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Since April 2012, cases of the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) have been identified in various countries. Coronaviruses are the cause of the common cold, SARS (severe acute respiratory syndrome) and other severe illnesses with high mortality rates, all are classified into coronavirus family. MERS-CoV is a new type of SARS found in the coronavirus family causing severe pneumonia with sudden and serious respiratory illness with high mortality rates as well. Since January 27th 2015, the WHO has reported 956 human cases, including 351 deaths. More cases of the new coronavirus strain are expected. Like in other coronaviruses, large surface spike glycoprotein is a central structural protein of this virus; it is located above the virion surface to bind and enter into the target cell. Spike protein has 2 domains- S1 and S2. The S1 domain is responsible for cellular tropism and interaction with target cell, while the S2 domain is responsible for membrane fusion. The C-terminal of S1 domain contains a receptor binding domain, and is also a potential target for vaccine development and an antigen for diagnosis.

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.

Potassium Channel Tetramerisation Domain Containing 11 (KCTD11) is a 232 amino acid regulator of neuronal differentiation which induces growth arrest, apoptosis and the expression of p27 (cyclin-dependent kinase inhibitor). KCTD11 is expressed most highly in cerebellum. KCTD11 functions as an antagonist of the Hedgehog pathway and activator of the caspase cascade and among its related super-pathways are Melatonin Signaling and Activation of cAMP-Dependent PKA.

CNTF is a polypeptide hormone whose actions appear to be restricted to the nervous system where it promotes neurotransmitter synthesis and neurite outgrowth in certain neuronal populations. The protein is a potent survival factor for neurons and oligodendrocytes and may be relevant in reducing tissue destruction during inflammatory attacks. A mutation in this gene, which results in aberrant splicing, leads to ciliary neurotrophic factor deficiency, but this phenotype is not causally related to neurologic disease. In addition to the predominant monocistronic transcript originating from this locus, the gene is also co-transcribed with the upstream ZFP91 gene. Co-transcription from the two loci results in a transcript that contains a complete coding region for the zinc finger protein but lacks a complete coding region for ciliary neurotrophic factor.
CNTF is a survival factor for various neuronal cell types. Seems to prevent the degeneration of motor axons after axotomy.

HCV is a small 50nm, enveloped, single-stranded, positive sense RNAvirus in the family Flaviviridae.
HCV has a high rate of replication with approximately one trillion particles produced each day in an infected individual. Due to lack of proofreading by the HCV RNA polymerase, the HCV has an exceptionally high mutation rate, a factor that may help it elude the host's immune response. Hepatitis C virus is classified into six genotypes(1-6) with several subtypes within each genotype. The preponderance and distribution of HCV genotypes varies globally. Genotype is clinically important in determining potential response to interferon-based therapy and the required duration of such therapy. Genotypes 1 and 4 are less responsive to interferon-based treatment than are the other genotypes (2, 3, 5 and 6).

Human immunodeficiency virus (HIV) is a retrovirusthat can lead to a condition in which the immune systembegins to fail, leading to opportunistic infections. HIV primarily infects vital cells in the humanimmune systemsuch as helper T cells(specifically CD4+ T cells), macrophagesand dendritic cells. HIV infection leads to low levels of CD4+ T cells through three main mechanisms: firstly, direct viral killing of infected cells; secondly, increased rates of apoptosisin infected cells; and thirdly, killing of infected CD4+ T cells by CD8 cytotoxic lymphocytesthat recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunityis lost, and the body becomes progressively more susceptible to opportunistic infections. HIV was classified as a member of the genus Lentivirus, part of the family of Retroviridae. Lentiviruses have many common morphologies and biological properties. Many species are infected by lentiviruses, which are characteristically responsible for long-duration illnesses with a long incubation period.HIV-1 gp41 Subtype-c reacts to the specific antibody from HIV1 infection, in lateral flow assay, it is usually coated on the membrane to capture the specific antibody from HIV1 infection.

Chemokine (C-X-C motif) ligand 11 (CXCL11) is a small cytokine belonging to the CXC chemokinen family that is also called inducible T-cell alpha chemoattractant (I-TAC) and (IP-9). I-TAC is highly expressed in peripheral blood leukocytes, pancreas and liver, with moderate levels in thymus, spleen and lung and low expression levels were in small intestine, placenta and prostate. Gene expression of CXCL11 is strongly induced by IFN-g and IFN-b, and weakly induced by IFN-a. The I-TAC chemokine elicits its effects on its target cells by interacting with the cell surface chemokine receptor CXCR3, with a higher affinity than do the other ligands for this receptor, CXCL9 and CXCL10. I-TAC is chemotactic for activated T cells. The CXCL11 gene is located on human chromosome 4 along with many other members of the CXC chemokine family.

Semaphorin-4D (CD100) is a member of the semaphorin family containing 1 Ig-like C2-type domain, 1 PSI domain and 1 Sema domain. CD100 is the cell surface receptor forPLXN1B and PLXNB2 which plays a central role in cell-cell signaling. CD100 stimulates the migration of cerebellar granule cells and of endothelial cells, regulates dendrite and axon branching and morphogenesis. In addition, CD100 has a role in the immune system; it promotes signaling via SRC and PTK2B/PYK2, which subsequently mediates activation of phosphatidylinositol 3-kinase and of the AKT1 signaling cascade.

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 acidsand 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.

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.

TBE is caused by tick-borne encephalitis virus (TBEV), a member of the family Flaviviridae.
A closely related virus in Far Eastern Eurasia, Russian spring-summer encephalitis virus (RSSEV).
The family Flaviviridae includes other tick-borne viruses are closely related to TBEV and RSSEV, such as Omsk hemorrhagic fever virus & Kyasanur Forest virus.
Louping ill virus is also a member of this family.

MICA (MHC class I chain-related gene A) is a transmembrane glycoprotein that functions as a ligand for human NKG2D. A closely related protein, MICB, shares 85% amino acid identity with MICA. These proteins are distantly related to the MHC class I proteins. They possess three extracellular Ig-like domains, but they have no capacity to bind peptide or interact with ?2-microglobulin. The genes encoding these proteins are found within the Major Histocompatibility Complex on human chromosome 6. The MICA locus is highly polymorphic with more than 50 recognized human alleles. MICA is absent from most cells but is frequently expressed in epithelial tumors and can be induced by bacterial and viral infections. MICA is a ligand for human NKG2D, an activating receptor expressed on NK cells, NKT cells,gammadelta T cells, and CD8+beta T cells. Recognition of MICA by NKG2D results in the activation of cytolytic activity and/or cytokine production by these effector cells. MICA recognition is involved in tumor surveillance, viral infections, and autoimmune diseases.

G/U mismatch-specific DNA glycosylase (mug) is a part of the TDG/mug DNA glycosylase family. Mug is necessary for DNA damage lesion repair in stationary-phase cells. Mug protein removes three N4-ethenocytosine and takes away s the uracil base from mismatches in the order of U:G>U:A. The enzyme Uracil-N-Glycosylase removes uracil from the DNA leaving an AP position. Mug is also able to hydrolyzing the carbon-nitrogen bond among the sugar-phosphate backbone of the DNA and the mispaired base. The complementary strand guanine plays a role in substrate recognition.

SEMA3C, also known as Semaphorin 3C, is a member of the semaphorin family 3 that are grouped into 8 major classes based on phylogenetic tree analyses and structure. Class 3 have an important function after traumatic central nervous system injuries. SEMA3C regulates neuronal and non-neuronal cells associated with the traumatic injury due to their presence in the scar tissue. SEMA3C is expressed in all somatic motor neurons, in cardiac neural crest cells during development and in lung buds. The SEMA3C functions are mediated through binding to the Plexin-D1 and Neuropilin 1 or Neuropilin 2 coreceptor complex. SEMA3C activates integrins in certain cells, so besides its repulsive activities, it also acts as a chemoattractant.

Epidermal Growth Factor­like Domain Multiple 6 (EGFL6) belongs to the EGF repeat superfamily of proteins, whose members are involved in the regulation of cell cycle, proliferation, and developmental processes. EGFL6 gene product contains a signal peptide, suggesting that EGFL6 is secreted; an EGF repeat region consisting of four complete EGF-like repeats and 1 partial EGF-like repeat, 3 of which have a calcium-binding consensus sequence; an arg-gly-asp integrin association motif; and a MAM domain, which is assumed to have an adhesive function. Within shared regions, human EGFL6 shares 75% and 78% amino acid sequence identity with the mouse and rat orthologs, respectively. EGFL6 is expressed in various fetal tissues during early development such as the lung, heart, liver, spleen, cochlea and the placenta, as well as meningioma tumors.

Breast Cancer Anti-Estrogen Resistance 1 (BCAR1) is a Src family kinase substrate which takes part in a range of cellular events such as migration, survival, transformation, and invasion. BCAR1 plays a vital role for tyrosine kinase-based signaling related to cell adhesion.

Energy Homeostasis Associated (ENHO) participates in glucose homeostasis maintenance and lipid metabolism. ENHO is expressed in the liver and the brain. The role of ENHO in obesity or diabetes is studied.

BIRC7 is a part of the inhibitor of apoptosis protein (IAP) family and contains a single copy of a baculovirus IAP repeat (BIR) as well as a RING-type zinc finger domain. The BIR domain is necessary for inhibitory activity & cooperates with caspases, while the RING finger domain sometimes increases anti-apoptotic activity but doesn’t inhibit apoptosis by itself. 2 transcript variants encoding diverse isoforms have been found for this gene. The 2 isoforms have dissimilar antiapoptotic characteristics, with isoform a protecting cells from apoptosis induced by staurosporine and isoform b defending cells from apoptosis induced by etoposide.
BIRC7 has direct contact with several caspases together with caspase-3, caspase-7, & caspase –9. BIRC7 inhibits the activation of caspase-9 induced by Apaf-1, cytochrome c, and dATP.

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.

FAM3C is a member of the FAM3 family and holds a GG domain. Pancreatic cancer-derived cells demonstrate a difference in expression of this protein. FAM3C is a downstream target gene for the Nkx5-1 transcription factor, and there for takes part in cell differentiation and proliferation through inner ear embryogenesis. In addition, FAM3C has a role in retinal laminar formation and promotes epithelial to mesenchymal transition.

Low affinity immunoglobulin gamma Fc region receptor III-A (FCGR3A) is a receptor for the Fc portion of immunoglobulin G, and is involved in the elimination of antigen-antibody complexes from the circulation, as well as other antibody-dependent responses. FCGR3A needs to associate with the gamma subunit of Fc epsilon. The FCGR3A receptor is expressed on natural killer (NK) cells as an integral membrane glycoprotein anchored through a transmembrane peptide, while FCGR3B is expressed on polymorphonuclear neutrophils (PMN) where the receptor is anchored through a phosphatidylinositol (PI) linkage. In addition, FCGR3A is expressed on macrophages, subpopulation of T-cells, immature thymocytes and placental trophoblasts. FCGR3A mediates antibody-dependent cellular cytotoxicity (ADCC) and other antibody-dependent responses, such as phagocytosis. FCGR3A gene mutations are linked with susceptibility to recurrent viral infections, susceptibility to systemic lupus erythematosus, and alloimmune neonatal neutropenia.

C9orf103 is a member of the gluconokinase gntK/gntV family. C9orf103 takes part in carbohydrate acid metabolism and D-gluconate degradation.

T-cell surface glycoprotein CD3 zeta chain (CD247) is a member of the CD3Z/FCER1G family. CD247 is T-cell receptor zeta, which along with T-cell receptor alpha/beta and gamma/delta heterodimers, and also with CD3-gamma, -delta and -epsilon, creates the T-cell receptor-CD3 complex. The zeta chain has a central role in coupling antigen recognition to several intracellular signal-transduction pathways. Low expression of the CD247 antigen causes impaired immune response.

CD93, is a receptor or else an element of a larger receptor complex for C1q, MBL2-mannose-binding lectin and SPA-pulmonary surfactant protein A. CD93 mediates the enhancement of phagocytosis in monocytes as well as macrophages upon interaction with soluble defense collagens. CD93 takes part in the intercellular adhesion. Furthermore, CD93 was expressed on (pre) plasmablasts/plasma cells, including long-lived plasma cells which demonstrated decreased cell cycle activity, high levels of isotype-switched Ig secretion, as well as modification of the transcriptional network. CD93 is vital for the maintenance of plasma cells in bone marrow niches.