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Mycobacterium antigen ESAT-6 has been isolated from low molecular weight fractions of the shot-term-culture filtrate (ST-CF) and it can easily be detected in tuberculosis patients.
The export of ESAT-6 which is a potent T-cell antigen, and related proteins requires a dedicated secretory apparatus that is encoded by a group of genes, several of which also code for proteins that are recognized strongly by T cells. The ESAT-6 systems can consequently be considered as immunogenicity islands and there is mounting evidence that the equivalent genes are subject to selective pressure imposed by the immune system of the host.
This antigen includes many epitopes detectable in the serum of most patients with tuberculosis (more than 90%). By the attempts to obtain the vaccine on the basis of ESAT-6 it was demonstrated that the optimization of adjuvant is very important when using the combination of dioctadecylammonium bromide and monophosphoryllipide.
Recently it was shown that ESAT-6 is very potential as diagnostic for differentiation between the mycobacterial infection and BCG vaccination. The main topic in ESAT-6 using is in antibody production and in test-systems for tuberculosis elaboration.

Meteorin (METRN) is involved in both glial cell differentiation and axonal network formation during neurogenesis. METRN promotes astrocyte differentiation and transforms cerebellar astrocytes into radial glia. Moreover, the METRN protein stimulates axonal extension in small and intermediate neurons of sensory ganglia by activating nearby satellite glia.

Elongin B (Elob) is a subunit of the transcription factor B (SIII) complex. SIII complex is a general transcription elongation factor that increases the RNA polymerase II transcription elongation past template-encoded arresting sites. The SIII complex comprised of a transcriptionally active subunit (A) and 2 regulatory subunits (B and C). Subunit A is transcriptionally active and its transcription activity is enhanced by binding to the dimeric complex of the SIII regulatory subunits B and C. The von Hippel-Lindau tumor suppressor protein binds to elongin B and C and inhibits transcription elongation.

Myozenin 1 (MYOZ1) is a member of the myozenin family. MYOZ1 is mostly expressed in the skeletal muscle. Members of the myozenin family act as calcineurin-interacting proteins which helps tether calcineurin to the sarcomere of cardiac and skeletal muscle. The myozenin family plays a significant role in modulation of calcineurin signaling.

TMEFF1 is a type I transmembrane glycoprotein which includes 2 follistatin modules and an EGF domain in its extracellular domain, a transmembrane domain and a short cytoplasmic tail. The extracellular domain of TMEFF1 can be released as a soluble protein. TMEFF1 is primarily expressed in brain, but is downregulated in brain neoplasms. TMEFF1 selectively regulates nodal but not activin signaling through direct binding to the nodal co-receptor, Cripto. TMEFF inhibits NODAL and BMP signaling through neural patterning and also a possible tumor suppressor in brain cancers.

Serpin Peptidase Inhibitor, Clade C Member 1 (SERPINC1), which is a part of the serpin superfamily, is a plasma protease inhibitor. SERPINC1 inhibits thrombin and other activated serine proteases of the coagulation system, and regulates the blood coagulation cascade. SERPINC1 also inhibits Thrombin and Factors IXa, Xa and XIa. Deficiencies in SERPINC1 can cause ATIII deficiency, an autosomal dominant disease which might lead to a hereditary thrombophilia.

Epiregulin is part of the EGF family. Epiregulin functions as a ligand of EGFR, as well as a ligand of most members of the ERBB (v-erb-b2 oncogene homolog) family of tyrosine-kinase receptors.Epiregulin is expressed mostly in the placenta and peripheral blood leukocytes and in specific carcinomas of the bladder, lung, kidney and colon. Epiregulin stimulates the proliferation of keratinocytes, hepatocytes, fibroblasts and vascular smooth muscle cells. Epiregulin inhibits the growth of several tumor-derived epithelial cell lines. Human Epiregulin is initially synthesized as a glycosylated 19.0 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a 6.0 kDa mature secreted sequence.

Sialic Acid Binding Ig Like Lectin 5, also known as SIGLEC5 is a member of the immunoglobulin superfamily and SIGLEC family. SIGLEC5 contains of 2 Ig-like C2-type domains and 1 Ig-like V-type domain. In addition, SIGLEC5 is expressed by monocytic/myeloid lineage cells. SIGLEC5 is expressed at high levels in peripheral blood leukocytes, spleen, and at lower levels in lymph node, appendix, pancreas, lung, and thymus.

DiGeorge syndrome critical region 6-like protein (DGCR6L) shares homology with the Drosophila gonadal protein, it is expressed in gonadal tissues and germ cells, and with the human laminin gamma-1 chain which functions in cell attachment and migration. DGCR6L is located in a region of chromosome 22 involved in the DiGeorge syndrome, one aspect of a wider collection of anomalies referred to as the CATCH 22 syndrome. Moreover, it is one of two functional genes encoding nearly identical proteins which have analogous expression patterns.

Tubby-related protein 1 (TULP1) belongs to the TULP family of 4 proteins (TUB and TULP1, -2, and -3), categorized structurally by the highly conserved C-terminal half of the protein. Tubby-like gene family (TULPs) members are found in plants, vertebrates, and invertebrates and encode proteins of unknown function. TULP proteins share a conserved C-terminal region of roughly 200 amino acid residues. In the retina, TULP1 is observed exclusively in the photoreceptor cells, localizing predominantly in the inner segments and connecting cilium and to a lesser degree in the perinuclear cytoplasm and synaptic termini. TULP1 gene mutations are linked with retinitis pigmentosa.

Listeriolysin O (aka LLO) is a hemolysin produced by Listeria monocytogenes bacteria, the pathogen responsible for causing listeriosis. The toxin may be regarded as a virulence factor, since it is crucial for the virulence of L. monocytogenes. LLO is a single polypeptide protein encoded by the hlyA gene and composed of 529 residues. LLO is a thiol-activated cholesterol-dependent pore forming toxin protein; therefore, it is activated by reducing agents and inhibited by oxidizing agents. Still, LLO differs from other thiol-activated toxins, as its cytolytic activity is maximized at a pH of 5.5. Inside the acidic phagosomes (average pH ~ 5.9) of cells that have phagocytosed L. monocytogenes, LLO is selectively activated by maximizing activity at a pH of 5.5. Following the phagosome lysis by LLO, the bacterium breaks out into the cytosol, where it is able to grow intracellularly, and the toxin has reduced activity in the more basic cytosol. Thus, LLO permits L. monocytogenes to break out from the phagosomes into the cytosol without harming the plasma membrane of the infected cell, which allows the bacteria to live intracellularly, where they are sheltered from extracellular immune system factors such as the complement system and antibodies. LLO also brings about dephosphorylation of histone H3 and deacetylation of histone H4 in the early phases of infection, before entry of L. monocytogenes into the host cell. The pore-forming activity is not implicated in causing the histone modifications. The modifications of the histones affect the down regulation of genes encoding proteins involved in the inflammatory response. Therefore, LLO may be significant in subverting the host immune response to L. monocytogenes. At its NH2-terminus it possesses a 25 residues long typical signal sequence excited during the secretion process. Moreover, in its NH2-terminus there is also a 19 amino acids PEST- like sequence that may target this toxin for degradation. The PEST-like sequence found in LLO and is considered crucial for virulence, given that mutants lacking the sequence lysed the host cell. Nevertheless, contrary to PEST's supposed role in protein degradation, evidence implies that the PEST-like sequence may control LLO production in the cytosol rather than increase degradation of LLO.

SEPT2 is a GTPase which is mandatory for cytokinesis and related to exocytosis. Septin-2 protein is able to hetero-oligomerize with Septin6, 7 and in addition takes part in the organization of new growth in organisms. SEPT2 is associated with a Tau-based paired helical filament core and contributes to the creation of neurofibrillary tangle as integral constituents of paired helical filaments.

g-synuclein(Originally known as a breast cancer specific gene product, BCSG1) is an acidic neuronal protein of 127 amino acids. Gamma-Synuclein is a member of the Synuclein protein family, which is believed to be involved in the pathogenesis of neurodegenerative diseases. High levels of Gamma-Synuclein have been found in advanced breast carcinomas suggesting a correlation between overexpression of SNCG and breast tumor development. Synuclein-Gamma is found mostly in the peripheral nervous system (in primary sensory neurons, sympathetic neurons, and motor neurons) and retina. SNCG is also identified in the brain, ovarian tumors, and in the olfactory epithelium. SNCG expression in breast tumors is a marker for tumor progression. A modification in the expression of gamma-synuclein has been detected in the retina of Alzheimer's patients.

Sialic Acid Binding Ig Like Lectin 10(SIGLEC10) is a part of the immunoglobulin superfamily that is expressed on eosinophils, B cells, monocytes and neutrophils. SIGLEC10 is an adhesion molecule that mediates sialic-acid dependent binding to cells.SIGLEC10 is a ligand for CD52, the target of the therapeutic monoclonal antibody Alemtuzumab. Also, it binds to Vascular adhesion protein 1 (VAP-1) and to the co-stimulatory molecule CD24.This binding is modulated by cis interactions of SIGLEC10 with sialated molecules on the same cell.

Crystallins are the main structural proteins of the vertebrate eye lens, where they maintain the transparency and refractive index of the lens. Crystallins are divided into 3 fprotein families, α, β, & γ families. Because lens central fiber cells lose their nuclei during development, these crystallins are prepared and then retained throughout life, making them extremely stable proteins. CRYBB1 is a beta basic group member and undergoes extensive cleavage at its N-terminal extension during lens maturation.

Plasma fibronectin level is elevated in severe coronary artery disease. Increased plasma fibronectin levels are related with venous thromboembolism (VTE) particularly in males, and extend the probable association between biomarkers and risk factors for arterial atherothrombosis and VTE. Fibronectin plays a role in several cellular processes, including tissue repair, embryogenesis, blood clotting, and cell migration/adhesion. Fibronectin consists in two main forms: 1) as an insoluble glycoprotein dimer that serves as a linker in the extracellular matrix and 2) as a soluble disulphide linked dimer found in the plasma. The plasma form is produced by hepatocytes, and the ECM form is synthesized by fibroblasts, chondrocytes, endothelial cells, macrophages, as well as certain epithelial cells. Fibronectin also takes part as a general cell adhesion molecule by anchoring cells to collagen or proteoglycan substrates. Fibronectin organizes cellular interaction with the ECM by binding to different components of the extracellular matrix and to membrane-bound Fibronectin receptors on cell surfaces.

TRAPPC3 is a part of the TRAPP complex that takes part in connection of transport vesicles to the cis-Golgi membrane. Additionally, TRAPPC3 is involved in vesicular transport from endoplasmic reticulum to Golgi.

TRIM21 is a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The 52 kDa Ro protein is part of the RoSSA ribonucleoprotein, which includes a single polypeptide and one of four small RNA molecules. The RoSSA particle localizes to both the cytoplasm and the nucleus. Ro/SSA interacts with autoantigens in patients with Sjogren syndrome and systemic lupus erythematosus. Ribonucleoprotein particle is composed of a single polypeptide and one of four small RNA molecules. The RoSSA is present in all mammalian cells studied but has no known function. At least 2 isoforms are present in nucleated and red blood cells, and tissue specific differences in Ro/SSA proteins were identified.

Crystallin gamma N (CRYGN) is a member of the Crystallins family. Crystallins are the main proteins of the vertebrate eye lens, where they preserve the transparency and refractive index of the lens. CRYGN is unique in the way that it has both beta and gamma crystallin protein motifs. The CRYGN is differentially controlled after early development, and is involved in cataract creation due to either age-related protein degradation or genetic mutation.

Signal-Regulatory Protein Gamma (SIRPG) belongs to the signal-regulatory protein (SIRP) family whose members are receptor-type transmembrane glycoproteins which negatively regulate the receptor tyrosine kinase-coupled signaling processes. SIRPG is also a part of the immunoglobulin superfamily.

Centromere proteins are a group of proteins which form and/or mediate the function of centromeres, the central structures of chromosomes to which spindle fibers/microtubuli attach and pull the chromosomes apart in cell division. Currently, 9 centromere proteins are known and designated CENPA to CENP-I. Most of the centromere proteins are targets of autoantibodies, the anti-centromere antibodies.
CENPB is the most important of the centromeric autoantigens: it has a molecular weight of approx. 66 kDa and plays an important role in the formation of the centromeric chromatin. CENPB antibodies are present in the sera of up to 80% of patients with CREST syndrome.

SEMA7A (semaphorin-7A isoform 1), is a membrane-bound semaphorin which is linked with cell surfaces via a glycosylphosphatidylinositol (GPI) linkage. SEMA7A encourages formation of focal adhesion complexes, activation of the protein kinase PTK2/FAK1 and subsequent phosphorylation of MAPK3 & MAPK1. SEMA7A takes a vital part in integrin-mediated signaling and functions in regulating cell migration as well as immune responses. In addition, SEMA7A promotes the production of proinflammatory cytokines by macrophages & monocytes.

Phospholipase A2 (PLA2) catalyzes the hydrolysis of the sn-2 position of membrane glycerophospholipids to liberate arachidonic acid (AA), a precursor of eicosanoids including prostaglandins and leukotrienes. The same reaction also produces lysophosholipids, which represent another class of lipid mediators.
The secretory PLA2 (sPLA2) family, in which 10 isozymes have been identified, consists of low molecular weight, Ca2+-requiring secretory enzymes that have been implicated in a number of biological processes, such as modification of eicosanoid generation, inflammation, and host defense.
This enzyme has been proposed to hydrolyze phosphatidylcholine (PC) in lipoproteins to liberate lyso-PC and free fatty acids in the arterial wall, thereby facilitating the accumulation of bioactive lipids and modified lipoproteins in atherosclerotic foci.
In mice, sPLA2 expression significantly influences HDL particle size and composition and demonstrate that an induction of sPLA2 is required for the decrease in plasma HDL cholesterol in response to inflammatory stimuli. Instillation of bacteria into the bronchi was associated with surfactant degradation and a decrease in large:small ratio of surfactant aggregates in rats.