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Killer-cell immunoglobulin-like receptors (KIRs), are a family of cell surface glycoproteins found on Natural Killer (NK) Cells, which are important cells of the immune system. They control the killing function of these cells by interacting with MHC class I molecules, which are expressed on all cell types. This interaction allows them to identify virally infected cells or tumor cells that have a distinctive low level of Class I MHC on their surface. The majority of KIRs are inhibitory, which means that their recognition of MHC suppresses the cytotoxic activity of their NK cell. Only a limited number of KIRs have the capacity to activate cells.
The KIR genes are found in a cluster on chromosome 19q13.4 within the 1 Mb leukocyte receptor complex (LRC). KIR molecules are extremely polymorphic, meaning their gene sequences differ significantly between individuals, so that different individuals have different arrays/repertoires of KIR genes.
The KIR proteins are categorized by the number of extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM). Whereas KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals.
KIR2DL3 is an inhibitory Killer Cell Ig-like Receptor (KIR, previously called p58 KIR, cl-6, NKAT2 or KIR-K7), which recognizes class I MHC molecules (HLA-Cw1, -Cw3, -Cw7, and Cw8). KIR2DL3 inhibits the activity of NK cells thus preventing cell lysis.

Killer-cell immunoglobulin-like receptors (KIRs), are a family of cell surface glycoproteins found on Natural Killer (NK) Cells, which are important cells of the immune system. They control the killing function of these cells by interacting with MHC class I molecules, which are expressed on all cell types. This interaction allows them to identify virally infected cells or tumor cells that have a distinctive low level of Class I MHC on their surface. The majority of KIRs are inhibitory, which means that their recognition of MHC suppresses the cytotoxic activity of their NK cell. Only a limited number of KIRs have the capacity to activate cells.
The KIR genes are found in a cluster on chromosome 19q13.4 within the 1 Mb leukocyte receptor complex (LRC). KIR molecules are extremely polymorphic, meaning their gene sequences differ significantly between individuals, so that different individuals have different arrays/repertoires of KIR genes.
The KIR proteins are categorized by the number of extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM). Whereas KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals.
KIR2DS4 is an activating Killer Cell Ig-like Receptor (KIR, previously called p50 KIR, p50.3, cl39, or KAR-K1), which may recognize class I MHC molecules. KIR2DS4 does not inhibit the activity of NK cells.

TNFRSF4, also known as TNF Receptor Superfamily Member 4, is a T cell co-stimulatory molecule which belongs to the TNF receptor superfamily. TNFRSF4 coordinates with other co-stimulatory substances such as CD28, CD40, CD30, CD27 and 4-1BB to control the activation of the immune response. TNFRSF4 takes a vital part in antigen-specific T cell expansion as well as survival. TNFRSF4 is up-regulated on CD4+ and CD8+ T cells upon engagement of the TCR by antigen presenting cells along with co-stimulation by CD40-CD40 Ligand and CD28-B7. In addition, TNFRSF4 regulates cytokine production from T cells, antigen presenting cells, natural killer cells and natural killer cells. TNFRSF4 regulates cytokine receptor signaling.

CD40 belongs to the TNF-receptor super family. CD40 has been found to be vital in mediating a wide range of immune and inflammatory responses including T cell-dependent immunoglobulin classswitching, memory B cell development, and germinal center formation. AT-hook transcription factor AKNA isaccounted to coordinately regulate the expression of CD40 and its ligand, which is significant forhomotypic cell interactions. Adaptor protein TNFR2 interacts with CD40 and functions as a mediator of thesignal transduction. The interaction of CD40 and its ligand is found to be essential for amyloid-beta-inducedmicroglial activation, and therefore is considered to be an early event in Alzheimer disease pathogenesis.

CD55 belongs to the RCA (regulators of complement activation) family characterized by 4-30 SCRs (short consensus repeats) in their plasma-exposed regions. CD55 is widely expressed in malignant tumors and nevertheless functions as an inhibitor of the complement system.

CD74 (HLA class II histocompatibility antigen gamma chain isoform b), is a transmembrane protein (on antigen presenting cells) which is the invariant chain that chaperones MHC class IIdimers from the endoplasmic reticulum to the cell surface. CD74 is expressed by cells of both T lymphocyte and Blymphocyte lineages. CD74 upregulated in several cancers and is also expressed by non immune cells during inflammation. Diseases related with CD74 include thymic epithelial neoplasm and gastroduodenitis. Among its related super-pathways are Immune System and Immune response Antigen presentation by MHC class II. In addition CD74 functions as cell surface receptor for the cytokine MIF.

Lipocalin-2 also called Neutrophil Gelatinase Associated Lipocalin (NGAL) belongs to a family of lipocans which include 25 proteins (including a1-microglobulin and b-lactoglobulin), which are characterized by their ability to bind small lipophilic substances in their hydrophobic core.
They thereby serve as transporters of substances like retinal, biliverdins & prostaglandins. There are indications that NGAL is involved in modulation of the inflammatory response and is found in the plasma of patients after stroke.

Gastrokine 3 (GKN3P) is a Pseudogene, which May inhibit gastric epithelial cell proliferation.

Procalcitonin is a peptide hormone mainly produced by the C cells of the thyroid and certain endocrine cells of the lung. Under normal expression conditions, procalcitonin is immediately cleaved into three specific fragments, an N terminal residue, calcitonin and katacalcin. Levels of unprocessed procalcitonin rise significantly after bacterial infection, trauma or shock.

Procalcitonin is a peptide hormone mainly produced by the C cells of the thyroid and certain endocrine cells of the lung. Under normal expression conditions, procalcitonin is immediately cleaved into three specific fragments, an N terminal residue, calcitonin and katacalcin. Levels of unprocessed procalcitonin rise significantly after bacterial infection, trauma or shock.

Complement Factor Properdin (CFP) which is a plasma glycoprotein, is a positive regulator of the alternative complement pathway of the innate immune system. CFP binds and stabilizes the C3- and C5-convertase enzyme complexes in a feedback loop that eventually ends with formation of the membrane attack complex and lysis of the target cell. Mutations in CFP lead to 2 forms of properdin deficiency that cause high susceptibility to meningococcal infections.

Guanine nucleotide binding proteins are heterotrimeric signal-transducing molecules comprising alpha, beta, and gamma subunits. GNAI1 represents the alpha subunit of an inhibitory complex. Guanine nucleotide-binding protein G(i) subunit alpha (GNAI1) functions to transmit information from cell surface receptors to intracellular effectors. GNAI1 binds guanine nucleotide, can hydrolyze GTP, and can interact with other proteins. GNAI1 is part of a complex that responds to beta-adrenergic signals by inhibiting adenylate cyclase. In addition, GNAI1 functions to open atrial potassium channels.

LIN7B (VELI2), is a member of the Velis family. Velis family contains minor synaptic proteins which interact with other proteins at the post-synaptic density (PSD) of neuronal synapses. Velis which contain the PDZ motif, participate in recruiting cell adhesion molecules, receptors, and channels. Lin7B protein is ubiquitously expressed with a high expression in the brain, liver, and testis. Lin7B localizes at the synaptic junctions in neurons, bind to CASK, which is a neurexin-binding protein highly concentrated in synapses, and Mint1, a binding partner with a vesicle trafficking protein.

GPT catalyzes the reversible transamination between alanine and 2-oxoglutarate to create pyruvate and glutamate. GPT has a crucial part in the intermediary metabolism of glucose and amino acids. GPT is broadly used as an indicator of liver reliability or hepatocellular destruction in clinical tests.

Lactoferrin is a glycoprotein that belongs to the transferrin family of iron binding proteins. It is found in human breast milk as well as most epithelial surface secretions including tears, nasogastric, saliva, and bronchial. Lactoferrin binds 2 molecules of iron with very high affinity. Lactoferrin inhibits bacterial growth by withholding iron, its N-terminal region is an antimicrobial peptide. Lactotransferrin acts synergistically with lysozyme to potentiate the activity of both proteins. The multifunctional protein lactoferrin has many physiological possible roles. It is often referred to as an innate defense protein and frequently serves as the first line of defense in protection against pathogens. It has been shown to have the ability to bind iron, it is a natural anti-bacterial, anti-fungal and anti-viral, it is an antioxidant and it also has immunomodulatory properties. It has many beneficial properties, which make it a good candidate for a number of product applications. Considerable research is currently going on to explain the various suggested biological functions of lactoferrin.

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.

MDH2 catalyzes the reversible oxidation of malate to oxaloacetate, utilizing the NAD/NADH cofactor system in the citric acid cycle. MDH2 is localized to the mitochondria and takes part in the malate-aspartate shuttle that functions in the metabolic coordination between cytosol and mitochondria. MDH2 is highy expressed in the adrenal system, small intestine, heart and pancreas.

Bronchoalveolar lavage fluid from mice with experimentally induced allergic pulmonary inflammation contains a novel 9.4 kDa cysteine-rich secreted protein, RELM-alpha (FIZZ1, found in inflammatory zone). RELM-alpha is a secreted protein that has a restricted tissue distribution with highest levels in adipose tissue stroma. Murine RELM-alpha (FIZZ1) is the founding member of a new gene family including two other murine genes expressed, respectively, in intestinal crypt epithelium (RELM-beta) and white adipose tissue (Resistin), and two related human genes.
RELMalpha inhibits the differentiation of 3T3-L1 preadipocytes into adipocytes but has no effect on proliferation of 3T3-L1 preadipocytes. RELMalpha is able to form heterooligomers with resistin but not RELMbeta. Since RELMalpha is expressed by adipose tissue and it is a secreted factor, our findings suggest that RELMalpha may be involved in the control of the adipogenesis as well as in the process of muscle differentiation.
In the lung, RELM-alpha is induced by hypoxia and was renamed as hypoxia-induced mitogenic factor (HIMF). HIMF strongly activated Akt phosphorylation. The phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 (10 micromol/L) inhibited HIMF-activated Akt phosphorylation. It also inhibited HIMF stimulated RPSM proliferation. Thus, the PI3K/Akt pathway, at least in part, mediates the proliferative effect of HIMF. Further studies showed that HIMF had angiogenic and vasoconstrictive properties. HIMF increased pulmonary arterial pressure and vascular resistance. Further studies suggest that HIMF regulates apoptosis and may participate in lung alveolarization and maturation.

Cytotoxic and Regulatory T Cell Molecule, also known as CRTAM belongs to the immunoglobulin superfamily which complies with the structural characteristics of the JAM family and is phylogenetically more closely related to nectin-like proteins. CRTAM is implicated in epithelial cell adhesion. Furthermore, CRTAM interacts with CADM1 as well as promotes natural killer (NK) cell cytotoxicity.

Adiponectin is an important negative regulator in hematopoiesis and immune systems. It may be involved in ending inflammatory responses through its inhibitory functions. Inhibits endothelial nf-kappa-b signaling through a camp-dependent pathway. Inhibits tnf-alpha- induced expression of endothelial adhesion molecules. Involved in the control of fat metabolism and insulin sensitivity.

CCL23 (MIP-3) is a ligand for the CCR1chemokine receptor. CCL23 is one of several cytokine genes clustered on the q-arm of chromosome 17, in a locus containing several other CC chemokines. MIP-3 chemoattracts monocytes, resting T-lymphocytes and neutrophils, but not activated lymphocytes. Furthermore, it was shown that MIP-3 inhibits colony formation of bone marrow myeloid immature progenitors. MIP-3 is mainly expressed in lung and liver tissue, but can be also found in bone marrow and placenta, as well as in some cell lines of myeloid origin.
Alternative splicing of the CCL23 gene produces 2 mRNAs which encode a short (CK?8) and a long (CK?81) isoform of the MIP-3. CK?8 cDNA encodes a 120 amino acid residue precursor protein with a putative 21 a.a. residue signal peptide which is cleaved to generate a 99 a.a. residue mature CK?8 (a.a. 22-120). Further N-terminal processing of the 99 a.a. residue variant can produce a 75 a.a. residue CK?8 (a.a. 46-120) which is considerably more active than the 99 a.a. residue variant.
MIP-3 may be involved in the malignant progression of certain human cancer cells which overexpress ErbB2 through the transactivation of ErbB2 tyrosine kinase. MIP-3 may also be involved in angiogenesis via upregulation of matrix metalloproteinase MMP-2 expression.

Alpha 1-microglobulin (A1M) is a lipocalin superfamily member (kernal lipocalins). A1M is a low molecular weight protein component of plasma. A1M is distributed in plasma and extravascular compartments of all organs. Alpha-1 Microglobulin is found in mammals, birds, amphibians and fish. The primary sites of A1M synthesis are the liver and the kidney. Around the opening of the lipocalin pocket three lysyl residues are situated; those residues carry yellow-brown modification derived from the binding and degradation of heme and kynurenin (a tryptophan metabolite). A1-Microglobulin’s reductase and dehydrogenase have broad biological substrate specificity properties due to its’ free cysteine side-chain which is located in a flexible loop. Alpha-1-microglobulin is glycosylated by three separate carbohydrate chains: two complex carbohydrates which are N-linked to asparagines at residues 17 and 96, and the other simple carbohydrate which is O-linked to threonine at position 5. The carbohydrates comprise 22% of the total molecular mass of the protein. The glycosylation varies between species.
A1M exists in two forms- a free form and complexed to other macromolecules: in humans- complexed to immunoglobulin A (IgA), in rat- complexed to alpha-1-inhibitor-3. Free A1M is exceptionally heterogeneous in charge (therefore also known as protein HC), and is found tightly linked to a chromophore. The free Alpha-1-microglobulin is a monomeric protein composed of one 188 residue polypeptide and contains three cysteines, two of which (residues 75 and 173) form a conserved intra-molecular disulphide link. The chromophoric group is covalently bound to the free cysteine residue at position 34. A1M binds retinol as a major ligand, but this is probably distinct from its covalent chromophore.
Half of all human plasma A1M (approximately 0.03mg/ml) forms a 1:1 complex with about 5% of plasma immunoglobulin A. The resulting macromolecular complexes’ molecular weight is 200000, and a plasma concentration of 0.3mg/ml. The complex can exhibit both antibody activity and affect many of the biological actions of free Alpha-1-microglobulin.
Alpha-1-microglobulin was first discovered in pathological human urine.
It was suggested that A1M might be involved in tissue defense against reactive oxygen species, oxidation by heme and kynurenin. Evidence also suggests that A1M functions in the regulation of the immune system. Other functions include inhibition of stimulation of cultured lymphocytes by protein antigens; induction of cell division of lymphocytes, a mitogenic effect that can either be enhanced or inhibited by the action of other plasma components; inhibition of neutrophil granulocyte migration in vitro; and inhibition of chemotaxis.

Deoxyribose-phosphate aldolase (DERA) is a member of the deoC/fbaB aldolase protein family involved in the carbohydrate degradation pathway. DERA catalyzes the conversion of 2-deoxy-D-ribose 5-phosphate to D-glyceraldehyde 3-phosphate and an acetyldehyde.

ApoA5 is an important regulator of serum triglyceride concentrations. An ApoA5 mouse nock-out model produced an approximately four fold increase in serum triglycerides, whereas a knock-in model human ApoA5 produced 50-70% lower concentrations of mouse serum triglycerides. Furthermore, peroxisome proliferators-activated receptoragonists, which are used clinically to lower serum triglyceride concentrations, cause increased ApoA5 mRNA expression. There is very little known about ApoA5 protein in human serum. Lately, it was established that ApoA5 is present in the human serum and it can be detected by polyclonal antibodies against both the HN2 and COOH termini, but at much lower concentration than other apolipoproteins.