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IL-16 is a pleiotropic cytokine that functions as a chemoattractant, a modulator of T cell activation, and an inhibitor of HIV replication. The signaling process of IL-16 is mediated by CD4. The product of this gene undergoes proteolytic processing, which is found to yield two functional proteins. IL-16 functions exclusively attributed to the secreted C-terminal peptide, while the N-terminal product may play a role in cell cycle control. Caspase 3 is reported to be involved in the proteolytic processing of this protein. Two transcript variants encoding different isoforms have been found for this gene.
IL-16 stimulates a migratory response in cd4+ lymphocytes, monocytes, and eosinophils. Also induces t-lymphocyte expression of interleukin 2 receptor, ligand for cd4.

Macrophage Inflammatory Proteins belong to the family of chemotactic cytokines known as chemokines. In humans, there are two major forms, MIP-1a and MIP-1b that are now also named CCL3 and CCL4. Both factors are produced by macrophages after they are stimulated with bacterial endotoxins. MIP-1a and MIP-1b activate human granulocytes (neutrophils, eosinophils and basophils) which can lead to acute neutrophilic inflammation. MIP-1a and MIP-1b induce synthesis and release of other pro-inflammatory cytokines such as interleukin-1 (IL-1), IL-6 and TNF-alpha from fibroblasts and macrophages. CCL3 and CCL4 genes are both located on human chromosome 17.

Anthrax toxin receptor 2, also known as ANTXR2, takes part in the configuration of little blood vessels (capillaries). ANTXR2 helps the toxin that leads to anthrax to attach to cells and trigger illness. ANTXR2 is necessary for cellular interactions with laminin and the extracellular matrix.

TNFRSF14, a member of the TNF receptor superfamily, is a type I transmembrane protein. TNFRSF14 is expressed in peripheral blood T cells, B cells, monocytes and in various tissues enriched in lymphoid cells. TNFRSF14 operates as a co-stimulatory factor for the activation of lymphoid cells and as a deterrent to infection by herpesvirus. Additionally, TNFRSF14 encourages the proliferation of T cells, and triggers apoptosis of various tumor cells.

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, gamma delta 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.

Osteostat is the cytokine that binds to TNFRSF18/AITR/GITR and is important for interactions between activated T-lymphocytes and endothelial cells and may modulate T-lymphocyte survival in peripheral tissues. Osteostat is expressed at high levels in the small intestine, ovary, testis, kidney and endothelial cells after stimulation by lipopolysaccharides.
Osteostat protein is detectable in human microvascular EC and is highly up-regulated by IFN-alpha and IFN-beta. Osteostat inhibit differentiation of osteoclasts from monocytic precursor cells. Osteostat suppresses the early stage of osteoclastogenesis via inhibition of macrophage colony-stimulating factorinduced receptor activator of NF-kappaB (RANK) expression in the osteoclast precursor cells. Osteostat does not inhibit lipopolysaccharide-induced RANK expression in monocytes and dendritic cells, or activation-induced RANK expression in T cells. Osteostat is a novel regulator of osteoclast generation and substantiate the major role played by the endothelium in bone physiology.

Interleukin 2 receptor is a protein that involves immune responses that are mediated through T cells. The IL2 receptor exists in three ways in which it can bind to IL2. CD25 is the lowest affinity (a monomer of the alpha subunit), therefore, it is not part of the signal transduction process. The highest affinity has three heterotrimer subunits (alpha/beta/gamma), the intermediate affinity is found to have gamma/beta subunit heterodimer. Both forms are part of the receptor mediated endocytosis and mitogenic signals transduction from IL2.

PRDX3 is part of the peroxiredoxin family of antioxidant enzymes, that reduces hydrogen peroxide and alkyl hydroperoxides. PRDX3 is particularly located in the mitochondria and involved in the regulation of cellular redox status by serving as a primary line of defense against H2O2 produced during respiration. PRDX3 is a significant regulator of the abundance of mitochondrial H(2)O(2), which itself promotes apoptosis in cooperation with other mediators of apoptotic signaling. PRDX3 mitochondrial protein is significantly decreased in Alzheimer Disease and Down Syndrome.

GH is a member of the somatotropin/prolactin family of hormones which play an important role in growth control. The gene, along with four other related genes, is located at the growth hormone locus on chromosome 17 where they are interspersed in the same transcriptional orientation; an arrangement which is thought to have evolved by a series of gene duplications. The five genes share a remarkably high degree of sequence identity. Alternative splicing generates additional isoforms of each of the five growth hormones, leading to further diversity and potential for specialization. This particular family member is expressed in the pituitary but not in placental tissue as is the case for the other four genes in the growth hormone locus. Mutations in or deletions of the gene lead to growth hormone deficiency and short stature.

Argininosuccinate lyase (ASL) is a member of the lyase 1 family. ASL is an enzyme which catalyzes the reversible breakdown of Argininosuccinate (ASA) yielding the amino acids arginine and fumarate. ASL which is located in the liver cytosol is the 4th enzyme of the urea cycle and involved in the biosynthesis of arginine in all species and the production of urea in ureotelic species. While Argininosuccinate synthetase (ASS) catalyzes the formation of argininosuccinate from citrulline and aspartate, ASL breaks down the newly formed argininosuccinate into L-arginine and fumarate. L-arginine continues within the urea cycle to form urea and orinthine, whereas fumarate can enter the citric acid cycle. ASL gene Mutations result in the autosomal recessive disorder argininosuccinic aciduria, or argininosuccinic acid lyase deficiency.

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.

ANXA6 is part of the family of calcium-dependent membrane and phospholipid binding proteins. ANXA6 mediats the endosome aggregation and vesicle fusion in secreting epithelia during exocytosis. ANXA6 correlates with CD21. ANXA6 regulates the release of Ca(2+) from intracellular stores. ANXA6 is differentially expressed in the lumbar spinal cord from rats submitted to peripheral lesion during neonatal period.

Human IL-36b belongs to the IL-1 family that includes IL-1b, IL-1a, IL-1ra, IL-18, IL-36ra (IL1F5), IL-36b (IL1F8), IL-36g (IL1F9), IL-37 (IL1F7) and IL-38 (IL-1F10). The IL-1 family members display a 12 b-strand, b-trefoil configuration, and are thought to have ascended from a mutual ancestral gene. IL-36 beta is known to be actively secreted. Cells expressing IL-36 beta include resting and activated monocytes and B cells. The receptor for IL-36 beta is a blend of IL-1 Rrp2 and IL-1 RAcP. Recombinant IL-36 beta stimulates processes involving NF-kB and MAPK in an IL-1 Rrp2-dependent manner.

CD226 belongs to the Ig-superfamily containing 2 Ig-like domains of the V-set. CD226 is a 65kDa glycoprotein expressed on the surface NK cells, platelets, monocytes and a subset of T cells. CD226 facilitates cellular adhesion of platelets and megakaryocytic cells to vascular endothelial cells. CD226 also plays a role in megakaryocytic cell maturation.

The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that play important roles in mammalian growth and development. IGF1 mediates many of the growth-promoting effects of growth hormone (GH; MIM 139250). Early studies showed that growth hormone did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as 'somatomedin' (Daughaday et al., 1972). Three main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

Granzyme-B (GZMB) is essential for target cell lysis in cell-mediated immune responses. GZMB is related to an activation cascade of caspases responsible for apoptosis execution. GZMB cuts caspase-3, -7, -9 and 10 to activate enzymes mediating apoptosis.

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.

B-cell CLL/lymphoma 7A (BCL7A) is a member of the BCL7 family. BCL7A is directly involved, with Myc and IgH, in a three-way gene translocation in a Burkitt lymphoma cell line. Thru gene translocation, the N-terminal region of the BCL7A gene is disrupted, which is assumed to be connected to the pathogenesis of a subset of high-grade B cell non-Hodgkin lymphoma. The N-terminal portion involved in the translocation includes the region which shares a compelling sequence similarity with those of BCL7B and BCL7C. Chromosomal anomalies involving BCL7A may be a cause of B-cell non-Hodgkin lymphoma.

Ubiquitin thioesterase OTUB2 (OTUB2) is a member of the peptidase C65 family. OTUB2 functions as a hydrolase which can remove conjugated ubiquitin from proteins in vitro and may thus play a key regulatory role at the level of protein turnover by preventing degradation.

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.

TREM1 is a transmembrane receptor protein that is involved in monocytic activation and in the inflammatory response. TREM1 is expressed on the surface of neutrophils, mature monocytes and macrophages. TREM1 stimulates neutrophil and monocyte-mediated inflammatory responses. TREM1 also triggers the release of pro-inflammatory chemokines and cytokines, as well as increased surface expression of cell activation markers. Furthermore, TREM1 is an amplifier of inflammatory responses that are triggered by bacterial and fungal infections and is a fundamental mediator of septic shock. The expression of the soluble form of TREM1 increases during sepsis and can consequently be used as a biological marker for septic shock. TREM1 is strongly expressed in acute inflammatory lesions caused by bacteria and fungi. Increased TREM1 expression on monocytes is related to both infectious and noninfectious inflammatory processes.
TREM1 is vastly expressed in adult liver, lung and spleen than in corresponding fetal tissue. TREM1 is also expressed in the lymph node, placenta, spinal cord and heart tissues. TREM1 expression is more elevated in peripheral blood leukocytes than in the bone marrow and in normal cells than malignant cells. TREM1 is expressed at low levels in the early development of the hematopoietic system and in the promonocytic stage and at high levels in mature monocytes.

Calnexin (CANX) belongs to the calnexin family of molecular chaperones. Calnexin is a calcium-binding, ER-associated protein that interacts briefly with newly synthesized N-linked glycoproteins, facilitating protein folding and assembly. Calnexin may also have a key role in the quality control of protein folding by retaining incorrectly folded protein subunits within the ER for degradation. Calnexin grants long-term protection of wild-type Shaker protein from ER-associated degradation. Polypeptide substrate recognition by Calnexin requires specific conformations of the Calnexin protein. Calnexin dwindles with aging and might contribute to a cytoprotection in an array of human age-related diseases.

The IL1RL1 gene is a member of the IL-1 receptor family, encoding a transmembrane protein with a structure similar to IL-1R1. IL1RL1 is a receptor for interleukin-33, its stimulation recruits MYD88, IRAK1, IRAK4, and TRAF6, followed by phosphorylation of MAPK3/ERK1 and/or MAPK1/ERK2, MAPK14, and MAPK8. IL1RL1 may possibly be involved in helper T-cell function. IL1RL1 is highly expressed in kidney, lung, placenta, stomach, skeletal muscle, colon and small intestine.
A soluble form of the IL1RL1 is produced from the same gene by alternative splicing and was shown to be expressed in several cell types including fibroblasts and mast cells. Soluble IL1RL1 also acts as a negative regulator of Th2 cytokine production and high levels have been reported in several disease states and conditions including asthma, sepsis and myocardial infarction.
Analysis of the similar gene in mouse suggested that the IL1RL1 receptor can be induced by proinflammatory stimuli, and may be involved in the function of helper T cells.

B cell-activating factor (BAFF) enhances B-cell survival in vitro and is a regulator of the peripheral B-cell population. Overexpression of Baff in mice results in mature B-cell hyperplasia and symptoms of systemic lupus erythematosus (SLE). Also, some SLE patients have increased levels of BAFF in serum. Therefore, it has been proposed that abnormally high levels of BAFF may contribute to the pathogenesis of autoimmune diseases by enhancing the survival of autoreactive B cells. The protein encoded by this gene is a receptor for BAFF and is a type III transmembrane protein containing a single extracellular cysteine-rich domain. It is thought that this receptor is the principal receptor required for BAFF-mediated mature B-cell survival.