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CD40 is part of the TNF-receptor superfamily. CD40 is a necessary mediator for vast range of immune and inflammatory responses together with T cell-dependent immunoglobulin class switching, memory B cell growth, and germinal center formation. The transcription factor AKNA regulates the expression of CD40 and its ligand, which is vital for homotypic cell interactions. Adaptor protein TNFR2 interacts with CD40 and serves as a mediator of the signal transduction. The interaction of CD40 and its ligand is crucial for amyloid-beta-induced microglial activation, and thus is thought to be an early event in Alzheimer disease pathogenesis. CD40 is the receptor for TNFSF5/CD40L.

Factor IX is a glycoprotein, which is synthesized in the liver. The domain structure of factor IX is similar to that of the other vitamin K dependent coagulation factors. The NH2-terminal region contains 12 g-carboxyglutamic acid (gla) residues, which facilitate the calcium dependent binding of factor IX to negatively charged phospholipid surfaces. Two domains which are homologous to epidermal growth factor (EGF) span the region between the NH2-terminal gla domain and the activation peptide (Ala-146 to Arg-180). Factor IX is activated by either factor XIa or the factor VIIa/tissue factor/phospholipid complex. Cleavage at site A yields the intermediate IXa, which is subsequently converted to the fully active form IXab by cleavage at site B. The NH2-terminal light chain (GLA and EGF domains) remains covalently attached to the COOH-terminal heavy chain by a disulfide bond. The serine protease catalytic triad (Ser-365, His 221, Asp-269) is located in the heavy chain. Factor IXab is the catalytic component of the “intrinsic factor Xase complex” (factor VIIIa/IXa/Ca2+/phospholipid) which proteolytically activates factor X to factor Xa.

Lipocalin-2 also called Neutrophil Gelatinase Associated Lipocalin (NGAL) belongs to a family of lipocans which include 25 proteins (including a1-microglobulin and b-lactoglobulin), which are characterized by their ability to bind small lipophilic substances in their hydrophobic core.
They thereby serve as transporters of substances like retinal, biliverdins & prostaglandins. There are indications that NGAL is involved in modulation of the inflammatory response and is found in the plasma of patients after stroke.

HBsAg is the surface antigen of the Hepatitis-B-Virus (HBV) S-gene. The capsid of a virus has different surface proteins from the rest of the virus. The antigen is a protein that binds specifically on one of these surface proteins. It is commonly referred to as the Australian Antigen.

MHC Class II is consists of 2 membrane spanning proteins. Each of these proteins is roughly 30 kDa, and has of two Globular domains, Alpha-1, Alpha-2, Beta-1 and Beta-2. The two regions farthest away from the membrane are alpha-1 and beta-1. The two proteins link without Covalent Bonds. The MHC Class II protein mainly presents peptides, which have been digested from external sources. MHC Class II is normally only expressed by Antigen Presenting Cells (APC) which digest foreign protein. Within the RER the alpha and beta proteins of the molecule, associate with each other, while a third protein called the "invariant chain," is necessary for stabilizing the complex, without it, they will not associate. The MHC-invariant complex is then passed from the RER, into and out of, the Golgi body. It fuses with an Endocytic compartment, where an external protein has been sampled and degraded.

Chemokine (C-C motif) ligand 11 (CCL11) is a small cytokine belonging to the CC chemokine family that is also known as eotaxin. CCL11 selectively recruits eosinophilsby inducing their chemotaxis, and therefore, is implicated in allergic responses. The effects of CCL11 are mediated by its binding to a G-protein-linked receptor known as a chemokine receptor. Chemokine receptors for which CCL11 is a ligandinclude CCR2, CCR3and CCR5. The gene for human CCL11 (scya11) is encoded on three exons and is located on chromosome 17.

CD3 has four peptide chains (gamma, delta, epsilon and zeta) that form CD3. Defects in CD3 are associated with T cell immunodeficiency CD3 complex mediates signal transduction.

CD4 is a cell-surface glycoprotein found on the mature helper T cells and immature thymocytes, as well as on monocytes and macrophages. (Some cytotoxic T cells have CD4 protein as well.) Normally, about 65% of T cells in the blood are CD4+ (have CD4 protein protruding from their membrane). A mature T cell with either have CD4 or CD8, but not both. During one stage of development T cells develop CD4 and CD8 receptors, but they eventually are differentiated in the thymus and become more specialized.

IL4 is a pleiotropic cytokine produced by activated T cells. IL4 is a ligand for interleukin 4 receptor. The interleukin 4 receptor also binds to IL13, which contributes to various overlapping roles of this cytokine and IL13. STAT6, a signal transducer and activator of transcription plays a main role in mediating the immune regulatory signal of this cytokine. IL4, IL3, IL5, IL13, and CSF2 form a cytokine gene cluster on chromosome 5q, with this gene particularly close to IL13. IL4, IL13 and IL5 are regulated co-ordinately by several long-range regulatory elements in an over 120 kilobase range on the chromosome.

CFLAR contains two death effector domains (DEDs) and a caspase-like domain. CFLAR may play a critical role between cell survival and cell death pathway in mammalian cells. CFLAR also interacts with adapter protein FADD and caspase-8 and -10, and potently inhibits apoptosis induced by all known death receptors DR3 (death receptor 3), TRAIL-R (TNF-related apoptosis-inducing ligand receptor) and TNFR1 (tumor necrosis factor receptor 1).

The B7 proteins are crucial in the regulation of the adaptive immune system. Among them is NCR3LG1. NCR3LG1 is part of the B7 family and is expressed on tumor cells. NCR3LG1 Interaction with NKp30 protein results in cytotoxicity and natural killer cell activation.Humans and rats have a single NCR3LG1 gene; though, numerous B7H6 genes were detected in a single large cluster in the Xenopus genome. NCR3LG1, a ligand for the NK cell activating receptor NKp30, targest to produce CAR that targets multiple tumor types. NCR3LG1 is expressed on many primary human tumors, including leukemia, lymphoma and gastrointestinal stromal tumors, though it is not constitutively expressed on normal tissues.

CTLA-4 is a member of the immunoglobulin superfamily and encodes a protein which transmits an inhibitory signal to T cells. The protein contains a V domain, a transmembrane domain, and a cytoplasmic tail. Alternate transcriptional splice variants, encoding different isoforms, have been characterized. The membrane-bound isoform functions as a homodimer interconnected by a disulfide bond, while the soluble isoform functions as a monomer. Mutations in this gene have been associated with insulin-dependent diabetes mellitus, Graves disease, Hashimoto thyroiditis, celiac disease, systemic lupus erythematosus, thyroid-associated orbitopathy, and other autoimmune diseases.

CD8 is a cell surface glycoprotein found on most cytotoxic T lymphocytes that mediates efficient cell-cell interactions within the immune system. CD8 acts as a co-receptor, and the T-cell receptor on the T lymphocyte recognize antigen displayed by an antigen presenting cell (APC) in the context of class I MHC molecules. The functional CD8 is either a homodimer composed of two alpha chains, or a heterodimer composed of one alpha and one beta chain. Both alpha and beta chains share significant homology to immunoglobulin variable light chains.
CD8 identifies cytotoxic/suppressor t-cells that interact with MHC class I bearing targets. CD8 is thought to play a role in the process of t-cell mediated killing. CD8 alpha chains bind to class-I MHC molecules alpha-3 domains.

Leukocyte Cell Derived Chemotaxin 1 (214-333 a.a.), also known as LECT1, is a glycosylated transmembrane protein which is cleaved to form a mature, secreted protein. The mature protein encourages chondrocyte growth and inhibits angiogenesis. The mature protein takes part in endochondral bone development by permitting cartilaginous anlagen to be vascularized and replaced by bone. LECT1 is expressed in the avascular area of prehypertrophic cartilage and its expression reduces during vascular invasion and chondrocyte hypertrophy.

MHC Class II is consists of 2 membrane spanning proteins. Each of these proteins is roughly 30 kDa, and has of two Globular domains, Alpha-1, Alpha-2, Beta-1 and Beta-2. The two regions farthest away from the membrane are alpha-1 and beta-1. The two proteins link without Covalent Bonds. The MHC Class II protein mainly presents peptides, which have been digested from external sources. MHC Class II is normally only expressed by Antigen Presenting Cells (APC) which digest foreign protein. Within the RER the alpha and beta proteins of the molecule, associate with each other, while a third protein called the "invariant chain," is necessary for stabilizing the complex, without it, they will not associate. The MHC-invariant complex is then passed from the RER, into and out of, the Golgi body. It fuses with an Endocytic compartment, where an external protein has been sampled and degraded.

CCL23 (MIP-3) is a ligand for the CCR1chemokine receptor. CCL23 is one of several cytokine genes clustered on the q-arm of chromosome 17, in a locus containing several other CC chemokines. MIP-3 chemoattracts monocytes, resting T-lymphocytes and neutrophils, but not activated lymphocytes. Furthermore, it was shown that MIP-3 inhibits colony formation of bone marrow myeloid immature progenitors. MIP-3 is mainly expressed in lung and liver tissue, but can be also found in bone marrow and placenta, as well as in some cell lines of myeloid origin.
Alternative splicing of the CCL23 gene produces 2 mRNAs which encode a short (CK?8) and a long (CK?81) isoform of the MIP-3. CK?8 cDNA encodes a 120 amino acid residue precursor protein with a putative 21 a.a. residue signal peptide which is cleaved to generate a 99 a.a. residue mature CK?8 (a.a. 22-120). Further N-terminal processing of the 99 a.a. residue variant can produce a 75 a.a. residue CK?8 (a.a. 46-120) which is considerably more active than the 99 a.a. residue variant.
MIP-3 may be involved in the malignant progression of certain human cancer cells which overexpress ErbB2 through the transactivation of ErbB2 tyrosine kinase. MIP-3 may also be involved in angiogenesis via upregulation of matrix metalloproteinase MMP-2 expression.

Eotaxin-2, also called MPIF2 & Ck?6, is a novel CC chemokine produced by activated monocytes and T lymphocytes. Eotaxin-2 selectively chemoattracts cells expressing CCR3 including eosinophils, basophils, Th2 T cells, mast cells, and certain subsets of dendritic cells. Furthermore, Eotaxin-2 inhibits the proliferation of multipotential hematopoietic progenitor cells. The mature protein, which includes C-terminal truncation, contains 78 amino acids (92 amino acids for the mouse homolog, without C-terminal truncation).
CCL24 functions as a chemotactic chemokine for resting t-lymphocytes, and eosinophils. CCL24 has lower chemotactic activity for neutrophils but none for monocytes and activated lymphocytes. CCL24 is a strong suppressor of colony formation by a multipotential hematopoietic progenitor cell line and binds to CCR3.

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.

CD31 is a glycoprotein expressed on endothelial cells, platelets, macrophages and Kupffer cells, granulocytes, T / NK cells, lymphocytes, megakaryocytes, fibroblasts, osteoclasts, neutrophils. In humans, the gene encoding CD31 is found on chromosome 17.
CD31 is a cluster of differentiation molecule. It is also called PECAM-1 for platelet endothelial cell adhesion molecule. It plays a key role in removing aged neutrophils from the body. Both the neutrophil and the macrophage express CD31 on their membranes, and during the testing process, these CD31 molecules bind the two cells together. If the neutrophil is healthy, it will send a signal to the macrophage, and the CD31 molecules will detach.
CD31 is also expressed in certain tumors, including epithelioid hemangioendothelioma, epithelioid sarcoma-like hemangioendothelioma, other vascular tumors, histiocytic malignancies, and plasmacytomas. It is rarely found in some sarcomas and carcinomas.

CD44 is a cell-surface glycoprotein that plays a role in cell-cell interactions, cell adhesion and migration. CD44 is a receptor for hyaluronic acid and also interacts with other ligands, such as osteopontin, collagens, and matrix metalloproteinases. CD44 participates in a wide variety of cellular functions such as lymphocyte activation, recirculation and homing, hematopoiesis, and tumor metastasis.
CD44 and CD49d are putative activity markers and CD44 a potential novel therapeutic target in multiple sclerosis. Increased CD44 antigen is associated with relapses in non-small cell lung cancers.

CD57 also called B3GAT1is part of the glucuronyltransferase gene family. CD57 exhibits strict acceptor specificity, recognizing nonreducing terminal sugars and their anomeric linkages. CD57 takes part in the glucuronyl transfer reaction during the biosynthesis of the carbohydrate epitope HNK-1.