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Plasmodium falciparum is a protozoan parasite, one of the species of Plasmodium that cause malaria. Malaria parasites are members of the Apicomplexa. Apicomplexa are characterized by a set of organelles found in some stages of the parasite's life cycle. These organelles, collectively known as apical organelles because of their localization at one end of the parasite, are involved in interactions between the parasite and host. In particular, the apical organelles have been implicated in the process of host cell invasion. In the case of Plasmodium, three distinct invasive forms have been identified: sporozoite, merozoite, and ookinete.

Forty-two antigenic domains were identified across the hepatitis A virus (HAV) polyprotein by using a set of 237 overlapping 20-mer synthetic peptides spanning the entire HAV polyprotein. Nineteen antigenic domains were found within the structural proteins, and 22 were found within the nonstructural proteins, with 1 domain spanning the junction of VP1 and P2A proteins. Five of these domains were considered immunodominant, as judged by both the breadth and the strength of their immunoreactivity. One domain is located within the VP2 protein at position 57-90 aa. A second domain, located at position 767-842 aa, contains the C-terminal part of the VP1 protein and the entire P2A protein. A third domain, located at position 1403-1456 aa, comprises the C-terminal part of the P2C protein and the N-terminal half of the P3A protein. The fourth domain, located at position 1500-1519 aa, includes almost the entire P3B, and the last domain, located at position 1719-1764 aa, contains the C-terminal region of the P3C protein and the N-terminal region of the P3D protein. Four of the five most immunoreactive domains are derived from small HAV proteins and/or encompass protein cleavage sites separating different HAV proteins.

BDNF promotes the survival of neuronal populations that are all located either in the central nervous system or directly connected to it. BDNF is a major regulator of synaptic transmission and plasticity at adult synapses in many regions of the cns. The versatility of BDNF is emphasized by its contribution to a range of adaptive neuronal responses including long-term potentiation (ltp), long-term depression (ltd), certain forms of short-term synaptic plasticity, as well as homeostatic regulation of intrinsic neuronal excitability.

Complement factor H (CFH) is an important regulatory component of the alternative pathway of complement. CFH is prevents complement activation on host cells and tissues, mainly the kidney. CFH controls the formation and decay of the alternative pathway C3/C5 convertase and acts as a cofactor for factor I which proteolytically inactivates C3b when C3b is bound to factor H. The N-terminal 5 domains of CFH bind to C3b and inhibit binding of factor B thus reducing the formation of C3/C5 convertase. CFH also binds to preformed C3/C5 convertases and causes quick release of the catalytic subunit Bb. These activities are necessary for controlling the spontaneous activation of the alternative pathway amplification process in plasma. In addition, CFH controls the formation and decay of these enzymes when C3b is attached to the surface of particles.

Apolipoprotein E3 (ApoE) is a 34kDa protein component of serum chylomicrons, VLDL, and HDL particles. ApoE mediates the binding, uptake, and catabolism of these particles as a result of interactions with the ApoE receptor and LDL receptors in the liver and brain. ApoE is imperative in fatty acid homeostasis and memory formation. Polymorphisms encode 3 variants (ApoE2, 3, 4), which are differentially connected to the development of atherosclerosis and neurogenerative disorders, mainly Alzheimer's disease.

Interleukin-17 receptor A isoform 1 (IL17RA) is a cytokine receptor which binds interleukin 17. IL17RA is a potent inducer of the maturation of CD34-positive hematopoietic precursors into neutrophils. IL17RA is a type 1 membrane glycoprotein which binds with low affinity to interleukin 17A. The IL17RA protein and Interleukin 17A has a pathogenic role in many inflammatory and autoimmune diseases such as rheumatoid arthritis.

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.

Immediate Early Response 3 (IER3) functions in the protection of cells from Fas- or tumor necrosis factor type alpha-induced apoptosis. IER3 has a role in the ERK signaling pathway by inhibiting the dephosphorylation of ERK by phosphatase PP2A-PPP2R5C holoenzyme. In addition, IER3 serves as an ERK downstream effector mediating survival. As a member of the NUPR1/RELB/IER3 survival pathway, IER3 provides pancreatic ductal adenocarcinoma with significant resistance to cell stress, such as starvation.

INHBC, the beta C chain of inhibin, belongs to the TGF-beta superfamily. INHBC formulates heterodimers with beta A and beta B subunits. Other members of the TGF-beta superfamily are Actv's and Inhibins, hormones with contradictory roles which take part in pituitary, hypothalamic, and gonadal hormone secretion, as well as differentiation and growth of numerous cell types.

MAGEA6 belongs to the MAGEA family, which directs the expression of tumor antigens which are seen on a human melanoma by autologous cytolytic T lymphocytes (CTL). Members of the MAGEA family encode proteins with 50 to 80% sequence identity to each other. The MAGE genes, which are clustered at chromosomal location Xq28, were originally isolated from separate kinds of tumors, and based on their practically exclusive tumor-specific expression in adult tissues; they are objects for cancer immunotherapy. MAGEA genes’ promoters and first exons exhibit substantial variability, implying that the existence of the MAGEA gene family enables the same function to be expressed under different transcriptional controls. MAGEA genes are implicated in several hereditary disorders, such as dyskeratosis congenita.

The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms, β, γ, ε, σ, ζ, τ and η that have been identified in mammals. The 14-3-3 epsilon, a subtype of the 14-3-3 family of proteins, was thought to be brain and neuron-specific. It has been shown to interact with CDC25 phosphatases, RAF1 and IRS1 proteins, suggesting its role in diverse biochemical activities related to signal transduction, such as cell division and regulation of insulin sensitivity. It has also been implicated in the pathogenesis of small cell lung cancer.

LYVE1 is a selective marker of the lymphatic endothelium & a surface endocytic receptor for both soluble and immobilized hyaluronan, LYVE1 is an extracellular glycosaminoglycan that plays a role in cell adhesion and migration. LYVE1 functions in lympathic hyaluronan transport and is involved in tumor metastasis. Recombinant human LYVE1 was expressed in and purified by conventional chromatography techniques. The normal adult human choroid is endowed with a significant number of LYVE-1 positive macrophages. LYVE-1 is expressed in a reticulum cell neoplasm in an axillary lymph node. This reticulum cell sarcoma is a lymphatic sinus lining cell sarcoma which might represent another subtype of reticulum cell sarcomas.
LYVE-1 immunohistochemistry is a functional method for detecting lymphatics invaded by cancer cells, and detailed examination of the submucosa around the tumor is important for predicting LN metastasis.

SAA1 protein is an acute phase apolipoprotein reactant which is produced mostly by hepatocytes and under regulation of inflammatory cytokines. SAA1 (Serum amyloid A1) protein is produced mainly in the liver and circulates in low levels in the blood. The SAA1 seems to have a role in the immune system. SAA1 protein levels increase in the blood and other tissues under conditions of inflammation. SAA1 may facilitate the repair of injured tissues; it also acts as an antibacterial agent, and signals the migration of germ-fighting cells to sites of infection. SAA1 also functions as an apolipoprotein of the HDL complex.
Elevated levels of SAA1 ultimately affect secondary amyloidosis, extracellular amassing of amyloid fibrils, resulting from a circulating precursor, in a variety of tissues and organs. The most widespread type of amyloidosis appears secondary to chronic inflammatory disease, mainly rheumatoid arthritis. The SAA1 cleavage product a designated amyloid protein A is deposited systemically as amyloid in vital organs such as the liver, spleen, and kidneys in chronic inflammatory diseases patients. These deposits are extremely insoluble and resistant to proteolysis; they disrupt tissue structure and compromise performance.

Proprotein Convertase Subtilisin/Kexin Type 1 Inhibitor (PCSK1N) takes part in the control of the neuroendocrine secretory pathway. PCSK1N inhibits prohormone convertase 1, which regulates the proteolytic cleavage of neuroendocrine peptide precursors. PCSK1Nslows down convertase-mediated processing of proopiomelanocortin and proenkephalin and also monitors the intracellular timing of PCSK1.

IL1R2 is a cytokine receptor which is a part of the interleukin-1 receptor family. IL1R2 is expressed mainly by T cells, endothelial cells and fibroblasts. IL1R2 binds IL1A, IL1B and IL1RN preventing them from binding to their regular receptors and thus inhibiting the transduction of their signaling. Also, Interleukin-4 antagonizes the activity of interleukin-1 by inducing the expression and release of this protein.

H1N1 is a subtype specie of Influenza A virus. H1N1 Influenza Virus has mutated into various strains such as the Spanish Flustrain, mild humanflu strains, endemic pigstrains, and various strains found in birds.
The Influenza A Virusis a globular particle about 100nm in diameter, sheathed in a lipid bilayer derived from the plasma membrane of its host. Studded in the lipid bilayer are two integral membrane proteins some 500 molecules of hemagglutinin ("H") and some 100 molecules of neuraminidase ("N"). Within the lipid bilayer are 3000 molecules of matrix protein and 8 pieces of RNA. Each of the 8 RNA molecules is associated with many copies of a nucleoprotein, several molecules of the three subunits of its RNA polymerase some "non-structural" protein molecules of uncertain function.

Melanoma Antigen Family B,10 also known as MAGEB10 is a member of the B subfamily of the melanoma associated antigen protein family. MAGEB10 is specifically expressed in testis and tumor cells. One of the diseases associated with MAGEB10 is melanoma.

Recombinant Hirudin is a potent thrombin inhibitor originally derived from the medicinal leech. Hirudin acts directly on thrombin rather than through other clotting factors. The mechanism of Hirudin-thrombin appears to be unique. The conversion of fibrinogen into fibrin by the serine protease enzyme thrombin is a major event in the final stages of blood coagulation. In the final stages of coagulation prothrombinase converts prothrombin into thrombin. Fibrin is subsequently cross linked by factor XIII to form a blood clot. The primary inhibitor of thrombin in normal blood circulation is antithrombin III. The anticoagulatant activity of hirudin is derived from its ability to inhibit the pro-coagulant activity of thrombin (similar to antithrombin III activity). Hirudin is the strongest natural inhibitor of thrombin. Hirudin binds to and inhibits only the activity of thrombin forms with a specific activity on fibrinogen contrasting to antithrombin III activity. Therefore, hirudin has a thrombolytic activity since it prevents or dissolves the formation of clots and thrombi. Hirudin also has therapeutic significance in blood coagulation disorders, in the treatment of skin hematomas and of superficial varicose veins. Hirudin does not hinder with the biological activity of other serum proteins and can also act on complexed thrombin, thus having an advantage over more common anticoagulants and thrombolytics. It is complicated to extract large quantities of hirudin from natural sources; therefore a method for producing and purifying hirudin using recombinant biotechnology has been developed.

Protein A is a cell wall component produced by several strains of Staphylococcus aureus. The recombinant Protein A is genetically engineered protein and holds 5 IgG-binding regions of protein A. Recombinant Protein A functions basically the same as native Protein A and is perfect for purification of polyclonal or monoclonal IgG antibodies. Protein A binds to human IgG1, IgG2 and IgG4, mouse IgG2a, IgG2b and IgG3 and rat IgG2c. Protein A also binds to total IgG from rabbit, pig, dog, cat, and guinea pig.

IL-1 alpha is derived fromactivated macrophages. IL1A proteins take part in the inflammatory response, being identified as endogenous pyrogens, and stimulate the release of prostaglandin and collagenase from synovial cells.IL-1 alpha stimulates thymocyte proliferation by inducing il-2 release, b-cell maturation and proliferation, and fibroblast growth factor activity.

Trypsin (EC3.4.21.4) is part of the serine protease family. Trypsin cleaves lysine and arginine at the C-terminal side of the peptide. The hydrolysis rate is slower if an acidic residue is on either sides of the cleavage site and no cleavage occurs if a proline residue is on the carboxyl side of the cleavage site. Trypsin optimum pH is pH-7 to 9. Trypsin will also hydrolyze ester and amide linkages of synthetic derivatives of amino acids such as: benzoyl L-arginine ethyl ester (BAEE), p-toluenesulfonyl- L-arginine methyl ester (TAME), tosyl-L-arginine methyl ester, N-α-benzoyl-L-arginine p-nitroanilide (BAPNA), L-lysyl-p-nitroanilide, and benzoyl-L-tyrosine ethyl ester (BTEE). Serine protease inhibitors that inhibit recombinant trypsin include TLCK (N-p-tosyl-L-lysine chloromethyl ketone), PMSF (phenylmethanesulfonyl fluoride), benzamidine, soybean trypsin inhibitor, and ovomucoid.