greater affinity and avidity than CD28 thus enabling it to outcompete CD28 for its ligands. ...
... which is on the surface of all naïve CD4+ and CD8+ T-lymphocytes, can bind ligands CD80 and CD86). Receptor-ligand engagement ... 229(1):271-93 Jenkins MK, Taylor PS, Norton SD, Urdahl KB (1991), CD28 delivers a costimulatory signal involved in antigen- ... T-lymphocytes must receive costimulatory signal. There are costimulatory molecules on T-cell surface and APCs express their ... for instance CD152/CTLA-4 receptor which binds CD80 and CD86 as well). If T-lymphocyte does not receive costimulatory signal, ...
... this is done by co-stimulatory molecules such as the proteins CD80 (B7.1) or CD86 (B7.2), although other additional co- ... The peptide-loaded MHC engages with the cognate T cell receptor (TCR) found on the T cells. T cells need another signal to ... that there is something foreign in the body with specific cell surface molecules. aAPCs are synthetic versions of these ... As specific cancer antigens have been discovered, these antigens can be loaded to aAPCs to successfully stimulate and expand ...
... which interacts with CD80 (B7.1) and CD86 (B7.2) on the membrane of APC. Another costimulatory receptor expressed by T cells is ... Co-stimulation is required in addition to the antigen-specific signal from their antigen receptors. T cells require two signals ... which continue to bind to microbal surface, B cells express complement receptor CR2 (CD21) to bind to iC3b, C3dg, or C3d. This ... the co-stimulatory signal, is antigen nonspecific and is provided by the interaction between co-stimulatory molecules expressed ...
B7H4 belongs to the B7 family (see CD80; MIM 112203) of costimulatory proteins. These proteins are expressed on the surface of ... "BTLA is a lymphocyte inhibitory receptor with similarities to CTLA-4 and PD-1". Nature Immunology. 4 (7): 670-9. doi:10.1038/ ... antigen-presenting cells and interact with ligands (e.g., CD28; MIM 186760) on T lymphocytes.[supplied by OMIM] B7-H4 is an ... Chen Y, Yang C, Xie Z, Zou L, Ruan Z, Zhang X, Tang Y, Fei L, Jia Z, Wu Y (December 2006). "Expression of the novel co-stimulatory ...
"Both extracellular immunoglobin-like domains of CD80 contain residues critical for binding T cell surface receptors CTLA-4 and ... and T cell costimulatory activity of the murine homologue of the human B lymphocyte activation antigen B7". The Journal of ... "Both extracellular immunoglobin-like domains of CD80 contain residues critical for binding T cell surface receptors CTLA-4 and ... Reeves RH, Patch D, Sharpe AH, Borriello F, Freeman GJ, Edelhoff S, Disteche C (August 1997). "The costimulatory genes Cd80 and ...
... co-stimulatory molecules (CD80, CD86) and adhesion receptors (CD11a, CD18, CD54). Thus activated Vγ9Vδ2 T cells behave like ... Gamma delta T cells (γδ T cells) are T cells that have a distinctive T-cell receptor (TCR) on their surface. Most T cells are ... The antigens recognized by non-Vδ2 T cells expanded in the above infectious contexts have not been characterized, but the fact ... It is still not clear whether these non-peptidic antigens bind directly to the Vγ9/Vδ2 TCR or if a presenting element exists. ...
... cells typically express a large number of self derived pMHC on their cell surface and although the T cell antigen receptor can ... The only co-stimulatory receptor expressed constitutively by naïve T cells is CD28, so co-stimulation for these cells comes ... from the CD80 and CD86 proteins, which together constitute the B7 protein, (B7.1 and B7.2, respectively) on the APC. Other ... A T cell becomes a CD4+ cell by down-regulating expression of its CD8 cell surface receptors. If the cell does not lose its ...
... bring that complex to its surface, and present it to the T cell receptor on the surface of the T cell. For signal 2, the APC ... Abatacept prevents antigen-presenting cells (APCs) from delivering the co-stimulatory signal. This prevents the T cells from ... One of those signals is the major histocompatibility complex (MHC), combined with the antigen, and the other signal is the CD80 ... In order for T cells to be activated and attack an antigen, that antigen must be presented to the T cell by an antigen- ...
Both CD80 and CD86 activate the CD28 receptor. These proteins are also known as co-stimulatory molecules. Although the ... antigens to their surface, such as follicular dendritic cells, but unprocessed antigens do not interact with T cells and are ... The T cell receptor (TCR) consists of both constant and variable regions. The variable region determines what antigen the T ... It has been proposed that the larger CD45RA+ may decrease the accessibility of the T cell receptor for the antigen-MHC molecule ...
... a member of the TNF receptor superfamily, is costimulatory to mouse T lymphocyte subpopulations". Eur J Immunol. 34 (3): 613-22 ... Surface expression of BTLA is gradually downregulated during differentiation of human CD8+ T cells from the naive to effector ... Binding with its two ligands are CD80 and CD86, expressed on dendritic cells, prompts T cell expansion. CD28 was the target of ... CD27 - This molecule supports antigen-specific expansion of naïve T cells and is vital for the generation of T cell memory. ...
... the T-cell receptor binding to an antigen-MHC complex and T-cell surface receptor CD28 binding to CD80 or CD86 proteins. CTLA4 ... Furthermore, antibodies targeting the co-stimulatory protein CD40 require engagement with selective Fc receptors for optimal ... Dendritic cell therapies include the use of antibodies that bind to receptors on the surface of dendritic cells. Antigens can ... Those that bind to tumor antigens treat cancer. Cell surface receptors are common targets for antibody therapies and include ...
... is a protein expressed on antigen-presenting cells that provides costimulatory signals necessary for T cell activation and ... Cluster of differentiation CD80 CD28 CTLA-4 List of human clusters of differentiation for a list of CD molecules GRCh38: ... It is the ligand for two different proteins on the T cell surface: CD28 (for autoregulation and intercellular association) and ... in systemic lupus erythematosus is associated with an altered expression of low-affinity Fc gamma receptors and costimulatory ...
It is a weak mu-opioid receptor (MOR) agonist, but does not have significant affinity for known neurotransmitter receptors. ... "5c8 Antigen". Google Patents. Google. Retrieved 21 December 2011. "Methods of inhibiting an autoimmune response in a human ... Lederman S; Yellin MJ; Krichevsky A; Belko J; Lee JJ; Chess L (April 1992). "Identification of a novel surface protein on ... and enhance their costimulatory activity". J. Immunol. 153 (2): 666-74. PMID 7517421. Yellin MJ, Sippel K, Inghirami G, et al ...
CD69 Sphingosine-1-phosphate receptors S1PR1 S1PR2 S1PR3 S1PR4 S1PR5 Co-stimulatory molecules CD80 - Expressed by APCs CD86 - ... T cells Antigen receptor - T cell receptor (TCR) Subunits - [email protected] / [email protected] / [email protected] / [email protected] Co-receptors CD8 (CD8α / CD8β) CD4 ... Mucosal surfaces Respiratory tract antimicrobial defense system - Respiratory tract Neuroimmunology - Neuroimmune system in the ... Anaphylatoxin receptors C3a receptor C5a receptor (CD88) C5AR2 Fc receptor Fc-gamma receptors (FcγR) FcγRI (CD64) FcγRIIA ( ...
As a result, the macrophage expresses more CD40 and TNF receptors on its surface, which helps increase the level of activation ... B cells can present antigens to a specialized group of helper T cells called TFH cells. If an activated TFH cell recognizes the ... CD154 acts as a costimulatory molecule and is particularly important on a subset of T cells called T follicular helper cells (T ... Receptor/signaling modulators. Signaling peptide/protein receptor modulators. Growth factor receptor modulators. ...
Another method combines iPSC and chimeric antigen receptor (CAR) technologies to generate human T cells targeted to CD19, an ... which effectively clears the cell surface from TGF-β receptor type II and selectively inhibits intracellular TGF-β signaling. ... Cd80, Ctsl, Pax1). mesenchymal stem/stromal cells (MSCs) are under investigation for applications in cardiac, renal, neural, ... which disrupts T cell costimulatory pathways and PD-L1, which activates T cell inhibitory pathway. See also: US 20130058900 ...
It is thought that these effects are mediated by opioid receptors expressed on the surface of these immune cells.[4] ... the TCR-antigen binding and causes conformational change or the removal of the entire TCR3/CD3 complex from the T-cell surface ... unless the cells receive another signal through a co-stimulatory molecule. CD3 antibodies shift the balance from Th1 to Th2 ... Its effects are mediated by the trimer cell surface receptor IL-2a, consisting of the α, β, and γ chains. The IL-2a (CD25, T- ...
receptor activity. • antigen binding. • virus receptor activity. • protein binding. • transmembrane signaling receptor activity ... Del Valle JM, Engel P, Martín M (2003). "The cell surface expression of SAP-binding receptor CD229 is regulated via its ... "Molecular dissection of the signaling and costimulatory functions of CD150 (SLAM): CD150/SAP binding and CD150-mediated ... STAT6, IRF4, and NF-kB factors involved in the transfer of the signals from the B-cell receptor, its co-receptors and IL-4R, ...
The CD4+/CD8+ ratio measures the ratio of T helper cells to cytotoxic T cells. The CD4+/CD8+ ratio in the peripheral blood of healthy adults and mice is about 2:1, and an altered ratio can indicate diseases relating to immunodeficiency or autoimmunity. An inverted CD4+/CD8+ ratio (namely, less than 1/1) indicates an impaired immune system. A reduced CD4+/CD8+ ratio is associated with reduced resistance to infection. Patients with tuberculosis show a reduced CD4+/CD8+ ratio. A declining CD4+/CD8+ ratio is associated with ageing, and is an indicator of immunosenescence. A study of elderly humans showed the highest expansion of cytotoxic T cells among those with cytomegalovirus. In obese adipose tissue, pro-inflammatory CD8+ cells increase and recruit macrophages, predominating over ...
Activation of CD4+ T cells occurs through the simultaneous engagement of the T-cell receptor and a co-stimulatory molecule (like CD28, or ICOS) on the T cell by the major histocompatibility complex (MHCII) peptide and co-stimulatory molecules on the APC. Both are required for production of an effective immune response; in the absence of co-stimulation, T cell receptor signalling alone results in anergy. The signalling pathways downstream from co-stimulatory molecules usually engages the PI3K pathway generating PIP3 at the plasma membrane and recruiting PH domain containing signaling molecules like PDK1 that are essential for the activation of PKCθ, and eventual IL-2 production. Optimal CD8+ T cell response relies on CD4+ signalling.[33] CD4+ cells are useful in the initial antigenic activation of naïve CD8 T cells, and sustaining memory CD8+ T cells in the aftermath of an acute infection. ...
Activation of CD4+ T cells occurs through the simultaneous engagement of the T-cell receptor and a co-stimulatory molecule (like CD28, or ICOS) on the T cell by the major histocompatibility complex (MHCII) peptide and co-stimulatory molecules on the APC. Both are required for production of an effective immune response; in the absence of co-stimulation, T cell receptor signalling alone results in anergy. The signalling pathways downstream from co-stimulatory molecules usually engages the PI3K pathway generating PIP3 at the plasma membrane and recruiting PH domain containing signaling molecules like PDK1 that are essential for the activation of PKC-θ, and eventual IL-2 production. Optimal CD8+ T cell response relies on CD4+ signalling.[33] CD4+ cells are useful in the initial antigenic activation of naïve CD8 T cells, and sustaining memory CD8+ T cells in the aftermath of an acute infection. ...
Activation of CD4+ T cells occurs through the simultaneous engagement of the T-cell receptor and a co-stimulatory molecule (like CD28, or ICOS) on the T cell by the major histocompatibility complex (MHCII) peptide and co-stimulatory molecules on the APC. Both are required for production of an effective immune response; in the absence of co-stimulation, T cell receptor signalling alone results in anergy. The signalling pathways downstream from co-stimulatory molecules usually engages the PI3K pathway generating PIP3 at the plasma membrane and recruiting PH domain containing signaling molecules like PDK1 that are essential for the activation of PKCθ, and eventual IL-2 production. Optimal CD8+ T cell response relies on CD4+ signalling.[33] CD4+ cells are useful in the initial antigenic activation of naïve CD8 T cells, and sustaining memory CD8+ T cells in the aftermath of an acute infection. ...
HIV infection leads to a progressive reduction in the number of T cells expressing CD4. Medical professionals refer to the CD4 count to decide when to begin treatment during HIV infection, although recent medical guidelines have changed to recommend treatment at all CD4 counts as soon as HIV is diagnosed. A CD4 count measures the number of T cells expressing CD4. While CD4 counts are not a direct HIV test-e.g. they do not check the presence of viral DNA, or specific antibodies against HIV-they are used to assess the immune system of a patient.[citation needed] National Institutes of Health guidelines recommend treatment of any HIV-positive individuals, regardless of CD4 count[17] Normal blood values are usually expressed as the number of cells per microliter (μL, or equivalently, cubic millimeter, mm3) of blood, with normal values for CD4 cells being 500-1200 cells/mm3.[18] ...
La CD154, anche chiamata CD40 ligando o semplicemente CD40L, è una proteina espressa soprattutto nei linfociti T attivati e facente parte della superfamiglia del TNF[1]. Si lega al CD40 presente sulle antigen-presenting cell (APC) agendo come co-attivatore[1]. In particolare, il legame CD40/CD40L attiva i linfociti B stimolandoli a formare i centri germinativi, porta le cellule dendritiche ad aumentare la produzione di molecole stimolatorie e citochine (licensing delle cellule dendritiche), e aumenta l'attività microbicida dei macrofagi. ...
CD4+ T细胞的激活需要T细胞上的TCR和共受体(CD28或ICOS),抗原呈递细胞上的MHCII和共激活分子两对分子的分别,同时结合。仅其中一对的结合,无法产生有效的T细胞激活。理想的CD8+ T细胞激活则依赖于CD4+ T细胞的信号转导[28]。CD4+细胞可以在初级CD8 T细胞的初次免疫应答中给予帮助,并且在急性感染的后期维持CD8+ 记忆T细胞的活性。所以,CD4+ T的激活对于CD8+ T细胞的活动是有利的[29][30][31]。 相比于MHC分子上的抗原,抗原呈递细胞的共激活分子一般是由病原体的副产物、热休克蛋白或者坏死的细胞碎片诱导表达的。共刺激机制被认为可以避免自体免疫的发生,因为即使T细胞错误地结合了自体抗原,也可能因为没有受到合适的共刺激而无法正常活化。一旦T细胞被正确地活化,它的细胞表面蛋白表达就会发生巨大的改变,活化T细胞的标志蛋白包括CD69,CD71,CD25 ...
ഒരുപോലെയിരിക്കുന്ന ശരാശരി വലിപ്പമുള്ള ലിംഫോസൈറ്റുകളാണ് സൂക്ഷ്മദർശിനിയിലൂടെ ദൃശ്യമാവുക. 'നക്ഷത്രപൂരിതമായ ആകാശം' എന്നാണ് ഈ സൂക്ഷ്മദർശിനി ദൃശ്യത്തെ വിശേഷിപ്പിക്കുന്നത്.[4] ഈ ലിംഫോസൈറ്റുകൾക്ക് ക്ഷാരാഭിമുഖ്യമുള്ള കോശദ്രവ്യം ഉണ്ടാകും. 'ചെറിയ മുറിയാത്ത കോശങ്ങൾ' എന്നാണ് ബർക്കിറ്റ് ലിംഫോമയിലെ ലിംഫോസൈറ്റുകളെ വിശേഷിപ്പിക്കുന്നത്. ബി-കോശ വ്യതിരക്ത മാർക്കറുകളായ CD20, CD22, CD19 എന്നിവ ...
Yn aml mae gan enynnau lawer o gyfystyron. Mae hyn oherwydd eu bod yn aml yn cael eu darganfod gan nifer o bobl mewn cyd-destunau gwahanol heb wybod mai'r un genynnau oeddyn nhw. Hefyd mae gan wahanol gymunedau gwyddonol safonau gwahanol ar gyfer enwi genynnau. Dyma restr o gyfystyron ar gyfer y genyn CD40. ...
Carcinoembryonic antigen-related cell adhesion molecule 8 (CEACAM8) also known as CD66b (Cluster of Differentiation 66b), is a member of the carcinoembryonic antigen (CEA) gene family. Its main function is cell adhesion, cell migration, and pathogen binding. CEACAM8 is expressed exclusively on granulocytes and used as granulocyte marker. Cluster of differentiation GRCh38: Ensembl release 89: ENSG00000124469 - Ensembl, May 2017 "Human PubMed Reference:". "Entrez Gene: CEACAM8 carcinoembryonic antigen-related cell adhesion molecule 8". Khan WN, Frängsmyr L, Teglund S, et al. (1992). "Identification of three new genes and estimation of the size of the carcinoembryonic antigen family". Genomics. 14 (2): 384-90. doi:10.1016/S0888-7543(05)80230-7. PMID 1427854. Oikawa S, Inuzuka C, Kuroki M, et al. (1991). "A specific heterotypic cell adhesion activity between members of carcinoembryonic antigen family, W272 and NCA, is mediated by N-domains". J. Biol. Chem. 266 (13): 7995-8001. PMID 2022629. ...
Carcinoembryonic antigen-related cell adhesion molecule 7 is a protein that in humans is encoded by the CEACAM7 gene. ENSG00000007306 GRCh38: Ensembl release 89: ENSG00000280501, ENSG00000007306 - Ensembl, May 2017 "Human PubMed Reference:". Thompson J, Zimmermann W, Nollau P, Neumaier M, Weber-Arden J, Schrewe H, Craig I, Willcocks T (Jan 1995). "CGM2, a member of the carcinoembryonic antigen gene family is down-regulated in colorectal carcinomas". J Biol Chem. 269 (52): 32924-31. PMID 7806520. Thompson J, Seitz M, Chastre E, Ditter M, Aldrian C, Gespach C, Zimmermann W (May 1997). "Down-regulation of carcinoembryonic antigen family member 2 expression is an early event in colorectal tumorigenesis". Cancer Res. 57 (9): 1776-84. PMID 9135022. "Entrez Gene: CEACAM7 carcinoembryonic antigen-related cell adhesion molecule 7". Human CEACAM7 genome location and CEACAM7 gene details page in the UCSC Genome Browser. Douard R, Wind P, Sales JP, et al. (2006). "Long-term prognostic value of detection of ...
Carcinoembryonic antigen-related cell adhesion molecule 6 (non-specific cross reacting antigen) (CEACAM6) also known as CD66c (Cluster of Differentiation 66c), is a member of the carcinoembryonic antigen (CEA) gene family.. Cluster of differentiation GRCh38: Ensembl release 89: ENSG00000086548 - Ensembl, May 2017 "Human PubMed Reference:". "Entrez Gene: CEACAM6 carcinoembryonic antigen-related cell adhesion molecule 6 (non-specific cross reacting antigen)". Oikawa S, Inuzuka C, Kuroki M, et al. (1991). "A specific heterotypic cell adhesion activity between members of carcinoembryonic antigen family, W272 and NCA, is mediated by N-domains". J. Biol. Chem. 266 (13): 7995-8001. PMID 2022629. Haus O, Noworolska A, Laskowski M, et al. (1990). "Prognostic significance of secondary cytogenetic changes and nonspecific cross-reacting antigen (NCA) in patients with Ph-positive chronic myeloid leukemia". Exp. Mol. Pathol. 52 (2): 235-42. doi:10.1016/0014-4800(90)90008-2. PMID 2332039. Hefta SA, Paxton ...
Leukocyte surface antigen CD53 is a protein that in humans is encoded by the CD53 gene. The protein encoded by this gene is a member of the transmembrane 4 superfamily, also known as the tetraspanin family. Most of these members are cell-surface proteins that are characterized by the presence of four hydrophobic domains. The proteins mediate signal transduction events that play a role in the regulation of cell development, activation, growth and motility. This encoded protein is a cell surface glycoprotein that is known to complex with integrins. It contributes to the transduction of CD2-generated signals in T cells and natural killer cells and has been suggested to play a role in growth regulation. Familial deficiency of this gene has been linked to an immunodeficiency associated with recurrent infectious diseases caused by bacteria, fungi and viruses. Alternative splicing results in multiple transcript ...
... by cognate antigen-presenting cell (APC) receptors (e.g. CD40, CD80, CD86) results in a state of T cell unresponsiveness, known ... Engagement of TCR without simultaneous activation of costimulatory molecules on T cell surface (e.g. CD40L, CD28) ... T-cell-receptor (TCR) engagement by antigen/MHC ligand initiates a complex signaling cascade culminating in the massive release ... 1999) Human G protein-coupled receptor GPR-9-6/CC chemokine receptor 9 is selectively expressed on intestinal homing t ...
GSH also increases the expressions of costimulatory molecules such as HLA-DR, CD80 and CD86 on the cell surface of DCs. ... MHC class II surface receptors, used to process and present antigens to naïve T cells. ... Figure 4: Immunocytochemical analysis of costimulatory marker expressions on the cell surface of DCs. Co-stimulatory marker ... to TCR receptors; additionally, a co-stimulatory activation must occur between CD28 molecule and CD80 and CD86 on APCs, the ...
... costimulatory signal. A major costimulatory pathway involves the binding of CD80 and CD86 molecules on the surface of antigen ... recognition of a specific antigen by a T cell receptor (signal 1) and a second, ... Abatacept selectively inhibits this costimulatory pathway by specifically binding to CD80 and CD86. Studies indicate that naive ... Abatacept decreases antigen specific TNFα, interferon-γ, and interleukin-2 production by T lymphocytes. ...
... if their T cell receptors recognize and bind the antigen on MHC complexes and their CD28 costimulatory receptors bind CD80 and ... antigen-presenting cells must provide costimulatory signals through surface receptors (such as CD28) and cytokines [such as ... The Immune Checkpoint Receptor PD-1. The surface receptor PD-1 (CD279) was first discovered on a murine T cell hybridoma and ... CTLA-4 may also remove CD80 and CD86 (including their cytoplasmic domains) from the cell surfaces of antigen-presenting cells ...
Fc receptor-mediated opsonization also enhances expression of costimulatory molecules such as CD40, B7-1 (CD80), and B7-2 (CD86 ... Numerous therapies increase the expression of tumor antigens on the tumor cell surface, increasing T cell receptor signaling ... while blocking antibodies to the co-inhibitory receptors cytotoxic T lymphocyte antigen 4 (CTLA4) and programmed death 1 (PD1) ... Therapies boosting DC antigen presentation and initial T cell priming should be delivered prior to vaccines and continued ...
CD80 and CD86 are ligands for CD28, which functions as a T cell costimulatory receptor. Interaction of CD28 with CD80 or CD86 ... Background: CD80 (B7-1, BB1) and CD86 (B7-2, B70) are members of the B7 family of cell surface ligands that regulate T cell ... CD80 is expressed on activated antigen presenting cells, including dendritic cells, B cells, monocytes, and macrophages. CD86 ... Background: c-Kit is a member of the subfamily of receptor tyrosine kinases that includes PDGF, CSF-1, and FLT3/flk-2 receptors ...
CD80 and CD86 are ligands for CD28, which functions as a T cell costimulatory receptor. Interaction of CD28 with CD80 or CD86 ... binding to its receptor LFA-1 (leukocyte function-associated antigen-1) on the surface of T cells during antigen presentation ( ... CD27 is one of the two most important co-stimulatory receptors for T cell priming (the other one is CD28). While CD28 co- ... Background: CD80 (B7-1, BB1) and CD86 (B7-2, B70) are members of the B7 family of cell surface ligands that regulate T cell ...
This very high affinity antibody blocks binding of CTLA4 to its natural receptor CD80 or CD86 at subnanomolar concentrations. ... were washed again and stained using a panel of fluorescein-labeled antibodies against the following T-cell surface antigens: ... the costimulatory molecules CD80 and CD86) decreases interleukin-2 transcription and T-cell activation (15). In addition, ... Extended surface analysis of the tumor-infiltrating CD3+/CD4− T cells in the regressing lesion showed that the cells had a HLA- ...
... such as Toll-like receptors (TLRs) (4⇓-6). Mature and activated DCs characteristically express cell surface costimulatory ... including CD80, CD86, and CD70, which stimulate antigen-specific CD8+ cytotoxic T cells to proliferate; (iii) ihv-DCs also ... CTL-mediated killing mandates the presence of an HLA molecule/CTA (cancer/testis antigen) on the surface of cancer cells, while ... these DCs can be modified genetically for investigating the role of existing or putative costimulatory receptors that mediate ...
3G). β-GlcCer also induced the up-regulation of surface expression of costimulatory molecules, such as CD40, CD80, CD86, and ... a C-type lectin receptor involved in dendritic cell cross-presentation of dead cell-associated antigens. Immunity 42:839-849. ... such as Toll-like receptors (TLRs), Nod-like receptors, RIG-I-like receptors, and C-type lectin receptors (CLRs) (1⇓⇓-4). ... H) Surface expression levels of CD80, CD40, CD86, and MHC class II on WT and Mincle−/− BMDCs stimulated with 24:1 β-GlcCer at ...
... as well as binding of the T cell costimulatory receptors to their cognate ligands that are expressed by the tumor or antigen ... CD28 is an important costimulatory molecule expressed on the T cell surface. There are two known ligands for CD28, CD80 (B7.1) ... antigen presenting cell. CAR. chimeric antigen receptor. CR. complete response. CTLA-4. cytotoxic-T-lymphocyte antigen. DLBCL. ... peptide/human leukocyte antigen complex. PR. partial response. SCT. stem cell transplantation. TCR. T cell receptor. TIL. tumor ...
CD80 (B7-1) antibody Mouse Monoclonal from Proteintech validated in Flow Cytometry (FC) applications. This antibody reacts with ... CD80 is the receptor for the proteins CD28 and CTLA-4 found on the surface of T-cells. It is involved in the costimulatory ... Activation B7 1 antigen, B7, B7 1, BB1, CD28LG, CD28LG1, CD80, CD80 molecule, CTLA 4 counter receptor B7.1, LAB7 ... 1X10^6 Daudi cells were surface stained with 0.5 ug PE-Anti-Human CD80 (B7-1) (PE-65083, clone 2D10.4) (red) or 0.5 ug PE-mouse ...
Naive T cell activation requires signaling by the T cell receptor and by nonclonotypic cell surface receptors. The most ... important costimulatory protein is the monovalent homodimer CD28, which interacts with CD80 and CD86 expressed on antigen- ... Naive T cell activation requires signaling by the T cell receptor and by nonclonotypic cell surface receptors. The most ... Insulin-like growth factor II receptor (IGF2R) is a multifunctional cell surface receptor implicated in tumour suppression. Its ...
... type of DC maturation stimulus received and on the interaction of T-cell costimulatory molecules with their surface receptors ... Upon encountering a dendritic cell presenting a cognate tumor antigen-derived peptide epitope and expressing B7 costimulatory ... Thus, interaction of CD28 or OX40 with CD80/86 or OX40L will promote potentially protective T cell responses, while interaction ... These surface proteins are typically members of either the TNF receptor or B7 superfamilies. Agonistic antibodies directed ...
... express similar cell surface levels of the MHC class II molecule HLA-DR as well as the costimulatory molecules CD40 and CD80, ... Important receptors include TLRs, cytosolic NOD like receptors (NLRs), C-type lectin receptors, and DC-SIGN [88-90]. Among the ... and present M.tb antigens to naïve antigen-specific T cells in the lymph node [39, 75-77]. DC populations that reside in lung ... Some pattern-recognition receptors also elicit an anti-inflammatory response in response to M.tb. The mannose receptor is a C- ...
The combination of intracellular signals generated by the antigen receptor, coreceptor (CD4+ or CD8+) and costimulatory ... CD28 + CD80 (B7-1) The second but primary signal of the costimulatory pathway involved in T cell activation occurs when CD28 on ... is a stimulatory receptor expressed on the surface of activated CD4+ and CD8+ T cells and NK cells upon initiation of CD28 ... the T-cell surface binds to one or both of the B7 molecules, B7-1 (CD80) and B7-2 (CD86), on the APC. ...
Mature DCs also upregulate chemokine receptors, notably CCR7, that enables effective migration to lymph nodes for antigen ... matured DCs revealed a significant increase in surface expression of CD80, CD83, CD25, and CCR7 as compared with pulsed ... or no antigen in the presence of costimulatory monoclonal antibodies (mAb), anti-CD28 and anti-CD49d (1 μg/mL of each, BD ... Conserved and truly tumor-specific antigens, such as EGFRvIII, can serve as potent antigens for tumor rejection but are rare in ...
... through its inhibitory receptor CTLA-4 that bounds to the costimulatory molecules CD80 and CD86, expressed on the surface of ... and their cognate antigens, presented by medullary thymic epithelial cells and hematopoietic antigen-presenting cells, leading ... CTLA-4 suppresses the T cell response by interacting with costimulatory receptors CD80 and CD86, expressed at the APC surface. ... CTLA-4 competes with the CD28 receptor present on the surface of effector T cells (Teff) and inhibits costimulatory signals ...
... including antigen-presentation molecules (MHC class II), co-stimulatory receptors (CD40, CD80, CD86), maturation markers (CD83 ... IPP stimulation results in surface expression of multiple receptors commonly associated with DC, ... including DC-like antigen-presenting and co-stimulatory molecules as well as the ability to induce antigen-specific CD4+ and ... γδT-antigen-presenting cells (APC), activated γδT cells with antigen-presentation function, might be a valuable alternative to ...
CpG ODN-conjugated NPs induced maturation of BMDCs as evidenced by the overexpression of CD80 and CD40 co-stimulatory receptors ... treated with the SIINFEKL-conjugated NPs efficiently cross-presented the antigenic peptide via MHC-I surface receptor and ... Reduction sensitive PEG hydrogels for co-delivery of antigen and adjuvant to induce potent CTLs. by Logan Thomison , Aug 29, ... Eliciting antigen specific cytotoxic T cells (CTLs), CD8+ effector T cells, are essential in controlling intracellular ...
Activation of CD4 T cells requires the engagement of the T cell receptor (TCR) by antigen-MHC-II complexes on the surface of ... In addition, full T cell activation requires interaction between the molecule CD28 on the T cell and its ligands CD80 and CD86 ... immune aging is the accumulation of end-differentiated effector CD4 T cells that lack expression of the costimulatory receptor ... CD4 T cell activation is initiated by interaction of the TCR with the antigen-MHC-II expressed on the surface of an APC. ...
During maturation, DC increase the surface expression of co-stimulatory molecules such as CD38, CD40, CD80 CD86, and CD83 [23] ... Antigen uptake by DC induces maturational changes that include decreased expression of the chemokine receptors CCR1, CCR2, and ... In contrast, stimulation with rgHMPV or rgHRSV had only moderate effects on chemokine receptor surface expression. Cell surface ... 2. Cell surface expression of the chemokine receptors CCR1, 2, 5 and 7. Immature MDDC were stimulated with LPS or infected with ...
... antigen-MHC complexes by the T cell antigen receptor is not sufficient for activation of naïve T cells-additional costimulatory ... signals (4, 5) are required that are provided by the engagement of CD28 on the T cell surface with B7 molecules (CD80 and CD86 ... T cell activation occurs only after interaction between T cell receptor (TCR) and antigen in the context of MHC (signal 1) plus ... The tumor antigens can be derived from oncogenic viruses, differentiation antigens, epigenetically regulated molecules such as ...
... co-stimulatory molecules like CD80 and CD86, which are essential for antigen presentation and activation of T-lymphocytes. ... toll-like receptors, C-type lectins, or complement receptors) abundantly expressed on the cell surface, iDCs undergo major ... During this maturation process, receptors for antigen capture are down-regulated, whereas molecules essential for antigen ... Additionally, the expression of chemokine receptor CCR7 on the cell surface is induced, which enables the migration of DCs from ...
... of co-stimulatory molecules particularly T-cell surface specific glycoprotein CD28 with T-cell activation antigens CD80 and ... Fully owned owned by Alligator, ATOR-1015 binds to two different immune receptors: the checkpoint receptor CTLA-4 and the co- ... a co-stimulatory receptor on the antigen presenting cells that is essential for activating both innate and adaptive immunity.. ... antigen recognition through the T cell receptor (TCR) and major histocompatibility complex (MHC); and co-stimulatory or co- ...
  • Whereas osteoclasts and osteoblasts are the main regulators of bone homeostasis, recent studies underscore a key role for the immune system, particularly via activation-induced T lymphocyte production of receptor activator of NFκB ligand (RANKL). (natap.org)
  • The targets of such therapies are CTLA-4 and PD-1 receptors, both expressed on the T cell surface, and PD-1 ligand PD-L1. (biomedcentral.com)
  • Orencia is a recombinant fusion protein that consists of the extracellular ligand-binding domain of human cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) linked to a modified Fc region of human immunoglobulin G1 (IgG1). (ancavasculitisnews.com)
  • These immunotherapies consist of immune system checkpoint inhibitors, such as for example monoclonal antibodies aimed against cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and designed cell death proteins-1 (PD-1)/designed cell loss of life Axitinib ligand-1 (PD-L1) pathway, that have showed therapeutic efficacy in a number of individual malignancies, including those regarded as non-immunogenic historically, including lung cancers (5-7). (capecodmushroom.org)
  • The presumptive effect is suboptimal triggering of T-cell receptor signaling. (aacrjournals.org)
  • Understanding the events in generating and regulating anti-tumor immunity suggests at least three sites for therapeutic intervention: promoting the antigen presentation functions of DCs, promoting the production of protective T cell responses, and overcoming immunosuppression in the tumor bed. (nih.gov)
  • These include the upregulation of PD-L1/L2 on the cancer cell surface, release of PGE2, arginase and IDO (all T cell suppressors), and the release of VEGF (triggered in part by intratumoral hypoxia), which inhibits T cell diapedesis from the vasculature and thus infiltration into the tumor bed. (nih.gov)
  • The recognition of antigen by T cell receptors provides specificity to the response. (fitness-vip.com)
  • This is one of the best characterized T cell costimulatory pathways. (fitness-vip.com)
  • T cell receptor (TCR) down‐modulation after antigen presentation is a fundamental process that regulates TCR signal transduction. (embopress.org)
  • antigen‐specific inflammatory arthritis and a T cell‐derived lymphoma. (embopress.org)
  • One cell surface marker that has been associated with TRM is the integrin αeβ7. (wikipedia.org)
  • the H 4 receptor exerts a chemotactic effect on several cell types associated with allergy and asthma. (springer.com)
  • This system of protein ubiquitination plays a key role in many cellular processes, such as the regulation of the cell cycle, modulation of cell surface receptors, cellular differentiation, DNA repair, gene transcription, and cellular stress responses. (biomedcentral.com)
  • The T cell receptor must first interact with the Major histocompatibility complex (MHC) surface protein. (wikipedia.org)
  • Discovery of the immune checkpoints cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) and programmed cell death protein 1 (PD-1) as key regulators of the adaptive immune response motivated the development of immune checkpoint blockade (ICB) therapeutics targeting these pathways. (biomedcentral.com)
  • CD3ζ, also known as T-cell receptor zeta, which together with T-cell receptor and CD3γ, δ , ε chain, forms the TCR-CD3 complex. (creative-biolabs.com)
  • demonstrated that patients with advanced renal cell carcinoma given a combination of nivolumab and ipilimumab had an increased survival versus sunitinib (a multi-targeted receptor tyrosine kinase inhibitor) at 18 months (75% overall survival versus 60%, respectively) . (jizak.info)
  • CD80 appears to play a role distinct from CD80 in T helper cell differentiation. (fishersci.com)
  • This antibody has been used in multiple FACS experiments for various immunological applications, such as to demonstrate how the C-type lectin receptor DCIR modulates immunity to tuberculosis (Troegeler et al, 2017), to elucidate the mechanism of Th17 cell differentiation by cholera toxin (Kang et al, 2016), and to evaluate the role of the spleen tyrosine kinase in graft-versus-host disease (Flynn et al, 2015). (absoluteantibody.com)
  • PD-1 signaling also activates Cbl-b and Smad3, which downregulate cell surface expression of the TCR and cell proliferation, respectively, inhibits the antiapoptotic gene Bcl-x L , and activates the proapoptotic gene Bim. (jimmunol.org)
  • 2008. The PD-1/PD-L1 complex resembles the antigen-binding Fv domains of antibodies and T cell receptors. (jimmunol.org)
  • B cell CD80 expression was higher in women with HAM/TSP, underscoring that immune markers can reflect the female predominance observed in most autoimmune diseases. (biomedcentral.com)
  • Muc1 is the only cell surface mucin or MUC gene product that is expressed in DC. (elsevier.com)
  • When a T-cell is activated through its receptor, it can orchestrate protection from infection or autoimmunity, depending on the target. (diabetesjournals.org)
  • The adaptive immune system depends on the ability to assemble rearranged genes for both the T-cell receptor (TCR) and the immunoglobulin gene. (diabetesjournals.org)
  • Background Signaling through the B-cell receptor appears to be a major contributor to the pathogenesis of chronic lymphocytic leukemia. (haematologica.org)
  • Design and Methods We profiled the expression of genes associated with Toll-like receptor signaling pathways in 192 cases of chronic lymphocytic leukemia and explored potential associations with molecular features of the clonotypic B-cell receptors. (haematologica.org)
  • Significant differences were identified for selected genes between cases carrying mutated or unmutated IGHV genes or assigned to different subsets with stereotyped B-cell receptors. (haematologica.org)
  • A role for antigen in the development of chronic lymphocytic leukemia (CLL) is strongly suggested by the biased immunoglobulin heavy variable ( IGHV ) gene repertoire of the malignant clones, the prognostic implications of IGHV gene mutational status and the identification of subsets of patients with almost identical, stereotyped B-cell receptors (BcR), who can also exhibit restricted demographic, biological and clinical features. (haematologica.org)
  • Over the past years, a number of factors have been identified to affect helper T cell lineage determination, including antigen receptor, coreceptors and, most importantly, cytokine environment. (biomedcentral.com)
  • The relevance of this pathway as a therapeutic target in RA has been demonstrated by clinical results obtained with abatacept (ABA), a cytotoxic T lymphocyte-associated antigen 4 immunoglobulin (CTLA-4-Ig) fusion protein 8 . (jrheum.org)
  • Upon the uptake of in the lungs, DCs process cryptococcal antigens after its initial elaboration Sotrastaurin kinase activity assay within endosomal/lysosomal pathway and present it in the context of the major histocompatibility complexes (MHCI and MHCII) [10,38C (monossabios.com)
  • VacA, an H. pylori virulence factor, was reported to interfere with proteolytic processing of tetanus toxoid and was shown to inhibit the Ii-dependent pathway of antigen presentation ( 38 ). (asm.org)
  • CD80 plays a role in induction of innate immune responses by activating NF-κB-signaling pathway in macrophages. (acrobiosystems.com)
  • However, because innate recognition of disease-specific antigens is a prerequisite for adaptive immune responses to occur, we begin by briefly introducing atherosclerosis-relevant antigens recognized by innate immunity. (jci.org)
  • The zeta chain plays an important role in coupling antigen recognition to several intracellular signal-transduction pathways. (creative-biolabs.com)
  • 4 The nature of the selecting antigens, the mechanistic aspects of their recognition by the clonotypic BcR and the functional impact of antigenic stimulation through the BcR remain largely unknown. (haematologica.org)
  • Here, we review the various biological pathways and emerging biomarkers implicated in response to PD-(L)1 and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) therapies, including oncogenic signaling pathways, human leukocyte antigen (HLA) variability, mutation and neoantigen burden, microbiome composition, endogenous retroviruses (ERV), and deficiencies in chromatin remodeling and DNA damage repair (DDR) machinery. (biomedcentral.com)
  • The vast majority of adaptors, effectors and members of the NFKB, JNK/p38, NF/IL6 and IRF pathways are intermediately-to-highly expressed, while inhibitors of Toll-like receptor activity are generally low-to-undetectable, indicating that the Toll-like receptor-signaling framework is competent in chronic lymphocytic leukemia. (haematologica.org)
  • DCs are central mediators between the innate and adaptive immune system and play an important role in capturing, processing, and presenting antigens ( 5 , 6 ). (asm.org)
  • Abatacept is a soluble fusion protein, which links the extracellular domain of human cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) to the modified Fc (hinge, CH2, and CH3 domains) portion of human immunoglobulin G1 (IgG1). (drugbank.ca)
  • Known as a recombinant fusion protein, the drug consists of the extracellular domain of human cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) linked to a modified Fc portion of human immunoglobulin G 1 (IgG 1 . (drugbank.ca)
  • Antigen uptake by DC induces maturational changes that include decreased expression of the chemokine receptors CCR1, CCR2, and CCR5 that maintain DC residence in peripheral tissues, and increased expression of CCR7 that mediates the migration of antigen-bearing DC to lymphatic tissue. (prolekare.cz)
  • Another study used a murine collagen-induced arthritis model, involving breaking tolerance to an endogenous antigen (collagen). (justia.com)
  • As the main target for a potential vaccine is the (overexpressed / mutated) p53 protein we will focus on studies aimed at the induction of humoral and cellular responses against this antigen. (biomedcentral.com)
  • Subunit vaccines represent one of these approaches since they have the potential to develop specific responses and entail the added benefits of allowing the incorporation of different antigens in a single vaccine ( 4 , 5 , 10 , 51 , 54 ). (asm.org)
  • They act to communicate the presence of pathogens to the adaptive immune system thereby initiating long lasting, antigen-specific responses. (aacrjournals.org)