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Cystatin-A is the intracellular inhibitor of cysteine proteinase cathepsin B (CatB) and belongs to family 1 of the cystatin superfamily of inhibitor proteins. CSTA is a stefin that functions as a cysteine protease inhibitor, forming tight complexes with papain and the cathepsins B, H, and L. It has been proposed that extracellular CatB together with other classes of proteinases are all subjected to a cascade-like manner of activation. CatB and its inhibitor Cystatin-A are involved in degradation of extracellular matrix proteins during tissue remodeling. CSTA is one of the precursor proteins of cornified cell envelope in keratinocytes and plays a role in epidermal development and maintenance. Cystatin-A has been reported to be found in high concentrations in epithelial cells, polymorphonuclear leukocytes and lymphoid tissue. Stefins may be used as prognostic and diagnostic tools for cancer.

Adenylosuccinate lyase (ADSL) is an enzyme which converts adenylosuccinate to AMP and fumarate as part of the purine nucleotide cycle. ADSL is involved in both de novo synthesis of purines and formation of adenosine monophosphate from inosine monophosphate. ADSL catalyzes 2 reactions in AMP biosynthesis: the removal of a fumarate from succinylaminoimidazole carboxamide (SAICA) ribotide to yield aminoimidazole carboxamide ribotide (AICA) and removal of fumarate from adenylosuccinate to yield AMP. Defects in the ADSL are the cause of adenylosuccinase deficiency (ADSL deficiency). ADSL deficiency is an autosomal recessive disorder distinguished by the accumulation in the body fluids of succinylaminoimidazole-carboxamide riboside (SAICA-riboside) and succinyladenosine (S-Ado). Adenylosuccinase deficiency results in succinylpurinemic autism, psychomotor retardation, and in some cases, growth retardation associated with muscle wasting and epilepsy.

RNH1 belongs to the proteinaceous cytoplasmic RNase inhibitors family which occur in many tissues and binds to both intracellular and extracellular RNases. In addition to control of intracellular RNases, the inhibitor may have a part in the regulation of angiogenin. The 50kDa RNH1 binds to ribonucleases and holds them in a latent form. Since neutral and alkaline ribonucleases possibly play a critical role in the turnover of RNA in eukaryotic cells, RNH1 may be vital for control of mRNA turnover; the interaction of eukaryotic cells with ribonuclease may be reversible in vivo.

Integrins are heterodimeric integral membrane proteins composed of an alpha chain and a beta chain. This I-domain containing alpha integrin combines with the beta 2 chain (ITGB2) to form a leukocyte-specific integrin referred to as macrophage receptor 1 ('Mac-1'), or inactivated-C3b (iC3b) receptor 3 ('CR3'). The alpha M beta 2 integrin is important in the adherence of neutrophils and monocytes to stimulated endothelium, and also in the phagocytosis of complement coated particles. Integrin alpha-m/beta-2 is implicated in various adhesive interactions of monocytes, macrophages and granulocytes as well as in mediating the uptake of complement-coated particles. CD-11b is identical with cr-3, the receptor for the ic3b fragment of the third complement component. CD-11b probably recognizes the r-g-d peptide in c3b. Integrin alpha-m/beta-2 is also a receptor for fibrinogen, factor x and icam1. it recognizes p1 and p2 peptides of fibrinogen gamma chain.

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. Lentiviruses are transmitted as single-stranded, positive-sense, enveloped RNA viruses. Upon entry of the target cell, the viral RNA genomeis converted to double-stranded DNAby a virally encoded reverse transcriptasethat is present in the virus particle. This viral DNA is then integrated into the cellular DNA by a virally encoded integraseso that the genome can be transcribed. Once the virus has infected the cell, two pathways are possible: either the virus becomes latentand the infected cell continues to function, or the virus becomes active and replicates, and a large number of virus particles are liberated that can then infect other cells.

PPARGC1A is transcriptional coactivator for steroid receptors and nuclear receptors which increases the transcriptional activity of PPARG and thyroid hormone receptor on the uncoupling protein promoter. PPARGC1A regulates main mitochondrial genes that contribute to the program of adaptive thermogenesis and plays an important role in metabolic reprogramming in response to dietary availability through coordination of the expression of many genes participate in glucose and fatty acid metabolism. PPARGC1A induces the expression of PERM1 in the skeletal muscle and takes part in the integration of the circadian rhythms and energy metabolism.

Autophagy Related 3 (ATG3) is a conjugating enzyme essential for the cytoplasm to vacuole transport (Cvt), autophagy, and mitochondrial homeostasis. ATG3 is localizes to the cytoplasm and is expressed in tissues with predominant levels found in kidney, placenta, liver, heart and skeletal muscle. ATG3 catalyzes a reaction which is necessary for autophagy. That reaction is the formation of the Atg8-phosphatidylethanolamine (ATG-PE) conjugate.

Hepatitis B is one of a few known non-retroviralviruses which employ reverse transcriptionas a part of its replication process. (HIV, a completely unrelated virus, also uses reverse transcription, but it is a retrovirus.) HBV invades the cell by binding to surface receptor and become internalized. The viral core particles then migrate to the hepatocyte nucleus and the partially double-stranded, relaxed circular genomes (RC-DNA) are repaired to form a covalently closed circular DNA (cccDNA), which is the template for viral genomic and sub-genomic RNAs by cellular RNA polymerase II. Of these, the pregenomic RNA (pgRNA is selectively packaged into progeny capsids and is then reverse-transcribed into new RC-DNA. The core can either bud into the endoplasmic reticulum to be enveloped or exported from the cell or recycled back into the genome for conversion to cccDNA.

H3N2 is a subtype of the influenza A virus. Its name derives from the forms of the two kinds of proteinson the surface of its coat, hemagglutinin(H) and neuraminidase(N). H3N2 exchanges genes for internal proteins with other influenza subtypes. H3N2 has tended to dominate in prevalence over H1N1, H1N2, and influenza B. H3N2 strain descended from H2N2by antigenic shift, in which genes from multiple subtypes re-assorted to form a new virus. Both the H2N2and H3N2 strains contained genesfrom avian influenzaviruses.

PGAM1 is part of the phosphoglycerate mutase family. PGAM1 is an essential component of glucose and 2,3-BPGA (2,3-bisphosphoglycerate) metabolism and catalyzes the reversible reaction of 3-phosphoglycerate (3-PGA) to 2-phosphoglycerate (2-PGA) in the glycolytic pathway. PGAM1 is a dimeric enzyme containing, in different tissues, different proportions of a slow-migrating muscle (MM) isozyme, a fast-migrating brain (BB) isozyme, and a hybrid form (MB). PGAM1 mutations lead to muscle phosphoglycerate mutase deficiency, a.k.a. glycogen storage disease X.

Glypican 4, also known as GPC4, is part of a family of glycosylphosphatidylinositol (GPI)-anchored heparan sulphate proteoglycans (HSPGs) which take part in the control of cell division and growth regulation. GPC4 is broadly expressed in human tissues, including lung, kidney, heart, placenta, skeletal muscle, and pancreas. In addition, GPC4 has been shown to be present in astrocytes, haematopoietic-progenitor and bone-marrow-stromal cells.

The 26S proteasome is a multicatalytic proteinase complex with a well ordered structure composed of two complexes- a 20S core and a 19S regulator. PSMD11 is a non-ATPase subunit of the 19S regulator. The 20S core is composed of four rings of 28 non-identical subunits; two rings are composed of 7 alpha subunits and two rings are composed of 7 beta subunits. The 19S regulator is composed of a base that contains six ATPase subunits and two non-ATPase subunits, and a lid that contains up to ten non-ATPase subunits. Proteasomes are spread throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An indispensable function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides.

CD44 is a cell-surface glycoprotein that plays a role in cell-cell interactions, cell adhesion and migration. CD44 is a receptor for hyaluronic acid and also interacts with other ligands, such as osteopontin, collagens, and matrix metalloproteinases. CD44 participates in a wide variety of cellular functions such as lymphocyte activation, recirculation and homing, hematopoiesis, and tumor metastasis. CD44 and CD49d are putative activity markers and CD44 a potential novel therapeutic target in multiple sclerosis. Increased CD44 antigen is associated with relapses in non-small cell lung cancers.

NCS1 is part of the neuronal calcium sensor gene family, which encode calcium-binding proteins expressed primarily in neurons. NCS1 regulates G protein-coupled receptor phosphorylation in a calcium-dependent manner and can substitute for calmodulin. NCS1 is related with secretory granules and modulates synaptic transmission and synaptic plasticity. NCS1 regulates GRK1 and substitutes for calmodulin. NCS1 stimulates PI4KB kinase activity and participates in long-term synaptic plasticity through its interaction with PICK1. NCS1 takes part in neuron differentiation through inhibition of the activity of N-type voltage-gated calcium channel.

ACOT11 is a protein with acyl-CoA thioesterase activity towards medium (C12) and long-chain (C18) fatty acyl-CoA substrates. Expression of a similar murine protein in brown adipose tissue is induced by cold exposure and repressed by warmth. Expression of the mouse ACOT11 has been linked to obesity, with higher expression found in obesity-resistant mice compared with obesity-prone mice.

AIMP1 (EMPA2 or p43) is a cytokine that is specifically induced by apoptosis, and it is involved in the control of angiogenesis, inflammation, and wound healing. The release of the AIMP1 cytokine renders the tumor-associated vasculature sensitive to tumor necrosis factor. Furthermore, AIMP1 is involved in the stimulation of inflammatory responses after proteolytic cleavage in tumor cells.

IL-12 is a heterodimeric cytokine that stimulates the production of interferon gamma from T-cells and natural killer cells, and also induces differentiation of Th1 helper cells. It is an initiator of cell-mediated immunity.

TPD52L1 (hD53, hD53L1) is a member of D52 gene family and overexpressed in human breast carcinoma. TPD52L1 contains coiled-coil motif, which is responsible for homo- and heteromeric interaction, and may be a regulator of cell proliferation and calcium-mediated signal transduction. Moreover, TPD52L1 interacts with the mitogen-activated protein kinase kinase kinase 5 (MAP3K5/ASK1) and positively regulates MAP3K5-induced apoptosis.

Acyl-CoA synthetase family member 2, also known as ACSF2 is a member of the ATP-dependent AMP-binding enzyme family. Acyl-CoA synthetases are a family of enzymes which catalyze the thioesterification of fatty acids with coenzymeA to form activated intermediates, which play a basic part in lipid metabolism as well as homeostasis of lipid-related processes. ACSF2 is required for the complex of lipid synthesis, energy production via beta-oxidation, protein acylation and fatty-acid dependent transcriptional regulation. Moreover, ACSF2 is required for fatty acid import into cells by the process of vectorial acylation.

Glycophorins A & B (GYPA &GYPB) are the main sialoglycoproteins of the human erythrocyte membrane which carry the antigenic determinants for the MN and Ss blood groups. Along with the M or N and S or s antigens which normally occur in all populations, approximately 40 related variant phenotypes were identified. These variants comprise all the variants of the Miltenberger complex and some isoforms of Sta, as well as Dantu, Sat, He, Mg, and deletion variants Ena, S-s-U- and Mk. GYPA is significant for the function of SLC4A1 and is necessary for high activity of SLC4A1. GYPA is involved in translocation of SLC4A1 to the plasma membrane. GYPA is also a receptor for: the influenza virus, Plasmodium falciparum erythrocyte-binding antigen 175 (EBA-175); binding of EBA-175 is dependent on sialic acid residues of the O-linked glycans and is also a receptor for Hepatitis A virus (HAV).

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is wilyde used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

T-cell antigen CD7 (CD7) is a type I transmembrane glycoprotein which is expressed on pluripotential hemapoietic cells, nearly all human thymocytes and some peripheral blood T cells. The CD7 molecule is missing in a subset of human T cells under some physiologic conditions. An increase in CD7 negative T cells can be observed in a number of inflammatory skin diseases.

Hepatitis B virus is the main cause for human liver disease, chronic infection frequently causes liver cancer and cirrhosis. The e antigen is found in the circulation, it is found during the active HBV infection, positive result indicates the risk for contagiousness, and is also used as indicator for the effectiveness of HBV treatment. Positive anti-HBeAg specifies an active stage of acute HBV infection that is in its final stages, the risk for contagiousness is dramatically reduced. HBe VLP Antibody is a monoclonal antibody to the aggregated HBeparticle, used with HBe-VLP antigen to manufacture competitive HBe antibody rapid test or ELISA assay.

Cyclin-dependent kinase inhibitor 1B (CDKN1B) is a member of the Cip/Kip family of cyclin dependent kinase (Cdk) inhibitor proteins. The CDKN1B protein binds to and prevents the activation of cyclin E-CDK2 or cyclin D-CDK4 complexes, and so controls the cell cycle progression at G1. CDKN1B is often referred to as a cell cycle inhibitor protein since its major function is to stop or slow down the cell division cycle. The degradation of the CDKN1B protein, which is triggered by its CDK dependent phosphorylation and ensuing ubiquitination by SCF complexes, is compulsory for the cellular transition from inactive to the proliferative state.