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Syntaxin-2 (STX2) is a member of the syntaxin/epimorphin family of proteins. Syntaxin family members are cellular receptors for transport vesicles which participate in exocytosis in neutrophils. STX2 regulates epithelial-mesenchymal interactions and epithelial cell morphogenesis and activation. STX2 is a t-SNARE which localizes to the apical plasma membrane and intracellular vesicular structures. In addition, STX2, along with SNAP-23, is essential for regulated surfactant secretion.

Endoglin is a type I membrane glycoprotein located on cell surfaces and is part of the TGF beta receptor complex.
The protein consists of a homodimer of 180 kDA with disulfide links. It has been found on endothelial cells, activated macrophages, fibroblasts, and smooth muscle cells. Endoglin has been found to be part of the TGF-beta1 receptor complex. It thus may be involved in the binding of TGF-beta1, TGF-beta3, activin-A, BMP-2, and BMP-7. Beside TGF-beta signaling endoglin may have other functions. It has been postulated that endoglin is involved in the cytoskeletal organization affecting cell morphology and migration. Endoglin has a role in the development of the cardiovascular system and in vascular remodeling. Its expression is regulated during heart development . Experimental mice without the endoglin gene die due to cardiovascular abnormalities.

Connective Tissue Growth Factor belongs to the CCN family of proteins. The CCN family presently consists of six members in human also known as: Cyr61 (Cystein rich 61), CTGF (Connective Tissue Growth Factor), Nov (Nephroblastoma Overexpressed gene), WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins). The CCN genes encode secreted proteins associated with the Extracellular Matrix (ECM) and cell membrane.
CCN proteins are matricellular proteins which are involved in the regulation of various cellular functions including: proliferation, differentiation, survival, adhesion and migration. They are expressed in derivatives of the three embryonic sheets and are implicated in the development of kidney, nervous system, muscle, bone marrow, cartilage and bone. During adulthood, they are implicated in wound healing, bone fracture repair, and pathologies such as: fibrosis, vascular ailments and tumorigenesis.
Full length secreted CCN proteins can show an antiproliferative activity, whereas truncated isoforms are likely to stimulate proliferation and behave as oncogenes.
The full length protein consists of four modules: Module I shares partial identity with the N-terminal part of the Insulin-like Growth Factor Binding Proteins (IGFBPs).
Module II includes a stretch of 70amino acid residues – which shares sequence identity with the Von Willebrand Factor Type C repeat (VWC).
Module III contains sequences sharing identity with the Thrombospondin type 1 repeat (TSP1) (WSXCSXXCG), which is thought to be implicated in the binding of sulfated glycoconjugates and to be important for cell adhesion.
Module IV, also designated CT, is encoded by exon5. It is the leasts conserved one of the four domains at the level of nucleotide sequence, but it appears to be critical for several of the biological functions attributed to the CCN proteins. Module IV resembles the CT domain of several extracellular protein including, Von Willebrand's factor and mucins. Sequence similarities to heparin-binding motifs are also found within this domain.
Proteolysis of the secreted full-length CCN proteins that has been reported in the case of CCN2 and CCN3 might result in the production of CCN-derived peptides with high affinity for ligands that full-length CNN proteins bind only poorly. Amino-truncated CCN2 isoforms were biologically active whereas no specific biological activity has been attributed to the truncated CCN3. Although the molecular processes underlying the production of these secreted isoforms is presently unknown, it is important to note that proteolysis occur at the same amino acid residues in both CCN2 and CCN3. An elevated expression of CCN2 has also been detected by Northern blotting in human invasive mammary ductal carcinomas, dermatofibromas, pyogenic granuloma, endothelial cells of angiolipomas and angioleiomyomas, and in pancreatic tumors. A study performed with chondrosarcomas representative of various histological grades established that CCN2 expression was closely correlated with increasing levels of malignancy.
In agreement with CCN2 playing a role in brain tumor angiogenesis, immunocytochemistry studies indicated that both glioblastoma tumor cells and proliferating endothelial cells stained positive for CCN2. In astrocytomas, CCN2 expression was particularly elevated in high grade tumors, with a marked effect of CCN2 on cell proliferation. Downregulation of CCN2 expression in these cells was associated with a growth arrest at the G1/S transition while over-expression of CCN2 induced a two-fold increase of the number of cells in the G1 phase. Gene profiling analysis allowed to identify a set of about 50 genes whose expression might account for the proliferative activity of CCN2 in these cells.
CCN2 was seen in a higher proportion of mononuclear cells of patients with acute lymphoblastic leukemia.

TARC cDNA encodes a 94 amino acid precursor protein with a 23 amino acid residue signal peptide that is cleaved off to generate the 71 amino acid residue mature secreted protein. Along with CC chemokine family members, CCL-17 has approximately 24-29% amino acid sequence identity with RANTES, MIP-1a, MIP-1b, MCP-1, MCP-2, MCP-3 and I-309. TARC is expressed in thymus, and at a lower level in the lung, colon, and small intestine. TARC is in addition transiently expressed in stimulated peripheral blood mononuclear cells. Recombinant TARC has been shown to be chemotactic for T cell lines but not monocytes or neutrophils. CCL-17 is a specific functional ligand for CCR4, a receptor that is selectively expressed on T cells. CCL17 is one of a few Cys-Cys (CC) cytokine genes clustered on the q arm of chromosome 16. CCL17 shows chemotactic activity for T lymphocytes, but not monocytes or granulocytes. CCL17 binds to chemokine receptors CCR4 and CCR8. This chemokine plays important roles in T cell development in thymus as well as in trafficking and activation of mature T cells.

RAC1 is a GTPase which belongs to the RAS superfamily of small GTP-binding proteins. Members of this superfamily appear to regulate a diverse array of cellular events, including the control of cell growth, cytoskeletal reorganization, and the activation of protein kinases. RAC-1 regulates the actin cytoskeleton but also other cellular processes. RAC1 have been shown to be involved in the regulation of cell-cell adhesion.

Stem cell factor / KIT ligand (SCF) is a cytokine which binds CD117(c-Kit). SCF is also known as "steel factor" or "c-kit ligand". SCF exists in two forms, cell surface bound SCF and soluble (or free) SCF. Soluble SCF is produced by the cleavage of surface bound SCF by metalloproteases.
SCF is a growth factor important for the survival, proliferation, and differentiation of hematopoietic stem cells and other hematopoietic progenitor cells. One of its roles is to change the BFU-E (burst-forming unit-erythroid) cells, which are the earliest erythrocyte precursors in the erythrocytic series, into the CFU-E (colony-forming unit-erythroid).

Cardiotrophin-like cytokine factor 1 (CLCF1) is a member of the interleukin 6 family of cytokines, which are involved in cell signaling via phosphorylation of gp130. CLCF1 has a sequence of 225 amino acids with a 27 aa signal peptide, having a molecular mass of 22kDa in the mature form, and the maximum homology to cardiotrophin-1 and ciliary neurotrophic factor. CLCF1 is actively secreted from cells by forming a complex with soluble type I CRLF1 or soluble CNTFR. Defects in the CLCF1 gene cause cold-induced sweating syndrome 2 (CISS2). The CISS2 syndrome is typified by profuse sweating after exposure to cold as well as congenital physical abnormalities of the head and spine.

Interleukin-1 alpha is a proinflammatory cytokine produced by a wide variety of cell types, including macrophages, osteoblasts, monocytes and hepatocytes. Circulating levels of are normally low and only rise after stimulation by agents such as those produced byinflammation, infection or microbial endotoxins. IL-1 alpha possesses a wide variety of biological activities and exerts its effects by binding to specific cell surface receptors.

CD86, also known as B7-2 or Cluster of Differentiation 86 is a protein necessary for T cell activation and survival, it is expressed on cells that are antigen-presenting cells and acts as costimulatory signals for T cells. CD86 is the ligand for CD28 (for autoregulation and intercellular association) and CTLA-4 (for attenuation of regulation and cellular disassociation), two different proteins.

Clathrin, light chain A (CLTA) is a member of the clathrin family. Clathrin, which is a large, soluble protein, is comprised of heavy and light chains. CLTA is one of 2 clathrin light chain proteins which are supposed to function as regulatory elements. CLTA is a key cytosolic coat protein in pits and vesicles originating from the plasma membrane and the trans-Golgi network. In receptor-mediated endocytosis, receptor proteins are encapsulated by Clathrin-coated vesicles.

CD9 which is found on the surface of exosomes is a cell surface glycoprotein which is interacts with integrins and various transmembrane superfamily proteins. CD9 is involved in platelet activation and aggregation and also regulates paranodal junction formation. CD9 takes part in cell adhesion and migration and also promotes muscle cell fusion. CD9 is necessary for the egg-sperm fusion during mammalian fertilization.

ICAM-1 also called CD54 is a single chain membrane glycoprotein expressed on the surface of a variety of non-haematopoietic and haematopoietic cell types and has roles in signal transduction, cell signaling and lymphocyte adhesion. ICAM1 binds to integrins such as CD11a / CD18, or CD11b / CD18. ICAM1 is also used by Rhinovirus as a receptor. ICAM-1 is an intercellular adhesion molecule constantly present in low concentrations in the membranes of leukocytes and endothelial cells. When stimulated by cytokine the concentrations significantly increase. ICAM-1 can be stimulated by interleukin-1 (IL-1) and tumor necrosis factor alpha (TNFA) and is expressed by the vascular endothelium, macrophages and lymphocytes. ICAM-1 is a ligand for LFA-1 which is a receptor found on leukocytes. Upon activation, leukocytes bind to endothelial cells via ICAM-1/LFA-1 and then transmigrate into tissues.
ICAM-1 is implicated in subarachnoid hemorrhage (SAH). Levels of ICAM-1 are shown to be notably elevated in patients with SAH.
Soluble ICAM-1 is detectable in the plasma and is elevated in patients with various inflammatory conditions.

T cell immunoreceptor with Ig and ITIM domains or TIGIT, is an immune receptor located on part of T cells and Natural Killer Cells(NK). TIGIT is also known as Vstm3 and WUCAM. The receptor can bind with high affinity to dendritic cells(DCs), CD155(PVR) on macrophages, etc., and it can bind with lower affinity to CD112(PVRL2). TIGIT can inhibit the cytotoxicity of Natural Killer Cells through its ITIM domain via antibodies against the interaction with PVR and the activity is directed. It has been show on research that TIGIT-Fc fusion molecule can have interaction with PVR on dendritic cells and elevate its IL-10 secretion level or lower the secretion on IL-12 under the stimulation of LPS, moreover, it can inhibit the activation of T cell in vivo.

Chitodextrinase is a unique membrane-bound endoenzyme. The chitodextrinase enzyme cleaves soluble oligomers, but not chitin, to the di- and trisaccharides. Chitodextrinase is unable to solubilize chitin, but it can catalyze the hydrolysis of high to low molecular weight soluble chitin oligosaccharides.

Carcinoembryonic Antigen-Related Cell Adhesion Molecule 6 (CEACAM6) is a part of the human carcino-embryonic antigen (CEA) family. CEACAM6 belongs to the glycosylphosphatidylinositol-linked immunoglobulin superfamily which is involved in various human cancers. CEACAM6 is linked to the progression of pancreatic cancer.

MCSFR which is also familiar as CSF1R, is part of the type3 subfamily of receptor tyrosine kinases. MCSFR is expressed mainly on cells of the monocyte and macrophage lineage, stem cells, and in the growing placenta. Most of the biological effects of this cytokine are mediated by MCSFR. MCSFR contains an extracellular ligand-binding domain, a single membrane-spanning segment, and an intracellular tyrosine kinase domain. Originally CSF1 and this receptor were implicated as vital for normal trophoblastic implantation as well as monocyte development. The role of CSF1/CSF1R in normal mammary gland development is actually very interesting since this connection has also been discovered in the biology of breast cancer with the results of abnormal expression of CSF1 and its receptor. Likewise, in Alzheimer's disease and after brain injuries an increased level of CSF1R was found in the microglia, which causes the microglia to become more active.

Interleukin-1 alpha is a proinflammatory cytokine produced by a wide variety of cell types, including macrophages, osteoblasts, monocytes and hepatocytes. Circulating levels of are normally low and only rise after stimulation by agents such as those produced by inflammation, infection or microbial endotoxins. IL-1 alpha possesses a wide variety of biological activities and exerts its effects by binding to specific cell surface receptors.

Mycobacterium antigen ESAT6 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. 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. Early secretory antigen 6 (ESAT6) and cell filtrate protein 10 (CFP10) are 2 antigens secreted as a complex by the replicating Mycobacterium tuberculosis complex (MTC).

Hepatitis A virus cellular receptor 1 (HAVCR1) is a membrane receptor for both human hepatitis A virus (HHAV) and TIMD4. HAVCR1 is a type I trans-membrane structural glycoprotein located in the renal proximal tubule epithelial cells. HAVCR1 protein may be involved in the control of asthma and allergic diseases. The reference genome represents an allele which retains a MTTVP amino acid segment that presents defense against atopy in HHAV seropositive individuals.

ANXA2 is part of the annexin family and is involved in the regulation of cellular growth and in signal transduction pathways. ANXA2 protein functions as an autocrine factor which increases osteoclast formation and bone resorption. ANXA2 is associated with sickle cell osteonecrosis. Reduced ANXA2 expression is associated with osteosarcoma metastases. ANXA2 is part of the putative cell surface vitamin D binding protein binding site complex and functions to mediate the chemotactic cofactor effect. ANXA2 is involved in dysferlin deficiency and in muscular dystrophies. Human colon adenocarcinoma cell differentiation is related with an up-regulation of ANXA2.

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.

Regulated upon Activation, Normal T-cell Expressed, and Secreted or RANTES is an 8 kDa protein classified as a chemotactic cytokine or chemokine. It has recently been renamed CCL5. RANTES is chemotactic for T cells, eosinophils and basophils and plays an active role in recruiting leukocytes into inflammatory sites. With the help of particular cytokines (i.e. IL-2 and IFN-?) that are released by T cells, RANTES also induces the proliferation and activation of certain natural killer (NK) cells to form CHAK (CC-Chemokine-activated killer) cells. It is also a HIV-suppressive factor released from CD8+ T cells. This chemokine has been localized to chromosome 17 in humans.

TNFRSF13B (TACI) is a transmembrane receptor protein found predominantly on the surface of B cells (a significant part of the immune system). TACI was at first discovered owing to its ability to interact with calcium-modulator and cyclophilin ligand (CAML). Later on, it was found that TACI plays a key role in humoral immunity by interacting with two members of the TNF family. Also, TACI controls T cell-independent B cell antibody responses, isotype switching, and B cell homeostasis.