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CD68 encodes a 110-kD transmembrane glycoprotein that is highly expressed by human monocytes and tissue macrophages. It is a member of the lysosomal/endosomal-associated membrane glycoprotein (LAMP) family. The protein primarily localizes to lysosomes and endosomes with a smaller fraction circulating to the cell surface. It is a type I integral membrane protein with a heavily glycosylated extracellular domain and binds to tissue- and organ-specific lectins or selectins. The protein is also a member of the scavenger receptor family. Scavenger receptors typically function to clear cellular debris, promote phagocytosis, and mediate the recruitment and activation of macrophages. Alternative splicing results in multiple transcripts encoding different isoforms.

CD27 belongs to the TNF-receptor superfamily. CD27 is necessary for initiation and long-term maintenance of T cell immunity. CD27 binds to ligand CD70, and has a crucial role in regulating B-cell activation and immunoglobulin synthesis. The CD27 receptor transduces signals which result in the activation of NF-kappaB and MAPK8/JNK. Adaptor proteins TRAF2 and TRAF5 mediate the signaling process of CD27. CD27-binding protein (SIVA), which is a proapoptotic protein, can bind to the CD27 receptor and is believed to have a significant role in the apoptosis induced by CD27.

CD207 (C-type lectin domain family 4 member K) is expressed in Langerhans cells which are immature dendritic cells of the epidermis and mucosa. Moreover, CD207 is expressed in several other dendritic cell types including dermal CD103+ DCs and splenic CD8+ DCs. Langerin is localized in the Birbeck granules, the organelles present in the cytoplasm of Langerhans cells and comprised of superimposed and zippered membranes. CD207 is a C-type lectin with mannose binding specificity, and it has been suggested that mannose binding by the CD207 protein leads to internalization of antigen into Birbeck granules thus providing access to a nonclassical antigen-processing pathway.

CD47, functions in cell adhesions by performing as an adhesion receptor for THBS1 on platelets, furthermore CD47 plays a role in the modulation of integrins. In addition, CD47 takes a vital part in memory formation as well as synaptic plasticity in the hippocampus. Receptor for SIRPA avoids maturation of immature dendritic cells and inhibits cytokine production by mature dendritic cells. CD47 prevents premature elimination of red blood cells, and it is also implicated in membrane permeability changes induced following virus infection.

CD274 takes part in the costimulatory signal, vital for T-cell proliferation and creation of IL10 and IFNG, in a PDCD1-independent and an IL2-dependent manner. CD274 collaboration with PDCD1 inhibits cytokine production and T-cell proliferation.

CD14 (also known lipopolysaccharide (LPS) receptor) is expressed strongly on monocytes and macrophage and weakly on the surface of neutrophils. CD14 is anchored to cells by linkage to glycosylphosphatidylinositol (GPI) and functions as a high affinity receptor for complexes of LPS and LPS binding protein (LBP). Soluble CD14, also binding to LPS, acts at physiological concentration as an LPS agonist and has, at higher concentrations, an LPS antagonizing effect in cell activation. CD14 has been shown to bind apoptotic cells.

CD33 is putative adhesion molecule of myelomonocytic-derived cells which mediates sialic-acid dependent binding to cells. CD33 prefers to bind to alpha-2,6-linked sialic acid. The sialic acid recognition site is masked by cis interactions with sialic acids on the same cell surface. In the immune response, CD33 perform as an inhibitory receptor upon ligand induced tyrosine phosphorylation by recruiting cytoplasmic phosphatases through their SH2 domains which block signal transduction through dephosphorylation of signaling molecules. In addition, CD33 induces apoptosis in acute myeloid leukemia.

CD27 belongs to the TNF-receptor superfamily. CD27 is necessary for initiation and long-term maintenance of T cell immunity. CD27 binds to ligand CD70, and has a crucial role in regulating B-cell activation and immunoglobulin synthesis. The CD27 receptor transduces signals which result in the activation of NF-kappaB and MAPK8/JNK. Adaptor proteins TRAF2 and TRAF5 mediate the signaling process of CD27. CD27-binding protein (SIVA), which is a proapoptotic protein, can bind to the CD27 receptor and is believed to have a significant role in the apoptosis induced by CD27.

CD14 (also known lipopolysaccharide (LPS) receptor) is expressed strongly on monocytes and macrophage and weakly on the surface of neutrophils. CD14 is anchored to cells by linkage to glycosylphosphatidylinositol (GPI) and functions as a high affinity receptor for complexes of LPS and LPS binding protein (LBP). Soluble CD14, also binding to LPS, acts at physiological concentration as an LPS agonist and has, at higher concentrations, an LPS antagonizing effect in cell activation. CD14 has been shown to bind apoptotic cells.

CD1B belongs to CD1 family of transmembrane glycoproteins, which are structurally associated with the MHC proteins and form heterodimers with the beta-2-microglobulin. CD1B includes one Ig-like domain. CD1B is an antigen-presenting protein which connects self and nonself lipid and glycolipid antigens and displays them to T-cell receptors on natural killer T-cells.

CD164, also known as Multi-Glycosylated Core Protein 24 is amember of the CD164 family.

CD79B is a 36 kDa trans membrane glycoprotein belonging to the immunoglobulin superfamily. Heterodimers of CD79A and CD79B connect with a membrane attached immunoglobulin on the B cell surface to create the B cell antigen receptor complex (BCR). CD79A and CD79B are essential for BCR-mediated signaling and subsequently for the development and activation of B lineage cells.

CD200 is a type-1 membrane glycoprotein which is a part of the immunoglobulin superfamily due to its 2 immunoglobulin domains. CD200 regulates myeloid cell activity and delivers an inhibitory signal for the macrophage lineage in various tissues. CD200 is also Costimulates T-cell proliferation.

CD14 (also known lipopolysaccharide (LPS) receptor) is expressed strongly on monocytes and macrophage and weakly on the surface of neutrophils. CD14 is anchored to cells by linkage to glycosylphosphatidylinositol (GPI) and functions as a high affinity receptor for complexes of LPS and LPS binding protein (LBP). Soluble CD14, also binding to LPS, acts at physiological concentration as an LPS agonist and has, at higher concentrations, an LPS antagonizing effect in cell activation. CD14 has been shown to bind apoptotic cells.

CD79B is a 36 kDa trans membrane glycoprotein belonging to the immunoglobulin superfamily. Heterodimers of CD79A and CD79B connect with a membrane attached immunoglobulin on the B cell surface to create the B cell antigen receptor complex (BCR). CD79A and CD79B are essential for BCR-mediated signaling and subsequently for the development and activation of B lineage cells.

CD274 takes part in the costimulatory signal, vital for T-cell proliferation and creation of IL10 and IFNG, in a PDCD1-independent and an IL2-dependent manner. CD274 collaboration with PDCD1 inhibits cytokine production and T-cell proliferation.

Low affinity immunoglobulin gamma Fc region receptor III-A (FCGR3A) is a receptor for the Fc portion of immunoglobulin G, and is involved in the elimination of antigen-antibody complexes from the circulation, as well as other antibody-dependent responses. FCGR3A needs to associate with the gamma subunit of Fc epsilon. The FCGR3A receptor is expressed on natural killer (NK) cells as an integral membrane glycoprotein anchored through a transmembrane peptide, while FCGR3B is expressed on polymorphonuclear neutrophils (PMN) where the receptor is anchored through a phosphatidylinositol (PI) linkage. In addition, FCGR3A is expressed on macrophages, subpopulation of T-cells, immature thymocytes and placental trophoblasts. FCGR3A mediates antibody-dependent cellular cytotoxicity (ADCC) and other antibody-dependent responses, such as phagocytosis. FCGR3A gene mutations are linked with susceptibility to recurrent viral infections, susceptibility to systemic lupus erythematosus, and alloimmune neonatal neutropenia.

FCER2, or Fc epsilon RII, is a receptor for IgE with low affinity, which is critical to regulation of IgE levels. IgE is an antibody isotype that attached to allergy and resistance to parasites. FCER2 is a C-type lectin, contrary to many of the receptors for antibodies. FCER2 is located on activated macrophages, mature B cells, follicular dendritic cells, platelets and eosinophils.

CD40L or CD154 is a membrane glycoprotein and differentiation antigen expressed on the surface of T-cells. The CD40 ligand stimulates B-cell proliferation and secretion of all immunoglobulin isotypes in the presence of cytokines . CD40 ligand has been shown to induce cytokine production and tumoricidal activity in peripheral blood monocytes. It also costimulates proliferation of activated T-cells and this is accompanied by the production of IFN-gamma , TNF-alpha , and IL2 .

CD3-gamma polypeptide is encoded by CD3 Gamma (CD3G) which together with CD3-epsilon, -delta and -zeta, and the T-cell receptor alpha/beta and gamma/delta heterodimers, configures the T-cell receptor-CD3 complex. The T-cell receptor-CD3 complex takes part in coupling antigen recognition to numerous intracellular signal-transduction pathways. The genes encoding the epsilon, gamma and delta polypeptides are located in the same cluster on chromosome 11. Deficiencies in this gene are associated with T cell immunodeficiency.

CD8B encodes the CD8 beta chain isoforms of the CD8 antigen. CD8 is a cell surface glycoprotein which facilitates efficient cell-cell interactions within the immune system and is located on most cytotoxic T lymphocytes. The T-cell receptor on the T lymphocyte and the co-receptor CD8 antigen identify antigens exposed by an antigen presenting cell (APC) in the context of class I MHC molecules. The functional co-receptor is either a heterodimer composed of one alpha and one beta chain or a homodimer composed of two alpha chains. Both alpha and beta chains share substantial homology to immunoglobulin variable light chains.

FCGR3B, also known as CD16b belongs to the Ig super family. FCGR3B encodes a glycosylphosphatidylinositol (GPI)-anchored protein which is expressed constitutively by neutrophils. FCGR3B binds to complex or aggregated IgG and monomeric IgG. Different from III-A, FCGR3B cannot arbitrate antibody-dependent cytotoxicity and phagocytosis. FCGR3B operate to capture immune complexes in peripheral blood circulation that does not activate neutrophils.

Membrane cofactor protein isoform 14 (CD46), is a type I membrane protein which has cofactor activity for inactivation of complement components C3b and C4b by serum factor I. This function resides in the complement control protein repeats (CCPs), with CCP1–4 vital for regulation. CD46 is also involved in the fusion of the spermatozoa with the oocyte during fertilization. CD46 is common in thymocytes, T cells, B cells, monocytes, granulocytes, NK cells, platelets, endothelial cells, epithelial cells, fibroblasts, placenta and sperm.

CD84 belongs to the signaling lymphocyte activation molecule (SLAM) family which forms a subset of the greater CD2 cell-surface receptor Ig superfamily. CD84, a membrane glycoprotein, is a homophilic adhesion molecule found in various immune cells types and takes part in regulating receptor-mediated signaling in those cells.