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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.

Influenza-B virus is a genus in the virus family Orthomyxoviridae. The only species in this genus is called "Influenza B virus". Influenza B virus only infects humans and seals. This limited host range is apparently in contrast with those caused by the similar Influenza virus A as both mutate by both genetic drift and reassortment. Influenza-B virus evolves slower than A viruses and faster than C viruses. Influenza-B virus mutates at a rate 2-3 times lower than type A. However, influenza B mutates enough that lasting immunity is not possible. The Influenza B virus capsid is enveloped while its virion consists of a matrix protein + envelope + nucleoprotein complex + nucleocapsid, and a polymerase complex. Influenza B is sometimes spherical and sometimes filamentous. Its 500 or so surface projections are made of hemagglutinin and neuraminidase.
The Influenza B virus is 14648 nucleotides long and consists of eight segments of linear negative-sense, single-stranded RNA. The multipartite genome is encapsidated, each segment in a separate nucleocapsid, and the nucleocapsids are surrounded by one envelope.

CD86, also known as B7-2 or Cluster of Differentiation 86 is a protein necessary for T cell activation and survival, it is expressed on cells that are antigen-presenting cells and acts as costimulatory signals for T cells. CD86 is the ligand for CD28 (for autoregulation and intercellular association) and CTLA-4 (for attenuation of regulation and cellular disassociation), two different proteins.

CD47, functions in cell adhesions by performing as an adhesion receptor for THBS1 on platelets, furthermore CD47 plays a role in the modulation of integrins. In addition, CD47 takes a vital part in memory formation as well as synaptic plasticity in the hippocampus. Receptor for SIRPA avoids maturation of immature dendritic cells and inhibits cytokine production by mature dendritic cells. CD47 prevents premature elimination of red blood cells, and it is also implicated in membrane permeability changes induced following virus infection.

Trichomonas vaginalis, an anaerobic, flagellated protozoan parasite, is most dominant protozoan causing sexual transmitted disease. T. vaginalis induced vaginal tract infection occurs as multiple steps involving interactions between host macromolecules and protozoan virulent factor. Adhension protein P65 of T. vaginalis has a vital part in assisting the penetration into vaginal tract surface.

Treponema pallidum is a gram-negative spirochaete bacterium and is considered to be metabolically crippled. There are at least four known subspecies: T. pallidum pallidum, T. pallidum pertenue, T. pallidum carateum and T. pallidum endemicum. The helical structure of T. pallidum pallidum allows it to move in a corkscrew motion through viscous mediums such as mucus. Treponema pallidum sub sp. pallidum has one of the smallest bacterial genomes at 1.14 million base pairs (Mb) and has limited metabolic capabilities, reflecting its adaptation through genome reduction to the rich environment of mammalian tissue.

Human T-lymphotropic virus (HTLV) is a human, single-stranded RNA retrovirus that causes T-cell leukemia and T-cell lymphoma. The virus activates a subset of T-helper cellscalled Th1cells. The result is a proliferation of Th1 cells and overproduction of Th1 related cytokines (mainly IFN-gamma and TNF-alpha). Feedback mechanisms of these cytokines cause a suppression of the Th2 lymphocytes and a reduction of Th2 cytokine production (mainly IL-4, IL-5, IL-10 and IL-13). The end result is a reduction in the ability of the infected host to mount an adequate immune response to invading organisms that require a predominantly Th2 dependant response (these include parasitic infections and production of mucosal and humoral antibodies).

Caused by one of four closely related virus serotypes of the genus Flavivirus, family Flaviviridae, each serotype is sufficiently different that there is no cross-protection and epidemics caused by multiple serotypes (hyperendemicity) can occur. In cell culture experiments and mice Morpholino antisense oligos have shown specific activity against Dengue virus.

CD47, functions in cell adhesions by performing as an adhesion receptor for THBS1 on platelets, furthermore CD47 plays a role in the modulation of integrins. In addition, CD47 takes a vital part in memory formation as well as synaptic plasticity in the hippocampus. Receptor for SIRPA avoids maturation of immature dendritic cells and inhibits cytokine production by mature dendritic cells. CD47 prevents premature elimination of red blood cells, and it is also implicated in membrane permeability changes induced following virus infection.

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.

CD163 is an acute phase-regulated receptor which participates in the removal and endocytosis of hemoglobin/haptoglobin complexes by macrophages and thus keeps tissues from free hemoglobin-mediated oxidative damage. Furthermore, CD163 partakes in the uptake and recycling of iron, through endocytosis of hemoglobin/haptoglobin and ensuing breakdown of heme. In addition, CD163 binds hemoglobin/haptoglobin complexes in a calcium-dependent and pH-dependent way. CD163 demonstrates greater affinity for complexes of hemoglobin and multimeric haptoglobin of HP-1F phenotype than for complexes of hemoglobin and dimeric haptoglobin of HP-1S phenotype. Moreover, CD163 stimulates a cascade of intracellular signals which involves tyrosine kinase-dependent calcium recruitment, inositol triphosphate formation and secretion of IL-6 & CSF-1.

The Epstein-Barr virus (EBV), also called Human herpes virus 4 (HHV-4), is a virusof the herpes family(which includes Herpes simplex virusand Cytomegalovirus. On infecting the B-lymphocyte, the linear virus genome circularizes and the virus subsequently persists within the cell as an episome. The virus can execute several distinct programs of gene expressionwhich can be broadly categorized as being lytic cycle or latent cycle. The lytic cycleor productive infection results in staged expression of a host of viral proteinswith the ultimate objective of producing infectious virions. Formally, this phase of infection does not inevitably lead to lysis of the host cellas EBV virions are produced by budding from the infected cell. The latent cycle(lysogenic) programs are those that do not result in production of virions. A very limited, distinct set of viral proteins are produced during latent cycle infection. These include Epstein-Barr nuclear antigen(EBNA)-1, EBNA-2, EBNA-3A, EBNA-3B, EBNA-3C, EBNA-leader protein (EBNA-LP) and latent membrane proteins(LMP)-1, LMP-2A and LMP-2B and the Epstein-Barr encoded RNAs(EBERs).

Chemokine (C-C motif) ligand 7 (CCL7) is a small cytokine known as a chemokine that was previously called monocyte-specific chemokine 3 (MCP3). Due to CCL7 possessing two adjacent N-terminal cysteine residues in its mature protein, it is classified among the subfamily of chemokines known as CC chemokines. CCL7 specifically attracts monocytes, and regulates macrophage function. It is produced by certain tumor cell lines and by macrophages. This chemokine is located on chromosome 17 in humans, in a large cluster containing many other CC chemokines and is most closely related to CCL2(previously called MCP1).

Salmonella Typhi is a pathogen causing typhoid fever, affecting over 17 million people with approximately 600,000 deaths annually worldwide. If untreated, typhoid fever cases result in mortality rates ranging from 12-30%.

The Epstein-Barr virus (EBV), also called Human herpes virus 4 (HHV-4), is a virus of the herpes family (which includes Herpes simplex virus and Cytomegalovirus. On infecting the B-lymphocyte, the linear virus genome circularizes and the virus subsequently persists within the cell as an episome. The virus can execute several distinct programs of gene expression which can be broadly categorized as being lytic cycle or latent cycle. The lytic cycle or productive infection results in staged expression of a host of viral proteins with the ultimate objective of producing infectious virions. Formally, this phase of infection does not inevitably lead to lysis of the host cell as EBV virions are produced by budding from the infected cell. The latent cycle (lysogenic) programs are those that do not result in production of virions. A very limited, distinct set of viral proteins are produced during latent cycle infection. These include Epstein-Barr nuclear antigen (EBNA)-1, EBNA-2, EBNA-3A, EBNA-3B, EBNA-3C, EBNA-leader protein (EBNA-LP) and latent membrane proteins (LMP)-1, LMP-2A and LMP-2B and the Epstein-Barr encoded RNAs (EBERs).

CD28 co-stimulation is necessary for CD4 positive T-cell proliferation & survival, interleukin-2 production, and T-helper type-2 development. Human post-thymic regulatory T cells require CD28 co-stimulation to expand and maintain potent suppressive function in vivo. Apoptosis plays a key role in the age-related decline of CD28 expression and in immunosenescence.

CD83 is a single-pass type I membrane protein and part of the immunoglobulin superfamily of receptors. CD83 involves in the regulation of antigen presentation. A soluble form of CD83 can bind to dendritic cells and inhibit their maturation. There were 3 transcript variants encoding different isoforms for CD83.

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.

Interleukin-1b is produced by activated macrophages, IL-1 Beta stimulates thymocyte proliferation by inducing il-2 release, b-cell maturation and proliferation, and fibroblast growth factor activity. IL1B proteins are involved in the inflammatory response, being identified as endogenous pyrogens, and are reported to stimulate the release of prostaglandin from synovial cells.