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Antigen 85B Mycobacterium Tuberculosis-is the most abundant protein exposed by M. Tuberculosis, as well as a potent immunoprotective antigen and a leading drug target. Ag85 induces strong T-cell proliferation and IFN-g secretion in most healthy individuals exposed to M. tuberculosis, in BCG-vaccinated mice and humans, whereas the antibody against Ag85 are more prevalent in active tuberculosis patients with decreased cellular immune response.

CST6 belongs to the type 2 cystatin family. Unlike other family members that act as active cysteine protease inhibitors, CST6 restrain the inhibition of cathepsin B but is not active against cathepsin C. CST6 are secretable proteins that influence osteogenesis and bone resorption, regulation of the hepatocyte growth factor receptors, and the response to systemic inflammation.

MMP9 is part of the matrix metalloproteinase family. MMP enzymes take part in the dismantle of extracellular matrix in different physiological pathways, for instance wound healing, bone development, reproduction etc. the enzyme is also involved in pathological pathways: metastasis, arthritis and intracerebral hemorrhage.

ANXA4 is part of the annexin family of calcium-dependent phospholipid binding proteins. ANXA4 has 45%-59% identity with other proteins of its family and shares a related size and exon-intron organization. ANXA4 interacts with ATP, and has in vitro anticoagulant activity and also inhibits phospholipase A2 activity. ANXA4 is exclusively expressed in epithelial cells. ANXA4 is a Calcium/phospholipid-binding protein which promotes membrane fusion and is involved in exocytosis.

Signal recognition particle 19kDa protein (SRP19) is a member of the SRP19 family. SRP19 binds directly to 7S RNA and mediates binding of the 54 kDa subunit of the SRP.

SRP54 is a 54-kDa subunit of the signal recognition particle (SRP), a cytoplasmic ribonucleoprotein complex which leads the translocation of newly synthesized secretory proteins from the polysome to the endoplasmic reticulum. SRP is composed of six polypeptides and a tRNA-like molecule known as 7SL RNA. SRP54 is a GTP-binding protein that directly binds the signal sequences of nascent secretory and membrane proteins. Anti-SRP autoantibodies take place in patients with an autoimmune chronic muscle inflammation called polymyositis. These auto-antibodies predominantly recognize the SRP54 subunit and in addition are able to immunoprecipitate several of the SRP subunits and the RNA component. Nearly 5% of myositis patients are positive for anti-SRP autoantibodies, increasing to 18% in the subgroup of Jo-1 autoantibody-negative patients. The classic 'anti-SRP syndrome' is a severe form of polymyositis in which the myositic inflammation is acute and aggressive onset, with common myalgias and cardiac involvement. Normally there is a poor reaction to therapy with a 5-year survival rate of about 25%.

Ornithine decarboxylase is the preliminary and rate-limiting enzyme in the biosynthetic pathway of polyamines and it takes part in the alteration of ornithine to putrescine. ODC1 is a key member of various biological processes, such as cell growth, transformation, differentiation and apoptosis. Overexpression of the ODC1 gene has a vital part in cell proliferation and the progress of cancer.

EXOSC10 is a nucleolar protein and represents one crucial component of the so-called "PM/Scl complex" or "nuclear exosome", which is an RNA-processing complex consisting of a number of exoribonucleases (not to be confused with certain multivesicular bodies which are shed by cultured cells into the culture fluid and are also called exosomes).
Autoantibodies against EXOSC10 occur in patients suffering from polymyositis, scleroderma or polymyositis/scleroderma overlap syndromes. While antibodies to other components of the exosome complex (PM/Scl 75, several Rrp proteins) can be found in some sera, practically all patients with autoantibodies against the PM/Scl complex are positive for EXOSC10 antibodies, making this specificity an important marker. The presence of EXOSC10 autoantibodies is a comparatively "good" prognostic sign in polymyositis/scleroderma overlap syndrome unlike the poor prognosis seen when other myositis and systemic sclerosis specific autoantibodies are present.

Celiac disease is an enteropathy that is characterized by intestinal lesions of variable severity. Tissue-type transglutaminase (tTG) is believed to be the predominant autoantigen for celiac disease and the corresponding autoantibodies show higher sensitivity and specificity than anti-gliadin antibodies. Highly pure recombinant human tTG is now available to replace the traditionally used tTG fraction from guinea pig.
Tissue-type transglutaminase antigens have been specifically modified for improved handling: exchange of an active site amino acid eliminates the protein cross-linking activity of the enzyme, while maintaining the native three-dimensional structure and the enzyme's secondary GTPase activity. This engineering assures reproducible properties of the antigen preparations through the absence of variable and ill-defined covalent aggregates of tTG antigen and host cell proteins.

CD74 (HLA class II histocompatibility antigen gamma chain isoform b), is a transmembrane protein (on antigen presenting cells) which is the invariant chain that chaperones MHC class IIdimers from the endoplasmic reticulum to the cell surface. CD74 is expressed by cells of both T lymphocyte and Blymphocyte lineages. CD74 upregulated in several cancers and is also expressed by non immune cells during inflammation. Diseases related with CD74 include thymic epithelial neoplasm and gastroduodenitis. Among its related super-pathways are Immune System and Immune response Antigen presentation by MHC class II. In addition CD74 functions as cell surface receptor for the cytokine MIF.

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.

Troponin is a fundamental regulatory protein of striated muscle contraction, and together with tropomyosin, is positioned on the actin filament. Troponin has 3 subunits: TnI- the inhibitor of actomyosin ATPase; TnT- contains the binding site for tropomyosin; and TnC- the protein encoded by the TNNC1 gene. The binding of calcium to TnC stops the inhibitory action of TnI, consequently allowing the interaction of actin with myosin, the hydrolysis of ATP, and the generation of tension. Mutations in the TNNC1 gene are linked to cardiomyopathy dilated type 1Z.

TSC22 domain family protein 3 (TSC22D3) protects T-cells from IL2 deprivation-induced apoptosis through the inhibition of FOXO3A transcriptional activity which initiates the down-regulation of the pro-apoptotic factor BCL2L11. In macrophages, TSC22D3 has a role in the anti-inflammatory and immunosuppressive effects of glucocorticoids and IL10. In T-cells, TSC22D3 hinders anti-CD3-induced NFKB1 nuclear translocation. In vitro, TSC22D3 curbs AP1 and NFKB1 DNA-binding activities.

Heat-stable enterotoxins (STa) are small, cysteine-rich peptides secreted by Escherichia coli that are able to induce diarrhea through the stimulation of an intestine-specific receptor-guanylyl cyclase known as STaR. Binding of STa to STaR induces a dramatic increase in the cGMP content of the cell; the increase, in turn, inhibits salt absorption and stimulates chloride secretion. This imbalance of ions is accompanied by a massive accumulation of water in the gut that gives rise to the diarrhea and dehydration characteristic of enterotoxin activity. The identification of a receptor for STa on intestinal brush border membranes suggested the existence of an endogenous activator, described guanylin, a 15-amino acid peptide purified from rat small intestine, as a potential ligand for the STaR. This peptide shares sequence similarity with STa; see also uroguanylin. The molecular cloning of the human and mouse cDNAs encoding guanylin was reported. The sequences demonstrated that guanylin is present at the C-terminal end of a larger precursor protein. Expression in mammalian cells indicated that the 94- amino acid proguanylin is inactive. The biologically active guanylin can be released by either chemical or enzymatic treatment of proguanylin. By Northern blot analysis and in situ hybridization, showed that expression of guanylin mRNA is restricted to cells of the intestinal epithelium, specifically the Paneth cells at the base of the small intestinal crypts. These results demonstrate that guanylin is an endogenous activator of STaR isolated a cDNA encoding an apparent precursor of guanylin from a human intestinal cDNA library. The mRNA was expressed at high levels in human ileum and colon. In the mouse, interspecific backcross analysis used to map the Guca2 gene to the distal half of mouse chromosome 4 in a region of homology with human chromosome 1p. By fluorescence in situ hybridization mapped the GUCA2 gene to human 1p35-p34 Guanylin is thought to modulate intestinal water/electrolyte transport in a paracrine mode reported the nucleotide sequence of the gene, the characteristics of its circulating molecular form, and its localization in enterochromaffin cells of the gut. The gene, approximately 2.6 kb in size, consists of 3 exons interrupted by 2 introns. The hormonal form of guanylin is a 94-amino acid peptide with a molecular mass of 10.3 kDa. Guanylin is synthesized by gut enterochromaffin cells as a prohormone of 115 amino acids and is processed to the molecular form of 94 amino acids circulating in the blood.

Thioredoxins are small disulphide-containing redox proteins (within the conserved Cys-Gly-Pro-Cys active site) that have been found in all the kingdoms of living organisms. Thioredoxin contains a single disulfide active site and serves as a general protein disulphide oxidoreductase. Thioredoxins are involved in the first unique step in DNA synthesis. It interacts with a broad range of proteins by a redox mechanism based on reversible oxidation of two cysteine thiol groups to a disulphide, accompanied by the transfer of two electrons and two protons. The net result is the covalent interconversion of a disulphide and a dithiol. Trx also provides control over a number of transcription factors affecting cell proliferation and death through a mechanism referred to as redox regulation. It has been suggested that thioredoxin may catalyze the formation of correct disulfides during protein folding because of its ability to act as an efficient oxidoreductant. This could be especially useful in

L-Selectin belongs to a family of divalent cation-dependent carbohydrate-binding glycoproteins or adhesion molecules. The L-Selectin molecule is composed of various domains: one homologous to lectins, one to epidermal growth factor, and two to the consensus repeat units found in C3/C4 binding proteins.
L-selectin is expressed constitutively on lymphocytes, monocytes and granulocytes and interacts specifically with carbohydrate groups on activated endothelial cells. L-Selectin may be shed by proteolytic cleavage and circulating levels in biological fluids may be used as an indicator of various pathological conditions. L-Selectin is cleaved by ADAM17.
L-selectin works as a "homing receptor" for leukocytes to enter secondary lymphoid tissues via the high endothelial venules. Ligands present on endothelial cells will attach to leukocytes expressing L-selectin, which causes the leukocytes to become localized at that juncture. The receptor is also located on the cell surfaces of "naive" T cells, which have not yet encountered their particular antigen. This surface expression is lost following the cells activation.

Vanin 1 (VNN1) belongs to the vanin family of proteins, which share extensive sequence similarity with each other, and also with biotinidase. This family includes secreted and membrane-associated proteins, a few of which have been described to participate in hematopoietic cell trafficking. No biotinidase activity has been established for any of the vanin proteins; nevertheless, they possess pantetheinase activity, which may have a role in oxidative-stress response. VNN1 protein, like its mouse homolog, is probably a GPI-anchored cell surface molecule. The mouse VNN1 protein is expressed by the perivascular thymic stromal cells and regulates migration of T-cell progenitors to the thymus. VNN1 is an amidohydrolase which hydrolyzes specifically one of the carboamide linkages in D-pantetheine thus recycling pantothenic acid (vitamin B5).

Recoverin is a member of the recoverin family of neuronal calcium sensors. Recoverin is a heterogeneously acylated calcium-binding and intracellular signal transduction 23kDa protein in the photoreceptor cells of retina. Recoverin contains four EF-hands, of which two bind Ca. Ca-induced extrusion of the acyl group from a hydrophobic cleft in the protein drives the translocation of recoverin from solution to the disc membrane. Recoverin may prolong the termination of the phototransduction cascade in the retina by blocking the phosphorylation of photo-activated rhodopsin. Recoverin plays a key role in the inhibition of rhodopsin kinase, a molecule that regulates the phosphorylation of rhodopsin. This in due course controls the ability of the eye to adapt to, and recover from, exposure to the presence of light. Recoverin is a detectable serologic protein that is expressed in patients with cancer-associated retinopathy, a paraneoplastic syndrome.

Chemokine (C-C motif) ligand 14 (CCL14) is a small cytokine belonging to the CC chemokine family. It is also commonly known as HCC-1. It is produced as a protein precursor that is procesed to generate a mature active protein containing 74 amino acids that and is 46% identical in amino acid composition to CCL3 and CCL4. This chemokine is expressed in various tissues including spleen, bone marrow, liver, muscle, and gut. CCL13 activates monocytes, but does not induce their chemotaxis. Human CCL13 is located on chromosome 17 within a cluster of other chemokines belonging to the CC family.

Chondrosarcoma Associated Gene 1 (CSAG1) belongs to a family of tumor antigens. The CSAG1 protein is expressed in chondrosarcomas, but may also be expressed in normal tissues such as testis.

Zinc-alpha-2-glycoprotein (AZGP1) protein stimulates lipid degradation in adipocytes and causes the massive fat losses linked with various advanced cancers. AZGP1 may bind polyunsaturated fatty acids.

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) induces proliferation, migration, and fenestration in capillary endothelial cells derived from endocrine glands. Its expression is induced by hypoxia and is restricted to the steroidogenic glands (ovary, testis, adrenal, and placenta). Its expression is often complementary to the expression of VEGF (MIM 192240), suggesting that these molecules function in a coordinated manner. EG-VEGF potently contracts gastrointestinal (gi) smooth muscle. Induces proliferation, migration and fenestration (the formation of membrane discontinuities) in capillary endothelial cells derived from endocrine glands. Has little or no effect on a variety of other endothelial and non-endothelial cell types.