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TNFR binds specifically to tumor necrosis factor (TNF) and blocks its interaction with cell surface TNF receptors. TNF is a naturally occurring cytokine that is involved in normal inflammatory and immune responses. It plays an important role in the inflammatory processes of rheumatoid arthritis (RA), polyarticular-course juvenile rheumatoid arthritis (JRA), and ankylosing spondylitis and the resulting joint pathology. In addition, TNF plays a role in the inflammatory process of plaque psoriasis. Elevated levels of TNF are found in involved tissues and fluids of patients with RA, psoriatic arthritis, ankylosing spondylitis (AS), and plaque psoriasis. Two distinct receptors for TNF (TNFRs), a 55 kilodalton protein (p55) and a 75 kilodalton protein (p75), exist naturally as monomeric molecules on cell surfaces and in soluble forms. Biological activity of TNF is dependent upon binding to either cell surface TNFR. Recombinant Human TNFR is a dimeric soluble form of the p75 TNF receptor that can bind to two TNF molecules.
It inhibits the activity of TNF in vitro and has been shown to affect several animal models of inflammation, including murine collagen-induced arthritis. TNFR inhibits binding of both TNF? and TNF? (lymphotoxin alpha [LT?]) to cell surface TNFRs, rendering TNF biologically inactive. Cells expressing transmembrane TNF that bind to TNFR are not lysed in vitro in the presence or absence of complement.
TNFR can also modulate biological responses that are induced or regulated by TNF, including expression of adhesion molecules responsible for leukocyte migration (i.e., E-selectin and to a lesser extent intercellular adhesion molecule-1 [ICAM-1]), serum levels of cytokines (e.g., IL-6), and serum levels of matrix metalloproteinase-3 (MMP-3 or stromelysin).

Based on sequence similarity to VEGF-A, a gene encoding a VEGF homologue has recently been discovered in the genome of Orf virus (OV) (Lyttle et al., 1994). Different isolates of Orf virus show significant amino acid sequence similarity to VEGF-A and described as a viral virulence factor that appears to be derived from captured host genes. All eight cysteine residues of the central cysteine knot motif characteristic of members of the VEGF family are conserved among other residues in the VEGF-E proteins (Dehio et al., 1999; Wise et al., 1999). Alignment of all mammalian VEGF sequences indicated that VEGF-E is distinct from the previously described VEGFs but most closely related to VEGF-A. Like VEGF-A, VEGF-E was found to bind with high affinity to VEGF receptor-2 (KDR) resulting in receptor autophosphorylation, whilst in contrast to VEGF-A, VEGF-E can not bind to VEGF receptor-1 (Flt-1). Furthermore VEGF-E can also not bind to VEGF receptor-3 (FLT-4). Therefore VEGF-E is a potent angiog

Chemokine (C-X-C motif) ligand 10 (CXCL10) is a small cytokine belonging to the CXC chemokine family that is also known as 10 kDa IP-10. CXCL10 is secreted by several cell types in response to IFN-?. These cell types include monocytes, endothelial cells and fibroblasts. CXCL10 has been attributed to several roles, such as chemoattraction for monocytes and T cells, promotion of T cell adhesion to endothelial cells, antitumor activity, and inhibition of bone marrow colony formation and angiogenesis. The gene for CXCL10 is located on human chromosome 4 in a cluster among several other CXC chemokines. This chemokine elicits its effects by binding to the cell surface chemokine receptor CXCR3. The three-dimensional crystal structure of this chemokine has been determined under 3 different conditions to a resolution of up to 1.92A.

The secreted polypeptide noggin, encoded by the NOG gene, binds and inactivates members of the transforming growth factor-beta (TGF-beta) superfamily signaling proteins, such as bone morphogenetic protein-4 (BMP4). By diffusing through extracellular matrices more efficiently than members of the TGF-beta superfamily, noggin may have a principal role in creating morphogenic gradients. Noggin appears to have pleiotropic effect, both early in development as well as in later stages. It was originally isolated from Xenopus based on its ability to restore normal dorsal-ventral body axis in embryos that had been artificially ventralized by UV treatment. The results of the mouse knockout of noggin suggest that it is involved in numerous developmental processes, such as neural tube fusion and joint formation. Recently, several dominant human NOG mutations in unrelated families with proximal symphalangism (SYM1) and multiple synostoses syndrome (SYNS1) were identified; both SYM1 and SYNS1 have multiple joint fusion as their principal feature, and map to the same region (17q22) as NOG. All NOG mutations altered evolutionarily conserved amino acid residues. The amino acid sequence of human noggin is highly homologous to that of Xenopus, rat and mouse.

TNFR2 belongs to the TNF-receptor superfamily. TNFR2 is receptor with high affinity for TNFSF2/TNF-alpha and approximately 5-fold lower affinity for homotrimeric TNFSF1/lymphotoxin-alpha. TNFR2 mediates the majority of the metabolic effects of TNF-alpha. In addition, knockout studies in mice propose a role for TNFR2 in protecting neurons from apoptosis by stimulating antioxidative pathways. TNFR2 expression might have a significant role in the angiogenesis, tumor cell proliferation and metastasis of Invasive micropapillary carcinoma of the breast.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women. TNFR2 and TNFR1 form a heterocomplex which mediates the recruitment of 2 anti-apoptotic proteins, c-IAP1 and c-IAP2, which possess E3 ubiquitin ligase activity. IAPs’ function in TNF-receptor signaling is unknown; nevertheless, c-IAP1 is believed to potentiate TNF-induced apoptosis by the ubiquitination and degradation of TNF-receptor-associated factor 2, which mediates anti-apoptotic signals. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.

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.

CD70 also known as TNFSF7 is a cytokine which binds to CD27. TNFSF7 takes part in T-cell activation as well as induces the proliferation of costimulated T-cells. Moreover, TNFSF7 enhances the generation of cytolytic T-cells. Among the diseases which are associated with TNFSF7: Include acute myocarditis & Myocarditis.

RANKL binds to tnfrsf11b/opg and to tnfrsf11a/rank. Osteoclast differentiation and activation factor. Augments the ability of dendritic cells to stimulate naive t-cell proliferation. May be an important regulator of interactions between t-cells and dendritic cells and may play a role in the regulation of the t-cell-dependent immune response. sRANKL may also play an important role in enhanced bone-resorption in humoral hypercalcemia of malignancy. By injecting soluble RANKL, novel osteopenia model mice were established in only 50 hours. Degree of bone loss can be controlled by changing doses of sRANKL. RANKL can be used in establishing osteopenia model for in vivo screening of drugs for osteoporosis, determination of effect and mechanism, evaluation of bone anabolic drugs.

Fibroblast Growth Factors (FGFs) comprise a family of at least eighteen structurally realted proteins that are involved in a multitude of physiological and pathological cellular processes, including cell growth, differentation, angiogenesis, wound healing and tumorgenesis. The biological activities of the FGFs are mediated by a family if type I transmembrane tyrosine kinases which undergo dimerization and autophosphorylation after ligand binding. Four distinct genes encoding closely related FGF receptors, FGFR-1to -4 are known. Multiple forms of FGFR-1 to -3 are generated by alternative splicing of the mRNAs. A frequent splicing event involving FGFR-1 and -2 results in receptors containing all three Ig domains, referred to as the alpha isoform, or only IgII and IgIII, referred to as the ? isoform. Only the alpha isoform has been identified for FGFR-3 and FGFR-4. Additional splicing events for FGFR-1 to -3, involving the C-terminal half of the IgIII domain encoded by two mutually exclusive alternative exons, generate FGF receptors with alternative IgIII domains (IIIb and IIIc). A IIIa isoform which is a secreted FGF binding protein containing only the N-terminal half of the IgIII domain plus some intron sequences has also been reported for FGFR-1. Mutations in FGFR-1 to -3 have been found in patients with birth defects involving craniosynostosis.

MECR catalyzes the reduction of trans-2-enoyl-CoA to acyl-CoA with chain length from C6 to C16 in an NADPH dependent manner with preference to medium chain length substrate. MECR protein takes part in the mitochondrial synthesis of fatty acids.

RANKL binds to tnfrsf11b/opg and to tnfrsf11a/rank. Osteoclast differentiation and activation factor. augments the ability of dendritic cells to stimulate naive t-cell proliferation. May be an important regulator of interactions between t-cells and dendritic cells and may play a role in the regulation of the t-cell-dependent immune response. sRANKL may also play an important role in enhanced bone-resorption in humoral hypercalcemia of malignancy.

STIP1 is an adaptor protein that mediates the functions of HSP70 & HSP90 in protein folding. STIP1 supports the transfer of proteins from HSP70 to HSP90 by binding together HSP90 and substrate-bound HSP70. STIP1 stimulates the ATPase activity of HSP70 and inhibits the ATPase activity of HSP90, suggesting that it regulates both the conformations and ATPase cycles of these chaperones. STIP1 genetic variations are involved in regulating corticosteroid response in asthmatic subjects with reduced lung function.

VEGF-C, also known as Vascular Endothelial Growth Factor Related Protein (VRP), is a recently discovered VEGF growth factor family member that is most closely related to VEGF-D. Human VEGF-C cDNA encodes a pre-pro-protein of 416 amino acids residues. It is almost identical to the mouse VEGF-C protein. Similar to VEGF-D, VEGF-C has a VEGF homology domain spanning the middle third of the precursor molecule and long N- and C-terminal extensions. In adults, VEGF-C is highly expressed in heart, placenta, ovary and small intestine. Recombinant human VEGF-C, lacking the N- and C-terminal extensions and containing only the middle VEGF homology domain, forms primarily non-covalently linked dimers. This protein is a ligand for both VEGFR-2/KDR and VEGFR-3/FLT-4. Since VEGFR-3 is strongly expressed in lymphatic endothelial cells, it has been postulated that VEGF-C is involved in the regulation of the growth and/or differentiation of lymphatic endothelium. Although recombinant human VEGF-C is also a mitogen for vascular endothelial cells, it is much less potent than VEGF-A.

MIA2 performs as a tumour suppressor in hepatocellular carcinoma. MIA2is a novel acute phase protein which its expression is found in the liver and reacts to liver damage in chronic liver diseases and is considerably higher in severe fibrosis patients . MIA2 is induced by IL6, TGF-B & and conditioned medium from activated hepatic stellate cells. MIA2 is is mainly expressed in hepatocytes.

HEXA is the alpha subunit of the lysosomal enzyme beta-hexosaminidase which, combined with the cofactor GM2 activator protein, catalyzes the degradation of the ganglioside GM2, and other molecules having N-acetyl hexosamines terminus. The two subunits composing Beta-hexosaminidase, alpha and beta, belong to the glycosyl hydrolases family and are encoded by distinct genes. Alpha subunit gene mutations can cause Tay-Sachs disease (GM2-gangliosidosis type I).

Tumor Protein P53 Regulated Apoptosis Inducing Protein 1 (TP53AIP1) is expressed mainly in the thymus, and is localized to the mitochondrion. p53 induces TP53AIP1 production which then mediates p53- dependent apoptosis. Alternatively spliced transcript variants encoding diverse isoforms are known for TP53AIP1.

TIMP2 belongs to the TIMP gene family. The proteins encoded by this gene family are natural inhibitors of the matrix metalloproteinases, a group of peptidases that take part in degradation of the extracellular matrix. Besides having an inhibitory role against metalloproteinases, the encoded protein has a exclusive part among TIMP family members in its capability to directly suppress the proliferation of endothelial cells. Consequently, the encoded protein is crucial to the conservation of tissue homeostasis by suppressing the production of quiescent tissues as an answer to angiogenic factors, and by inhibiting protease activity in tissues undergoing renovation of the extracellular matrix.

GCK is an enzyme that expedite the formation of glucose-6-phosphate for glucose by phosphorylation. Humans and other vertebrates have GCK in the cells of the pancreas and liver. In both organs, the enzyme has an important role in carbohydrate metabolism regulation by sensing sugar levels and acting according to the change in glucose levels, that can rise after a meal or fall during fasting. Mutations in the gene that codes for this enzyme can cause hypoglycemia or diabetes.

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MYC Induced Nuclear Antigen, also known as MINA is an oxygenase which can function both as a histone lysine demethylase and a ribosomal histidine hydroxylase. MINA is involved in the demethylation of trimethylated Lys-9 on histone H3 (H3K9me3), leading to an increase in ribosomal RNA expression. MINA also catalyzes the hydroxylation of 60S ribosomal protein L27a on His-39. In addition, MINA plays a significant role in cell growth and survival. MINA is implicated in ribosome biogenesis, probably in the duration of the assembly process of pre-ribosomal particles.

The transcription of heat-shock genes is rapidly induced after temperature stress in response to environmental changes, and it is also involved in oogenesis, spermatogenesis, and placental development. Hsp90, is a major repressor of HSF1 gene. HSF1 is known for its participation in heat shock response. HSF1 protein regulates the transcription of hundreds of targets, such as genes involved in protein folding, detoxification, energy generation, carbohydrate metabolism, and cell wall organization. HSF1 binds to MTA1 in vitro & in breast carcinoma. Suppression of estrogen-dependent transcription may contribute to role of HSF1 in cancer. Human cancer lines of diverse origins express higher dependence on HSF1 function to maintain proliferation and survival than their non-transformed counterparts. HSF1 induces anticoagulation and relaxation factors in vascular endothelial cells and could therefore be used to treat cardiovascular disease. HSF1 is directly involved in the regulation of HO1 havi

IFN-gamma produced by lymphocytes activated by specific antigens or mitogens.
IFN-gamma, in addition to having antiviral activity, has important immunoregulatory functions, it is a potent activator of macrophages, and has antiproliferative effects on transformed cells and it can potentiate the antiviral and antitumor effects of the type I IFNs.

GDF15 is part of the TGF-Beta superfamily that is involved in regulating inflammatory and apoptotic pathways in injured tissues and throughout disease processes. GDF15 is most abundant in the liver. Its expression in liver can be considerably up-regulated in during injury of organs such as liver, kidney, heart and lung. GDF-15 promotes proliferation or growth arrest and differentiation due to differences in cellular differentiation. GDF15 prevents apoptosis in cerebellar granule neurons by activating Akt and inhibiting endogenously active ERK. GDF15 is a novel autocrine/endocrine factor that antagonizes the hypertrophic response and loss of ventricular performance.

Glia Maturation Factor-Beta (GMF-Beta) is a 17 kDa protein nerve gorwth factor identified as a growth and differentiation factor in the vertebrate brain.

Glia Maturation Factor-Beta stimulates differentiation of normal neurons as well as glial cells. GMFB inhibits the proliferation of the N-18 neuroblastoma line and the C6 glioma line while promoting their phenotypic expression.
GMF-beta inhances the phenotypic expression of glia & neurons thus inhibits the proliferation of their respective tumors when added to cell culture. Although astrocytes produce GMF-b and stores it inside the cells, they don’t secrete the GMF-B into the cultured medium. Cell- surface GMFb acts on the target cells at close range when cells are in direct contact. GMF-Beta is produced by thymic epithelial cells and plays an important role in T cell development in favor of CD4+ T cells.
GMF-Beta is a brain-specific protein which belongs to the actin-binding proteins (ADF) family. GMF-beta appears to play a role in the differentiation, maintenance, and regeneration of the nervous system. It also supports the progression of certain auto-immune diseases, possibly through its ability to induce the production and secretion of various pro-inflammatory cytokines.

NFATC2, also known as nuclear factor of activated T-cells 2, belongs to the nuclear factor of activated T cells family. NFATC2 takes a significant part in the course of T helper cell differentiation, activation, and effector function. Even though KO of an individual NFAT isoform in T cells directs to rather minor effects, T cells lacking for NFATC1 and 2 totally fail to produce T helper cell effector cytokines, for instance the interleukins IL-4 and IL-2. Moreover, NFATC2 is highly phosphorylated and kept in the cytoplasm. Next T cell receptor stimulation, dephosphorylation via calcium-activated calcineurin induces a conformational modification of NFATC2 which reveals a few nuclear localization sequences.