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C-type Lectin Domain Family 1 Member B, also known as CLEC1B. NK-Natural killer cells express multiple calcium-dependent (C-type) lectin-like receptors, for instance CD94 (KLRD1; MIM 602894) and NKG2D (KLRC4; MIM 602893), which interact with major histocompatibility complex class I molecules and either inhibit or else activate cytotoxicity and cytokine secretion. CLEC1B is a C-type lectin-like receptor which is expressed in myeloid cells as well as in NK cells.

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 eosinophils by 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 ligand include CCR2, CCR3 and CCR5. The gene for human CCL11 (scya11) is encoded on three exons and is located on chromosome 17.

IL-21 is produced by CD4+ T cells in response to antigenic stimulation. Its action enhances antigen-specific responses of immune cells. The biological effects of IL-21 include induction of differentiation of T-cells-stimulated B-cells into plasma cells and memory B-cells, stimulation (in conjuction) with IL-4 of IgG production, and induction of apoptotic effects in naive B-cells and stimulated B-cells in the absence of T-cell signaling. Additionally, IL-21 promotes the anti-tumor activity of CD8+ T-cells and NK cells. IL-21 exerts its effect through binding to a specific type I cytokine receptor, IL-21R, which also contains the gamma chain (°C) found in other cytokine receptors including IL-2, IL-4, IL-7, IL-9 and IL-15. The IL-21/IL-21R interaction triggers a cascade of events which includes activation of the tyrosine kinases JAK1 and JAK3, followed by activation of the transcription factors STAT1 and STAT3.

A natural cytotoxicity receptor (NCR) NKp46 has been shown to represent a novel NK cell-specific molecule involved in human NK cell activation. The natural cytotoxicity receptors (NCRs) are a recently characterized family of Ig-like activation receptors that appear to be major triggering receptors in tumor cell recognition. The three known NCRs include NKp46 and NKp30, which are expressed on circulating NKcells, and NKp44, which is expressed only on activating NK cells. NKp46 has been implicated in NK cell-mediated lysis of several autologous tumor cells, pathogen-infected cell lines and mononuclear phagocytes infected with an intracellular bacterium. The Lysis of tumor cells by NK-cells involves recognition by NKp46 of heparan sulfate moieties of membrane heparan sulfate proteoglycans. Furthermore, NKp46 is a surface receptor involved in NK-cell cell death by apoptosis. NKp46 has two extracellular Ig-like domains followed by a ~40 residue stalk region, a type I transmembrane domain, and a short cytoplasmic tail. The extracellular Ig-like domain of NKp46 (22-255aa) is purified by FPLC gel-filtration chromatography, after refolding of the isolated inclusion bodies in a redox buffer. In addition, engagement of the antigen with the monoclonal antibody stimulates intracellular calcium levels and the synthesis of cytokines. CD59 is an NKp46 coreceptor (by physical association) together they activate cytotoxicity of human NK-cells, their engagement results in tyrosine phosphorylation of CD3-zeta chains associated with NKp46. Reduced cell surface expression of NKp46 and other NK-cell receptors is linked to the impaired NK-cell cytolytic function in viremic HIV-1 infection.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets . Its major physiologic role appears to be neutralization of molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemocinfamily. Human PF4 is used for the proof of induced thrombocytopenia. Furthermore it is used as an inhibitor in the angiogenesis during tumor therapy.

Cytotoxicity Triggering Receptor 3 also known as NCR3 is a natural cytotoxicity receptor (NCR) which assists NK cells in the lysis of tumor cells. Moreover, NCR3 interacts with CD3-zeta (CD247), a T-cell receptor. A single nucleotide polymorphism in the 5' untranslated region of NCR3 has been related with mild malaria suceptibility. Three transcript variants encoding various isoforms have been found for this gene.

The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of growth hormone (GH; MIM 139250). Early studies showed that growth hormone did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as 'somatomedin' (Daughaday et al., 1972). Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

S100A8 is a part of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a broad range of cells, and participate in the regulation of cellular processes such as cell cycle progression and differentiation. S100A8 plays a role in the inhibition of casein kinase and as a cytokine. S100A8 altered expression is related with cystic fibrosis disease. S100A8 is a calcium-binding protein that has antimicrobial activity against bacteria and fungi.S100A8 is crucial for resistance towards invasion by pathogenic bacteria. S100A8 up-regulates transcription of genes that are under the control of NF-kappa-B. S100A8 plays a role in the development of endotoxic shock in response to bacterial lipopolysaccharide. S100A8 endorses tubulin polymerization and promotes phagocyte migration and infiltration of granulocytes at sites of wounding. S100A8 takes part as a pro-inflammatory mediator in acute and chronic inflammation and up-regulates the release of IL8 and cell-surface expression of ICAM1.

IFN-alpha is produced by macrophages and has antiviral activities. Interferon stimulates the production of two enzymes: protein kinase and an oligoadenylate synthetase.

MHC Class I is a membrane spanning molecule consisting of 2 proteins. MHC Class I is just about 350 amino acids in length, with roughly 75 amino acids at the carboxylic end comprising the transmembrane and cytoplasmic portions. The remaining 270 amino acids, are divided into three globular domains labeled Alpha-1, Alpha-2 and Alpha-3 prime, with Alpha-1 being closest to the amino terminus and Alpha-3 closest to the membrane. The second portion of the molecule is a small globular protein called Beta-2 Microglobulin. It links primarily with the Alpha-3 prime domain and is essential for MHC stability.
The MHC ability to show a vast range of antigenic peptides for T cell recognition needs a compromise between broad specificity and high affinity. Both MHC class I and MHC class II show an exceptional structure while the peptide main chain is tightly bound and peptide side chains show less restrictive interactions. It is primarily the peptide side-chain contacts and conformational variability that ensures that the peptide-MHC complex presents an antigenically unique surface to T cell receptors.

ILK1 (Integrin-linked kinase) is a serine/threonine protein kinase, containing 4 ankyrin-like repeats. ILK1 regulates a number of biological properties which include: anchorage-independent cell cycle progression, tumor cell invasion and apoptosis. ILK1 can also be implicated in mediating cell architecture, adhesion to integrin substrates and anchorage-dependent growth in epithelial cells. Furthermore, ILK1 phosphorylates beta-1 and beta-3 integrin subunit on serine and threonine residues, but also AKT1 and GSK3B.
ILK1 interacts with the cytoplasmic domains of integrin ?1 and ?3 subunits in addition to several adaptors and signaling proteins, it also acts as a proximal receptor kinase regulating integrin-mediated signal transduction. ILK1 is a focal adhesion protein part of the complex ILK-PINCH. This complex is deemed to be one of the convergence points of integrin- and growth factor-signaling pathway. ILK1 is stimulated rapidly but briefly by both cell fibronectin interactions in a PI3-K-dependent manner, probably through the binding of PtdIns(3,4,5)P3 with a PH-like domain of ILK.
ILK1 over-expression has been documented in a wide variety of human malignancies.

Indoleamine 2,3-Dioxygenase 1 (IDO1) catalyzes the primary and rate-limiting stage in tryptophan catabolism to N-formyl-kynurenine. IDO1 affects on various tryptophan substrates including D-tryptophan, and serotonin and is expressed in dendritic cells, monocytes, and macrophages. IDO1 takes part in a range of pathophysiological processes like neuropathology, antimicrobial and antitumor defense, immunoregulation, and antioxidant activity. IDO1 regulates T-cell behavior by its pericellular catabolization of the necessary amino acid tryptophan.

Chemokine (C-C motif) ligand 2 (CCL2) is a small cytokine belonging to the CC chemokine family that is also known as monocyte chemotactic protein-1 (MCP-1). It is found at the site of tooth eruption and bone degradation. In the bone, CCL2 is expressed by mature osteoclasts and osteoblasts and is under the control of nuclear factor ?B (NF?B). CCL2 recruits immune cells, such as monocytes, to sites of tissue injury and infection. This chemokine is produced as a protein precursor containing signal peptide of 23 amino acids and a mature peptide of 76 amino acids. It is a monomeric polypeptide, with a molecular weight of approximately 13kDa. As with many other CC chemokines, CCL2 is located on chromosome 17 in humans. The cell surface receptors that bind CCL2 are CCR2 and CCR5.

BCA-1 is a CXC chemokine that is highly expressed in thesecondary lymphoid organs, such as follicles of the spleen, lymph nodes, and Peyer's patches. CXCL13 promotes the migration of B lymphocytes (compared to T cells and macrophages), by stimulating calcium influx into, and chemotaxis of, cells expressing Burkitt's lymphoma receptor 1 (BLR1). BCA1 therefore function in the homing of B lymphocytes to follicles. Human BCA-1 shares a 64% amino acid sequence similarity with the mouse protein and 23 - 34% amino acid sequence identity with other known CXC chemokines. Recombinant or chemically synthesized BCA1 is a potent chemoattractant for B lymphocytes but not T lymphocytes, monocytes or neutrophils. BLR1, a G protein-coupled receptor originally isolated from Burkitt’s lymphoma cells, has now been shown to be the specific receptor for BCA1. Among cells of the hematopoietic lineages, the expression of BLR-1, now designated CXCR-5, is restricted to B lymphocytes and a subpopulation of T helper memory cells.

Chemokine (C-C motif) ligand 2 (CCL2) is a small cytokine belongs to the CC chemokine family which is also known as monocyte chemotactic protein-1 (MCP-1). MCP 1 is found at the site of tooth eruption and bone degradation. In the bone, CCL2 is expressed by mature osteoclasts. CCL2 recruits immune cells, such as monocytes, to sites of tissue injury and infection. MCP 1is produced as a protein precursor containing signal peptide of 23 amino acids and a mature peptide of 76 amino acids. As with many other CC chemokines, CCL2 is located on chromosome 17 in humans. The cell surface receptors that bind CCL2 are CCR2 and CCR5.

GH is a member of the somatotropin/prolactin family of hormones which play an important role in growth control. The gene, along with four other related genes, is located at the growth hormone locus on chromosome 17 where they are interspersed in the same transcriptional orientation; an arrangement which is thought to have evolved by a series of gene duplications. The five genes share a remarkably high degree of sequence identity. Alternative splicing generates additional isoforms of each of the five growth hormones, leading to further diversity and potential for specialization. This particular family member is expressed in the pituitary but not in placental tissue as is the case for the other four genes in the growth hormone locus. Mutations in or deletions of the gene lead to growth hormone deficiency and short stature.

Isopentenyl-diphosphate Delta-isomerase 2 (IDI2) is a member of the IPP isomerase type 1 family. IDI2 catalyzes the 1,3-allylic reorganization of the homoallylic substrate isopentenyl (IPP) to its extremely electrophilic allylic isomer, dimethylallyl diphosphate (DMAPP).

SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

Macrophage Colony Stimulating Factor (M CSF) or colony stimulating factor 1, is a cytokine, that promoted differentiation in hematopoietic stem cells to macrophages. Another role of M CSF is to bind to its receptor (colony stimulating factor 1 receptor) and to take part in placenta growth and development.

IFN-Omega 1 is a type I IFN, that can be induced by virus-infected leukocytes. Type I IFN family members, which include IFN-alpha, IFN-beta, and IFN-omega, signal through IFNAR-1/IFNAR-2 receptor complex, and wield antiviral and antiproliferative activities. IFNW1 exhibits about 75% sequence homology with IFN-a, and contains 2 conserved disulfide bonds, which are essential for full biological activity.

Macrophage Inflammatory Proteins (MIP) belong to the family of chemotactic cytokines known as chemokines. In humans, there are two major forms, MIP-1a and MIP-1b that are now officially named CCL3 and CCL4 respectively. Both are major factors produced by macrophages after they are stimulated with bacterial endotoxins. They activate human granulocytes (neutrophils, eosinophilsand basophils) which can lead to acute neutrophilic inflammation. They also induce the synthesis and release of other pro-inflammatory cytokines such as interleukin 1 (IL-1), IL-6 and TNF-a from fibroblasts and macrophages. The genes for CCL3 and CCL4 are both located on human chromosome 17.

Hepatitis A Virus Cellular Receptor 2 (HAVCR2) is a member of the immunoglobulin superfamily. HACVR2 controls macrophage activation. HACVR2 inhibits T-helper type 1 lymphocyte (Th1)-mediated auto- and alloimmune responses and stimulates immunological tolerance.

Intercellular Adhesion Molecule-5 or ICAM-5 is a glycoprotein, part of the immunoglobulin family and located in the cell membrane. We can find ICAM-5 in telencephalic neurons, in a couple of adhesion activity, firstly heterophilic binding amid neurons and leukocytes and secondly, homophilic binding amid neurons. ICAM-5 is expressed exclusively in telencephalic areas of the central nervous system. Similar to other ICAMs molecules, ICAM-5 adhere to LFA-1 which is a leukocyte integrin.

Chemokine (C-C motif) ligand 8 (CCL8) is a small cytokine belonging to the CC chemokine family that was once called monocyte chemotactic protein-2 (MCP-2). The CCL8 protein is produced as a precursor containing 109 amino acids, which is cleaved to produce mature CCL8 containing 75 amino acids. The gene for CCL8 is encoded by 3 exons and is located within a large cluster of CC chemokines on chromosome 17q11.2 in humans. MCP-2 is chemotactic for and activates a many different immune cells, including mast cells, eosinophils and basophils, (that are implicated in allergic responses), and monocytes, T cells, and NK cells that are involved in the inflammatory response. CCL8 elicits its effects by binding to several different cell surface receptors called chemokine receptors. These receptors include CCR1, CCR2B and CCR5.