Foreign substances that can infiltrate the body, including bacteria, fungi, parasites, toxic chemicals, and abnormal body cells, prompting the production of antibodies that attempt to destroy the subs [..]

a foreign substance in an organism which triggers the production of an antibody (immune reaction).

Antigens are non-self markers, often proteins, that alert cells of the immune system to the presence of potential danger. These antigens may pose no threat on their own – they are just components, suc [..]

Substances that are recognized by the Immune System and induce an immune reaction.

Antibodies to the Hepatitis B Antigens, including Antibodies to the surface (Australia) and core of the Dane particle and those to the "e" Antigens.

Substances of archaeal origin that have antigenic activity.

Endogenous Tissue constituents that have the ability to interact with Autoantibodies and cause an immune response.

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 stimula [..]

Substances elaborated by Bacteria that have antigenic activity.

Sets of Cell Surface Antigens located on Blood Cells. They are usually Membrane Glycoproteins or Glycolipids that are antigenically distinguished by their carbohydrate moieties.

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 subpopula [..]

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 An [..]

Also known as CD104 Antigen, this protein is distinguished from other beta Integrins by its relatively long cytoplasmic domain (approximately 1000 Amino Acids vs. approximately 50). Five alternatively [..]

Cytokine-induced Cell Adhesion molecule present on activated Endothelial Cells, Tissue Macrophages, dendritic Cells, Bone Marrow Fibroblasts, Myoblasts, and Myotubes. It is important for the recruitme [..]

An abundant lysosomal-associated Membrane Protein that has been found to shuttle between Lysosomes; Endosomes; and the Plasma Membrane. In Platelets and T-Lymphocytes it may play a Role in the cellula [..]

An abundant lysosomal-associated Membrane Protein that has been found to shuttle between Lysosomes; Endosomes; and the Plasma Membrane. Loss of expression of lysosomal-associated Membrane Protein 2 is [..]

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, Leuko [..]

Cell Surface Receptors that are specific for Thrombopoietin. They signal through interaction with Janus Kinases such as Janus Kinase 2.

A receptor for Macrophage Colony-Stimulating Factor encoded by the c-fms Proto-Oncogene (Genes, fms). It contains an intrinsic Protein-Tyrosine Kinase activity. When activated the receptor undergoes a [..]

Receptors that bind and internalize the Granulocyte-Macrophage stimulating factor. Their MW is believed to be 84 kD. The most mature myelomonocytic Cells, specifically Human Neutrophils, Macrophages, [..]

A Protein-Tyrosine Kinase Receptor that is specific for Stem Cell Factor. This interaction is crucial for the development of hematopoietic, gonadal, and pigment Stem Cells. Genetic Mutations that disr [..]

A receptor subunit that combines with Cytokine Receptor gp130 to form the dual specificity receptor for Leukemia Inhibitory Factor and Oncostatin M. The subunit is also a component of the Ciliary Neur [..]

An alpha-integrin subunit found on Lymphocytes, Granulocytes, Macrophages and Monocytes. It combines with the Integrin beta2 subunit (CD18 Antigen) to form Lymphocyte Function-Associated Antigen-1.

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.

A Tumor Necrosis Factor Receptor subtype that has specificity for Tumor Necrosis Factor alpha and Lymphotoxin alpha. It is constitutively expressed in most Tissues and is a key mediator of Tumor Necro [..]

A Tumor Necrosis Factor Receptor subtype that is expressed primarily in Immune System Cells. It has specificity for Membrane-bound form of Tumor Necrosis Factors and mediates intracellular-signaling t [..]

A receptor subunit that is a shared component of the Interleukin 2 Receptor and the Interleukin-15 Receptor. High affinity receptor complexes are formed with each of these receptors when their respect [..]

A low affinity Interleukin-3 Receptor subunit that combines with the Cytokine Receptor Common beta Subunit to form a high affinity receptor for Interleukin-3.

A receptor subunit that is a component of the Type I Interleukin-4 Receptor and the Type II Interleukin-4 Receptor. It signals through interaction of its cytoplasmic domain with Janus Kinases such as [..]

A low affinity Interleukin-5 Receptor subunit that combines with the Cytokine Receptor Common beta Subunit to form a high affinity receptor for Interleukin-5. Several Isoforms of the Interleukin-5 Rec [..]

A low affinity Interleukin-6 receptor subunit that combines with the Cytokine Receptor gp130 to form a high affinity receptor for Interleukin-6.

A low affinity Interleukin-7 receptor subunit that combines with the Interleukin Receptor Common gamma Subunit to form a high affinity receptor for Interleukin-7.

A Cell surface receptor that specifically mediates the biological effects of Interleukin-9. The functional IL9 receptor signals through interaction of its Cytoplasm domain with Janus Kinases and requi [..]

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-hematopo [..]

A Cytokine Receptor that acts through the formation of oligomeric complexes of itself with a variety of Cytokine Receptors.

A receptor subunit that is a shared component of the Interleukin-3 Receptor; the Interleukin-5 Receptor; and the GM-CSF Receptor. High affinity receptor complexes are formed with each of these recepto [..]

An Interleukin Receptor subunit that was originally discovered as a component of the Interleukin 2 Receptor. It was subsequently found to be a component of several other receptors including the Interl [..]

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 [..]

A receptor Tyrosine Kinase that is involved in Hematopoiesis. It is closely related to fms Proto-Oncogene Protein and is commonly mutated in Acute Myeloid Leukemia.

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 [..]

A Syndecan that interacts with Extracellular Matrix Proteins and plays a Role Cell Proliferation and Cell MIGRATION.

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 lipopo [..]

A PDGF Receptor that binds specifically to both PDGF-A chains and PDGF-B chains. It contains a Protein-Tyrosine Kinase activity that is involved in Signal Transduction.

A PDGF Receptor that binds specifically to the PDGF-B chain. It contains a Protein-Tyrosine Kinase activity that is involved in Signal Transduction.

Constituent composed of protein and phospholipid that is widely distributed in many Tissues. It serves as a cofactor with Factor VIIa to activate Factor X in the extrinsic pathway of Blood Coagulation [..]

A peptidyl-dipeptidase that catalyzes the release of a C-terminal dipeptide, -Xaa-*-Xbb-Xcc, when neither Xaa nor Xbb is Pro. It is a Cl(-)-dependent, Zinc Glycoprotein that is generally Membrane-boun [..]

A Cell Adhesion molecule of the Immunoglobulin superfamily that is expressed in Endothelial Cells and is involved in Intercellular Junctions.

A widely distributed Cell surface transmembrane Glycoprotein that stimulates the synthesis of Matrix Metalloproteinases. It is found at high levels on the surface of malignant Neoplasms and may play a [..]

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 Ant [..]

Tetraspanin Proteins found associated with Laminin-binding Integrins. The CD151 Antigens may play a Role in the Regulation of Cell MOTILITY.

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 Antig [..]

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.

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 liga [..]

A KIR Receptor that has specificity for HLA-C Antigens. It is an inhibitory receptor that contains D1 and D2 extracellular Immunoglobulin-like domains and a long cytoplasmic tail. It is similar in str [..]

A KIR Receptor that has specificity for HLA-C Antigen. It is an inhibitory receptor that contains D1 and D2 extracellular Immunoglobulin-like domains and a long cytoplasmic tail. It is similar in stru [..]

A KIR Receptor that has specificity for HLA-C Antigens. It is an inhibitory receptor that contains D1 and D2 extracellular Immunoglobulin-like domains and a long cytoplasmic tail. It is similar in str [..]

A KIR Receptor that has specificity for HLA-G Antigen. It contains D0 and D2 extracellular Immunoglobulin-like domains and a long cytoplasmic tail.

A KIR Receptor that has specificity for HLA-B Antigens. It is an inhibitory receptor that contains D0, D1, and D2 extracellular Immunoglobulin-like domains and a long cytoplasmic tail.

A KIR Receptor that has specificity for HLA-A3 Antigen. It is an inhibitory receptor that contains D0, D1, and D2 extracellular Immunoglobulin-like domains and a long cytoplasmic tail.

A Sialomucin protein that functions as a Cell Adhesion molecule. It is a negative regulator of certain types of Hematopoietic Stem Cells.

Cell Adhesion molecule expressed on activated Leukocytes, Fibroblasts, and Neurons. It is a ligand for CD6. ALCAM-CD6 interactions may play a Role in the binding of T and B Cells to activated Leukocyt [..]

A Sialic Acid binding lectin that was originally identified as an adhesion molecule for inflammatory Macrophages and activated Monocytes. This protein is the largest known Siglec subtype and contains [..]

A transmembrane protein belonging to the Tumor Necrosis Factor superfamily that was originally discovered on Cells of the lymphoid-myeloid lineage, including activated T-Lymphocytes and Natural Killer [..]

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 e [..]

CXCR Receptors that are expressed on the surface of a number of Cell types, including T-Lymphocytes; NK Cells; Dendritic Cells; and a subset of B-Lymphocytes. The receptors are activated by Chemokine [..]

CXCR Receptors isolated initially from Burkitt Lymphoma Cells. CXCR5 receptors are expressed on mature, recirculating B-Lymphocytes and are specific for Chemokine CXCL13.

Differentiation Antigens expressed on B-Lymphocytes and B-Cell precursors. They are involved in Regulation of B-Cell Proliferation.

CCR Receptors with specificity for a broad variety of CC Chemokines. They are expressed at high levels in Monocytes; Tissue Macrophages; Neutrophils; and Eosinophils.

CCR Receptors with specificity for Chemokine CCL2 and several other CCL2-related Chemokines. They are expressed at high levels in T-Lymphocytes; B-Lymphocytes; Macrophages; Basophils; and NK Cells.

CCR Receptors with specificity for Chemokine CCL11 and a variety of other CC Chemokines. They are expressed at high levels in T-Lymphocytes; Eosinophils; Basophils; and Mast Cells.

CCR Receptors with specificity for Chemokine CCL17 and Chemokine CCL22. They are expressed at high levels in T-Lymphocytes; Mast Cells; Dendritic Cells; and NK Cells.

CCR Receptors with specificity for Chemokine CCL3; Chemokine CCL4; and Chemokine CCL5. They are expressed at high levels in T-Lymphocytes; B-Lymphocytes; Macrophages; Mast Cells; and NK Cells. The CCR [..]

CCR Receptors with specificity for Chemokine CCL20. They are expressed at high levels in T-Lymphocytes; B-Lymphocytes; and Dendritic Cells.

CCR Receptors with specificity for Chemokine CCL19 and Chemokine CCL21. They are expressed at high levels in T-Lymphocytes; B-Lymphocytes; and Dendritic Cells.

A major histocompatibily complex class I-like protein that plays a unique Role in the presentation of lipid Antigens to Natural Killer T-Cells.

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, a [..]

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.

A lysosomal-associated Membrane Glycoprotein that is expressed at high levels in mature Dendritic Cells.

Molecular sites on or in B-Lymphocytes, Follicular Dendritic Cells, lymphoid Cells, and Epithelial Cells that recognize and combine with Complement C3d. Human Complement Receptor 2 (CR2) serves as a r [..]

An Interleukin Receptor subunit with specificity for Interleukin-13. It dimerizes with the Interleukin-4 Receptor alpha Subunit to form the Type II Interleukin-4 Receptor which has specificity for bot [..]

An Interleukin-13 Receptor subunit that is closely-related to the Interleukin-13 Receptor alpha1 Subunit. The receptor is found as a monomeric protein and has been considered to be a decoy receptor fo [..]

A lectin and Cell Adhesion molecule found in B-Lymphocytes. It interacts with Sialic Acids and mediates signaling from B-Cell Antigen Receptors.

Carbohydrate Antigen elevated in Patients with Tumors of the Breast, Ovary, Lung, and Prostate as well as other disorders. The Mucin is expressed normally by most glandular epithelia but shows particu [..]

Specific molecular sites on the surface of B- and T-Lymphocytes which combine with IgEs. Two subclasses exist: low affinity receptors (Fc epsilon RII) and high affinity receptors (Fc epsilon RI).

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.

A low affinity Interleukin-2 receptor subunit that combines with the Interleukin-2 Receptor beta Subunit and the Interleukin Receptor Common gamma-Chain to form a high affinity receptor for Interleuki [..]

A Tumor Necrosis Factor superfamily member that plays a Role in the Regulation of B-Lymphocyte Survival. It occurs as a Membrane-bound protein that is cleaved to release an biologically active soluble [..]

A Serine Protease that Catalyses the release of an N-terminal dipeptide. Several biologically-active Peptides have been identified as dipeptidyl peptidase 4 substrates including Incretins; Neuropeptid [..]

A Tumor Necrosis Factor Receptor superfamily member found expressed on peripheral B-Lymphocytes. It has specificity for B-Cell Maturation Antigen and Tumor Necrosis Factor Ligand Superfamily Member 13 [..]

A member of the Tumor Necrosis Factor Receptor superfamily that specifically binds B-Cell Activating Factor. It is found on B-Lymphocytes and plays a Role in maturation and Survival of B-Cells. Signal [..]

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 [..]

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 Cel [..]

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 [..]

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.

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 synthesi [..]

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 synt [..]

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 o [..]

Integrin beta-1 chains which are expressed as heterodimers that are noncovalently associated with specific alpha-chains of the CD49 Family (CD49a-f). CD29 is expressed on resting and activated Leukocy [..]

Cell Surface Receptors for Obesity factor (Leptin), a Hormone secreted by the White Adipocytes. Upon Leptin-receptor interaction, the signal is mediated through the JAK2/STAT3 pathway to regulate Food [..]

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.

A Cell Adhesion protein that is found within Tight Junctions of Endothelial Cells and on the Cell Membrane surface of circulating Platelets.

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 [..]

A 46-kD stimulatory receptor found on resting and activated Natural Killer Cells. It has specificity for Viral Hemagglutinins that are expressed on infected Cells.

A 44-kD stimulatory receptor found on activated Natural Killer Cells. It has specificity for Viral Hemagglutinins that are expressed on infected Cells.

A 30 kDa stimulatory receptor found on resting and activated Natural Killer Cells.

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 Ce [..]

Molecular sites on or in some B-Lymphocytes and Macrophages that recognize and combine with Complement C3b. The primary structure of these receptors reveal that they contain transmembrane and cytoplas [..]

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; S [..]

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 [..]

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 [..]

Platelet Membrane Glycoprotein IIb is an integrin alpha subunit that heterodimerizes with Integrin beta3 to form Platelet Glycoprotein GPIIb-IIIa Complex. It is synthesized as a single polypeptide cha [..]

A Sialic Acid-rich protein and an integral Cell Membrane Mucin. It plays an important Role in activation of T-Lymphocytes.

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 [..]

A full-length splicing isoform of CD45 Antigen.

A splicing isoform of CD45 Antigen that includes Exon A.

A splicing isoform of CD45 Antigen that includes Exon B.

A low Molecular Weight isoform of CD45 Antigen.

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 medi [..]

A ubiquitously expressed Membrane Glycoprotein. It interacts with a variety of Integrins and mediates responses to Extracellular Matrix Proteins.

An integrin alpha subunit that binds Collagen and Laminin though its I domain. It combines with Integrin beta1 to form the heterodimer Integrin alpha1beta1.

An integrin alpha subunit that primarily combines with Integrin beta1 to form the Integrin alpha2beta1 heterodimer. It contains a domain which has homology to Collagen-binding domains found in von Wil [..]

An integrin alpha subunit that occurs as alternatively spliced Isoforms. The Isoforms are differentially expressed in specific Cell types and at specific developmental stages. Integrin alpha3 combines [..]

An integrin alpha subunit that is unique in that it does not contain an I domain, and its proteolytic cleavage site is near the middle of the extracellular portion of the polypeptide rather than close [..]

This integrin alpha subunit combines with Integrin beta1 to form a receptor (Integrin alpha5beta1) that binds Fibronectin and Laminin. It undergoes posttranslational cleavage into a heavy and a Light [..]

An integrin alpha subunit that primarily associates with Integrin beta1 or Integrin beta4 to form Laminin-binding heterodimers. Integrin alpha6 has two alternatively spliced Isoforms: integrin alpha6A [..]

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 molec [..]

An alpha integrin with a Molecular Weight of 160-kDa that is found in a variety of Cell types. It undergoes posttranslational cleavage into a heavy and a Light chain that are connected by disulfide bo [..]

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.

A Cell-surface ligand involved in Leukocyte adhesion and Inflammation. Its production is induced by gamma-Interferon and it is required for Neutrophil migration into inflamed Tissue.

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, th [..]

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 a [..]

Oligosaccharide Antigenic Determinants found principally on NK Cells and T-Cells. Their Role in the immune response is poorly understood.

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 enha [..]

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 Mem [..]

An integrin beta subunit of approximately 85-kDa in size which has been found in Integrin alphaIIb-containing and Integrin alphaV-containing heterodimers. Integrin beta3 occurs as three alternatively [..]

Cell Adhesion molecule and CD Antigen that mediates Neutrophil, Monocyte, and Memory T-Cell Adhesion to cytokine-activated Endothelial Cells. E-selectin recognizes sialylated carbohydrate groups relat [..]

Cell Adhesion molecule and CD Antigen that serves as a homing receptor for Lymphocytes to Lymph Node high endothelial Venules.

Cell Adhesion molecule and CD Antigen that mediates the adhesion of Neutrophils and Monocytes to activated Platelets and Endothelial Cells.

Ubiquitously-expressed tetraspanin Proteins that are found in late Endosomes and Lysosomes and have been implicated in intracellular transport of Proteins.

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 [..]

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 ce [..]

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 [..]

A Glycoprotein enzyme present in various organs and in many Cells. The enzyme catalyzes the Hydrolysis of a 5'-ribonucleotide to a ribonucleoside and orthophosphate in the presence of Water. It i [..]

A component of the B-Cell Antigen Receptor that is involved in B-Cell Antigen Receptor heavy chain transport to the Plasma Membrane. It is expressed almost exclusively in B-Lymphocytes and serves as a [..]

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 prov [..]

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.

A widely expressed transmembrane Glycoprotein that functions as a Metastasis suppressor protein. It is underexpressed in a variety of Human Neoplasms.

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 prov [..]

An extracellular receptor specific for Urokinase-Type Plasminogen Activator. It is attached to the Cell Membrane via a Glycosylphosphatidylinositol LINKAGE and plays a Role in the co-localization of U [..]

A G-Protein-coupled receptor that signals an increase in intracellular Calcium in response to the potent ANAPHYLATOXIN peptide Complement C5a.

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 [..]

A LDL-receptor related protein involved in clearance of Chylomicron Remnants and of activated alpha-Macroglobulins from Plasma.

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 [..]

A heterodimeric protein that is a Cell Surface Antigen associated with Lymphocyte Activation. The initial characterization of this protein revealed one identifiable heavy chain (Antigens, CD98 Heavy C [..]

A transmembrane glycoProtein Subunit that can dimerize with a variety of Light chain subunits (Antigens, CD98 Light Chains). This Protein Subunit serves a diverse array of functions including amino ac [..]

A Family of Light chains that bind to the CD98 heavy chain (Antigens, CD98 Heavy Chain) to form a heterodimer. They convey functional specificity to the protein.

An Interleukin-1 receptor subtype that is involved in signaling cellular responses to Interleukin-1alpha and Interleukin-1beta. The binding of this receptor to its ligand causes its favorable interact [..]

An Interleukin-1 receptor subtype that competes with the Interleukin-1 Receptor Type I for binding to Interleukin-1alpha and Interleukin-1beta. The Interleukin-1 type II receptor appears to lack Signa [..]

High-affinity G-Protein-Coupled Receptors for Interleukin-8 present on Neutrophils; Monocytes; and Basophils.

High-affinity G-Protein-Coupled Receptors for Interleukin-8 present on Neutrophils; Monocytes; and T-Lymphocytes. These receptors also bind several other CXC Chemokines.

CCR Receptors with specificity for Chemokine CCL1. They are expressed at high levels in T-Lymphocytes; B-Lymphocytes; and Macrophages.

A subunit of the Interleukin-10 Receptor. It plays a Role in receptor signaling by associating with Janus Kinase 1.

A subunit of the Interleukin-10 Receptor. It plays a Role in receptor signaling by associating with TYK2 Kinase.

A subunit of the Interleukin-18 Receptor that is responsible of extracellular binding of IL-18.

A subunit of the Interleukin-18 Receptor that plays a Role in receptor signaling by Association of its cytoplasmic domain with Signal Transducing Adaptor Proteins such as Myeloid Differentiation Facto [..]

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 pla [..]

Membrane Antigens associated with maturation stages of B-Lymphocytes, often expressed in Tumors of B-Cell origin.

Retroviral Proteins, often glycosylated, coded by the envelope (env) Gene. They are usually synthesized as protein precursors (Polyproteins) and later cleaved into the final viral envelope Glycoprotei [..]

Substances of fungal origin that have antigenic activity.

Proteins coded by the retroviral gag Gene. The products are usually synthesized as protein precursors or Polyproteins, which are then cleaved by viral Proteases to yield the final products. Many of th [..]

The major group of Transplantation Antigens in the Mouse.

Any part or derivative of a Helminth that elicits an immune reaction. The most commonly seen Helminth Antigens are those of the schistosomes.

Antigens from any of the Hepatitis Viruses including surface, core, and other associated Antigens.

Antigens produced by various strains of Hepatitis A virus such as the Human hepatitis A virus (Hepatitis A Virus, Human).

Antigens of the Virion of the Hepatitis B virus or the Dane particle, its surface (Hepatitis B Surface Antigens), core (Hepatitis B Core Antigens), and other associated Antigens, including the Hepatit [..]

A closely related group of Antigens found in the Plasma only during the infective phase of Hepatitis B or in virulent Chronic Hepatitis B, probably indicating active Virus Replication; there are three [..]

Antigens produced by various strains of Hepatitis D Virus.

Polymorphic class I Human Histocompatibility (HLA) Surface Antigens present on almost all nucleated Cells. At least 20 Antigens have been identified which are encoded by the A locus of multiple Allele [..]

Class I Human Histocompatibility (HLA) Surface Antigens encoded by more than 30 detectable Alleles on locus B of the HLA complex, the most polymorphic of all the HLA specificities. Several of these An [..]

Class I Human Histocompatibility (HLA) Antigens encoded by a small cluster of structural Genes at the C locus on Chromosome 6. They have significantly lower immunogenicity than the HLA-A and -B determ [..]

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.

Class I Human Histocompatibility (HLA) Surface Antigens encoded by Alleles on locus B of the HLA complex. The HLA-G Antigens are considered non-classical Class I Antigens due to their distinct Tissue [..]

A group of the D-related HLA Antigens found to differ from the DR Antigens in Genetic Locus and therefore inheritance. These Antigens are polymorphic Glycoproteins comprising alpha and beta chains and [..]

A group of the D-related HLA Antigens (Human) found to differ from the DR Antigens in Genetic Locus and therefore inheritance. These Antigens are polymorphic Glycoproteins comprising alpha and beta ch [..]

Antigens from the House Dust Mites (DERMATOPHAGOIDES), mainly D. farinae and D. pteronyssinus. They are Proteins, found in Mite Feces or Mite extracts, that can cause Asthma and other allergic Disease [..]

Antigens associated with Human T-lymphotropic virus 1.

Antigens associated with Human T-lymphotropic virus 2.

Antigens associated with the Deltaretrovirus; HTLV-I Antigens and HTLV-II Antigens belong to this group.

A Family of RNA-Binding Proteins that are homologues of ELAV protein, Drosophila. They were initially identified in Humans as the targets of Autoantibodies in Patients with PARANEOPLASTIC Encephalomye [..]

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, eac [..]

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 Huma [..]

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; Eo [..]

A group of dominantly and independently inherited Antigens associated with the ABO Blood factors. They are Glycolipids present in Plasma and Secretions that may adhere to the Erythrocytes. The Phenoty [..]

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 [..]

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. [..]

A group of Lymphocyte Surface Antigens located on Mouse Lymphocytes. Specific Ly Antigens are useful markers for distinguishing subpopulations of Lymphocytes.

Antigens associated with specific Proteins of the Human Adult T-Cell immunodeficiency Virus (HIV); also called HTLV-III-associated and Lymphadenopathy-Associated Virus (LAV) Antigens.

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 use [..]

A Melanosome-specific protein that plays a Role in the expression, stability, trafficking, and processing of gp100 Melanoma Antigen, which is critical to the formation of Stage II Melanosomes. The pro [..]

Cellular Antigens that are specific for Melanoma Cells.

Endogenous Superantigens responsible for inducing strong proliferative responses in T-Cells in Mixed Lymphocyte Reactions (see Lymphocyte Culture Test, Mixed). They are encoded by Mouse mammary Tumor [..]

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 [..]

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.

Immunologically detectable substances found in the Cell Nucleus.

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 [..]

Substances found in Plants that have antigenic activity.

Human alloAntigens expressed only on Platelets, specifically on Platelet Membrane Glycoproteins. These Platelet-specific Antigens are immunogenic and can result in pathological reactions to transfusio [..]

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 [..]

Any part or derivative of any protozoan that elicits Immunity; Malaria (Plasmodium) and trypanosome Antigens are presently the most frequently encountered.

The protein components that constitute the common core of Small Nuclear Ribonucleoprotein particles. These Proteins are commonly referred as Sm Nuclear Antigens due to their antigenic Nature.

Cell-surface molecules that exhibit lineage-restricted patterns of expression during Embryonic Development. The Antigens are useful markers in the Identification of Embryonic Stem Cells.

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.

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 Ro [..]

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 comp [..]

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 rec [..]

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 [..]

A group of differentiation Surface Antigens, among the first to be discovered on Thymocytes and T-Lymphocytes. Originally identified in the Mouse, they are also found in other species including Humans [..]

Antigens which may directly stimulate B Lymphocytes without the cooperation of T Lymphocytes.

Antigens expressed on the Cell Membrane of T-Lymphocytes during differentiation, activation, and normal and neoplastic transformation. Their phenotypic characterization is important in Differential Di [..]

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 Tr [..]

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.

Substances elaborated by Viruses that have antigenic activity.

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 neopla [..]

Members of the integrin Family appearing late after T-Cell activation. They are a Family of Proteins initially identified at the surface of stimulated T-Cells, but now identified on a variety of Cell [..]

Antigens stimulating the formation of, or combining with Heterophile Antibodies. They are cross-reacting Antigens found in phylogenetically unrelated species.

Substances that are recognized by the immune system and induce an immune reaction.

Substances of archaeal origin that have antigenic activity.

Substances elaborated by bacteria that have antigenic activity.

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 subpopula [..]

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 an [..]

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, LEUKO [..]

An alpha-integrin subunit found on lymphocytes, granulocytes, macrophages and monocytes. It combines with the integrin beta2 subunit (CD18 ANTIGEN) to form LYMPHOCYTE FUNCTION-ASSOCIATED ANTIGEN-1.

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.

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. [..]

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-hematopo [..]

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 lipopo [..]

A cell adhesion molecule of the immunoglobulin superfamily that is expressed in ENDOTHELIAL CELLS and is involved in INTERCELLULAR JUNCTIONS.

A widely distributed cell surface transmembrane glycoprotein that stimulates the synthesis of MATRIX METALLOPROTEINASES. It is found at high levels on the surface of malignant NEOPLASMS and may play a [..]

Carbohydrate antigen which is accumulated in various human cancer tissues and secreted into the blood stream. The carbohydrate moiety can be further modified with fucose or sialic acid. Monoclonal ant [..]

A sialomucin protein that functions as a cell adhesion molecule. It is a negative regulator of certain types of HEMATOPOIETIC STEM CELLS.

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 e [..]

Differentiation antigens expressed on B-lymphocytes and B-cell precursors. They are involved in regulation of B-cell proliferation.

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, a [..]

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.

A lectin and cell adhesion molecule found in B-LYMPHOCYTES. It interacts with SIALIC ACIDS and mediates signaling from B-CELL ANTIGEN RECEPTORS.

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.

Cell-surface glycoproteins and serine protease, also known as dipeptidyl-peptidase IV, that play a role in T-lymphocyte activation. CD26 binds to adenosine deaminase on the T-cell surface. EC 3.4.14.5

A member of the tumor necrosis factor receptor superfamily found on most T-LYMPHOCYTES. Activation of T-cells by the receptor increases CD27 surface expression and T cell expansion.

T-cell differentiation antigens that serve as the receptors for the B7 antigen (ANTIGENS, CD80) which modulates T-cell lymphokine production.

Integrin beta-1 chains which are expressed as heterodimers that are noncovalently associated with specific alpha-chains of the CD49 family (CD49a-f). CD29 is expressed on resting and activated leukocy [..]

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 comp [..]

A member of the tumor necrosis factor receptor superfamily that may play a role in the regulation of NF-KAPPA B and APOPTOSIS. They normally present in a small number of cells in the LYMPH NODES and T [..]

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.

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 ce [..]

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; S [..]

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 [..]

55-kDa Glycoproteins originally defined as differentiation antigens on T-lymphocytes, but also found on other cells including monocytes/macrophages. CD4 antigens are members of the immunoglobulin supe [..]

A member of the tumor necrosis factor receptor superfamily found on mature B-LYMPHOCYTES and some EPITHELIAL CELLS, and lymphoid DENDRITIC CELLS. Evidence suggests that CD40-dependent activation of B- [..]

A sialic acid-rich protein and an integral cell membrane mucin. It plays an important role in activation of T-LYMPHOCYTES.

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 [..]

High-molecular weight glycoproteins uniquely expressed on the surface of all leukocytes and their hemopoietic progenitors. The CD45 family consists of multiple members that are all products of a singl [..]

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 medi [..]

A ubiquitously expressed membrane glycoprotein. It interacts with a variety of INTEGRINS and mediates responses to EXTRACELLULAR MATRIX PROTEINS.

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 molec [..]

Glycoproteins 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 [..]

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 a [..]

Oligosaccharide antigenic determinants found principally on NK cells and T-cells. Their role in the immune response is poorly understood.

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 enha [..]

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 mem [..]

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 ce [..]

A component of the B-cell antigen receptor that is involved in B-cell antigen receptor heavy chain transport to the PLASMA MEMBRANE. It is expressed almost exclusively in B-LYMPHOCYTES and serves as a [..]

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 [..]

The natural ligand for the T-cell antigen CD28; (ANTIGENS, CD28); mediating T- and B-cell adhesion. CD80 is expressed on activated B-cells and gamma-interferon-stimulated monocytes. The binding of CD8 [..]

A CD antigen that plays a role in T-lymphocyte proliferation and interleukin 2 production. It is a co-stimulatory ligand for the CD28 ANTIGEN on T-LYMPHOCYTES and initiates T-cell activation and immun [..]

A C-type lectin that associates with NKG2 proteins to form receptors for HLA-E antigen on NATURAL KILLER CELLS.

Differentiation antigens expressed on a variety of cell lines including myeloid and lymphoblastoid cell lines. They are members of the tumor necrosis receptor superfamily involved in the regulation of [..]

A heterodimeric protein that is a cell surface antigen associated with lymphocyte activation. The initial characterization of this protein revealed one identifiable heavy chain (ANTIGENS, CD98 HEAVY C [..]

A transmembrane glycoprotein subunit that can dimerize with a variety of light chain subunits (ANTIGENS, CD98 LIGHT CHAINS). This protein subunit serves a diverse array of functions including amino ac [..]

A family of light chains that bind to the CD98 heavy chain (ANTIGENS, CD98 HEAVY CHAIN) to form a heterodimer. They convey functional specificity to the protein.

Antigens from the house dust mites (DERMATOPHAGOIDES), mainly D. farinae and D. pteronyssinus. They are proteins, found in mite feces or mite extracts, that can cause ASTHMA and other allergic disease [..]

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 use [..]

Membrane antigens associated with maturation stages of B-lymphocytes, often expressed in tumors of B-cell origin.

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 [..]

Antigens expressed on the cell membrane of T-lymphocytes during differentiation, activation, and normal and neoplastic transformation. Their phenotypic characterization is important in differential di [..]

Substances of fungal origin that have antigenic activity.

Any part or derivative of a helminth that elicits an immune reaction. The most commonly seen helminth antigens are those of the schistosomes.

Antigens stimulating the formation of, or combining with heterophile antibodies. They are cross-reacting antigens found in phylogenetically unrelated species.

Human alloantigens expressed only on platelets, specifically on platelet membrane glycoproteins. These platelet-specific antigens are immunogenic and can result in pathological reactions to transfusio [..]

A group of lymphocyte surface antigens differentially located on subpopulations of mouse lymphocytes. This localization has been useful in distinguishing different functional subpopulations of lymphoc [..]

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.

Immunologically detectable substances found in the CELL NUCLEUS.

Substances from PLANTS that have antigenic activity.

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 [..]

Any part or derivative of any protozoan that elicits immunity; malaria (Plasmodium) and trypanosome antigens are presently the most frequently encountered.

Antigens on surfaces of cells, including infectious or foreign cells or viruses. They are usually protein-containing groups on cell membranes or walls and may be isolated.

Antigens which may directly stimulate B lymphocytes without the cooperation of T lymphocytes.

A group of differentiation surface antigens, among the first to be discovered on thymocytes and T-lymphocytes. Originally identified in the mouse, they are also found in other species including humans [..]

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.

Substances elaborated by viruses that have antigenic activity.

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 neopla [..]

foreign substances (e.g. bacteria or viruses) in the body that are capable of causing disease. The presence of antigens in the body triggers an immune response, usually the production of antibodies.

foreign substances in the body that are capable of causing disease. The presence of antigens in the body triggers an immune response, usually the production of antibodies. Antigens may be soluble subs [..]

Foreign substances (e.g. bacteria or viruses) in the body that are capable of causing disease. The presence of antigens in the body triggers an immune response, usually the production of antibodies. [ [..]

Foreign substances (e.g. bacteria or viruses) in the body that are capable of causing disease. The presence of antigens in the body triggers an immune response, usually the production of antibodies.

substances that are not supposed to be in the body, such as bacteria, viruses, toxins, or cells from other people, that stimulate the immune system to trigger an immune response

Foreign substances (e.g. bacteria or viruses) in the body that are capable of causing disease. The presence of antigens in the body triggers an immune response, usually the production of antibodies.

These are substances that are capable of inducing a specific immune response and of reacting with the products of the response such as specific antibodies or T-lymphocytes.

A foreign substance or organism that triggers an immune response and causes the body to produce antibodies.

Substances which are capable, under appropriate conditions, of inducing a specific immune response and of reacting with the products of that response, that is, with specific antibodies or specifically sensitised T-lymphocytes, or both. Antigens may be soluble substances, such as toxins and foreign proteins, or particulates, such as bacteria and tis [..]

Substances of archaeal origin that have antigenic activity. (12 Dec 1998)

Substances elaborated by bacteria that have antigenic activity. (12 Dec 1998)

<immunology> Differentiation antigens residing on human leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similiar reactivity with certain subpopulations of antigens. The subpopulations of antigens are also known by the same CD designation. (12 Dec 1998)

<immunology> 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. (12 Dec 1998)

<immunology> 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. (12 Dec 1998)

<enzyme> <immunology> Glycoproteins expressed on human granulocyte-monocyte progenitor colony forming units (cfu-gm) and their more differentiated progeny. The enzymes are also found in a large number of tissues, often associated with membranes. Registry number: EC 3.4.11.2 (12 Dec 1998)

<immunology> 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. (12 Dec 1998)

<immunology> Carbohydrate antigen which is accumulated in various human cancer tissues and secreted into the blood stream. The carbohydrate moiety can be further modified with fucose or sialic acid. Monoclonal antibodies have been determined which can discriminate each subgroup of this antigen in the sera of cancer patients. Sialyl ssea-1 ant [..]

<immunology> 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. (12 Dec 1998)

<immunology> Differentiation antigens expressed on B-lymphocytes and B-cell precursors. They are involved in regulation of B-cell proliferation. (12 Dec 1998)

<immunology> 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. (12 Dec 1998)

<immunology> Unglycosylated phosphoproteins expressed only on B-cells. They are regulators of transmembrane calcium conductance and thought to play a role in B-cell activation and proliferation. (12 Dec 1998)

<enzyme> <immunology> Cell-surface glycoproteins and serine protease, also known as dipeptidyl-peptidase IV, that play a role in t-lymphocyte activation. Cd26 binds to adenosine deaminase on the T-cell surface. Registry number: EC 3.4.14.5 (12 Dec 1998)

<immunology> Dimeric membrane glycoproteins found on most T-lymphocytes. Activation of T-cells by the antigen receptor increases CD27 surface expression. (12 Dec 1998)

<immunology> T-cell differentiation antigens that serve as the receptors for the b7 antigen (antigens, CD80) which modulates T-cell lymphokine production. (12 Dec 1998)

<immunology> Integrin beta-1 chains which are expresssed as heterodimers noncovalently associated with specific alpha-chains of the CD49 family (CD49a-f). Cd29 is expressed on resting and activated leukocytes and is a marker for total very late activation antigens on cells. (barclay et al., the leukocyte antigen factsbook, 1993, p164) (12 Dec [..]

<immunology> A 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 compl [..]

<immunology> Differentiation antigens normally present in a small number of cells in the lymph nodes and tonsils in vivo, but also capable of being induced in a wide range of cells in vitro. They are clinically useful as tumour markers for ki-1 lymphoma (lymphoma, large-cell, ki-1) and some cases of lymphomatoid papulosis, mycosis fungoides, [..]

<immunology> 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. (12 Dec 1998)

<immunology> Glycoproteins found on immature haematopoietic 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. (12 Dec 1998)

<immunology> Leukocyte differentiation antigens and major platelet membrane glycoproteins present on monocytes, endothelial cells, platelets, mammary epithelial cells, and a variety of cultured cell lines. They play major roles in adhesion phenomena, signal transduction, and haematopathology. Cd36 is also the receptor for thrombospondin and m [..]

<immunology> 55-kD glycoproteins originally defined as differentiation antigens on T-lymphocytes, but also found on other cells including monocytes/macrophages. CD4 antigens are members of the immunoglobulin supergene family and are implicated as associative recognition elements in MHC (major histocompatibility complex) class II-restricted im [..]

<immunology> Differentiation antigens found on all mature B-lymphocytes and some epithelial cells, carcinomas, and lymphoid dendritic cells. This is a member of the tumour necrosis factor superfamily. Evidence suggests that CD40-dependent activation of B-cells is important for generation of memory B-cells within the germinal centres. (12 Dec [..]

<immunology> 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 hy [..]

<immunology> High-molecular weight glycoproteins uniquely expressed on the surface of all leukocytes and their haemopoietic progenitors. The CD45 family consists of multiple members that are all products of a single gene. Cd45 expression is necessary for signalling through the T-cell receptor. (12 Dec 1998)

<immunology> 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. (12 Dec 1998)

<immunology> Glycoproteins broadly distributed among haematopoietic and non-haematopoietic cells. Cd55 prevents the assembly of c3 convertase or accelerates the disassembly of preformed convertase, thus blocking the formation of the membrane attack complex. (12 Dec 1998)

<immunology> The 140-kD 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 tumours. (12 Dec 1998)

<immunology> Oligosaccharide antigenic determinants found principally on nk cells and T-cells. Their role in the immune response is poorly understood. (12 Dec 1998)

<immunology> Glycoproteins with a wide distribution on haematopoietic and non-haematopoietic cells and strongly expressed on macrophages. Cd58 mediates cell adhesion by binding to CD2 (antigens, CD2) and this enhances antigen-specific T-cell activation. (12 Dec 1998)

<immunology> Small glycoproteins found on both haematopoietic and non-haematopoietic cells. Cd59 restricts the cytolytic activity of homologous complement by binding to c8 and c9 and blocking the assembly of the membrane attack complex. (12 Dec 1998)

<immunology> Differentiation antigens expressed on pluripotential haematopoietic 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. (12 Dec 1998)

<immunology> 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 major histocompatibility complex class I-restricted interactions. (12 Dec 1998)

<immunology> The natural ligand for the T-cell antigen CD28 (antigens, CD28) mediating t-cell and B-cell adhesion. Cd80 is expressed on activated B-cells and gamma-interferon-stimulated monocytes. The binding of CD80 to CD28 and ctla-4 provides a co-stimulatory signal to T-cells and leads to greatly upregulated lymphokine production. (12 Dec [..]

<immunology> Differentiation antigens expressed on a variety of cell lines including myeloid and lymphoblastoid cell lines. Their primary role is to regulate peripheral immune responses, which is achieved by triggering apoptosis. (12 Dec 1998)

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. (12 Dec 1998)

Membrane antigens associated with maturation stages of B-lymphocytes, often expressed in tumours of B-cell origin. (12 Dec 1998)

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 leukaemias and lymphomas. (12 Dec 1998)

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. (12 Dec 1998)

Substances of fungal origin that have antigenic activity. (12 Dec 1998)

Any part or derivative of a helminth that elicits an immune reaction. The most commonly seen helminth antigens are those of the schistosomes. (12 Dec 1998)

Antigens stimulating the formation of, or combining with heterophile antibodies. They are cross-reacting antigens found in phylogenetically unrelated species. (12 Dec 1998)

Human alloantigens expressed only on platelets, specifically on platelet membrane glycoproteins. These platelet-specific antigens are immunogenic and can result in pathological reactions to transfusion therapy. (12 Dec 1998)

A group of lymphocyte surface antigens differentially located on subpopulations of mouse lymphocytes. This localization has been useful in distinguishing different functional subpopulations of lymphocytes. For example, cytotoxic T-cells bear primarily lyt-23 on their surface and not lyt-1, whereas helper cells bear lyt-1 and not lyt-23. (12 Dec 199 [..]

Proteins, glycoprotein, or lipoprotein moieties on surfaces of tumour cells that are usually identified by monoclonal antibodies. Many of these are of either embryonic or viral origin. (12 Dec 1998)

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 t [..]

Any part or derivative of any protozoan that elicits immunity; malaria (plasmodium) and trypanosome antigens are presently the most frequently encountered. (12 Dec 1998)

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. (12 Dec 1998)

A group of differentiation surface antigens, among the first to be discovered on thymocytes and T-lymphocytes. Originally identified in the mouse, they are also found in other species including humans, and are expressed on brain neurones and other cells. (12 Dec 1998)

Antigens which may directly stimulate b lymphocytes without the cooperation of t lymphocytes. (12 Dec 1998)

Carbohydrate antigens expressed by malignant tissue. They are useful as tumour markers and are measured in the serum by means of a radioimmunoassay employing monoclonal antibodies. American spelling: antigens, tumor-associated, carbohydrate (12 Dec 1998)

Substances elaborated by viruses that have antigenic activity. (12 Dec 1998)

Those proteins recognised by antibodies from serum of animals bearing tumours induced by viruses; these proteins are presumably coded for by the nucleic acids of the same viruses that caused the neoplastic transformation. American spelling: antigens, viral, tumor (12 Dec 1998)