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Numerous forms of Bartonellosis are caused by Bartonella henselae as well as Cat Scratch Disease & Bacillary Angiomatosis. It has been found that up to 95% of patients with Cat Scratch Disease show antibodies against Bartonella henselae antigens.

Highly immunoreactive proteins which are produced by the Bartonella henselae are the most important antigens used for the diagnosis of Cat Scratch Disease.

Bartonella henselae of outer membrane protein p26 has an important nucleotide identity with orthologs in Bartonella spp, Brucella spp in addition to more than a few plant-associated bacteria.

A main factor of pathogenic Yersinia enterocolitica strains is a plasmid-encoded type 3 secretion system, through which Yersinia outer proteins (Yops) are injected into the host cell. Yop E is a GTPase activation protein which controls pore formation by activating small Rho GTPase, causing inhibition of actin polymerization.

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.

MX2 is a member of 2 protein families: the dynamin family and the large GTPases family. MX2 has a cytoplasmic and nuclear structure which is found in a granular pattern in the heterochromatin region under the nuclear envelope. The nuclear form has a NLS (nuclear localization signal) at the amino terminal end however it is missing in the cytoplasmic form as a result of the use of a different translation start codon. MX2 is upregulated by IFN-a, but unlike myxovirus resistance protein 1 has no antiviral activity.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

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.

Since April 2012, cases of the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) have been identified in various countries. Coronaviruses are the cause of the common cold, SARS (severe acute respiratory syndrome) and other severe illnesses with high mortality rates, all are classified into coronavirus family. MERS-CoV is a new type of SARS found in the coronavirus family causing severe pneumonia with sudden and serious respiratory illness with high mortality rates as well. Since January 27th 2015, the WHO has reported 956 human cases, including 351 deaths. More cases of the new coronavirus strain are expected. Like in other coronaviruses, large surface spike glycoprotein is a central structural protein of this virus; it is located above the virion surface to bind and enter into the target cell. Spike protein has 2 domains- S1 and S2. The S1 domain is responsible for cellular tropism and interaction with target cell, while the S2 domain is responsible for membrane fusion. The C-terminal of S1 domain contains a receptor binding domain, and is also a potential target for vaccine development and an antigen for diagnosis.

C1q is the first component of the classical pathway of complement activation. C1q along with the enzymatically active components C1r and C1s forms the C1 complex. When C1 binds to immunoglobulins in the form of immune complexes, it leads to activation of C1r and C1s proteases and a further activates the classical pathway of complement. C1q is a glycoprotein that belongs to the collectin family, having a molecular weight of about 410-462 kDa. C1q is a hexamer composed of globular heads attached to collagen-like triple-helix tails. The globular heads of C1q exclusively bind to the CH2 domain of IgG molecules or the CH3 domain of IgM. Each heavy chain of the immunoglobulin molecule contains a single binding site for C1q. Given that C1q must bind to no less than two heavy chains in order to alter its conformation and activate C1r and C1s, its activation follows only after binding to immunoglobulins in the form of immune complexes bound to multivalent antigens. C1q’s main physiological role is in the clearance of immune complexes and apoptotic bodies from the organism. Interruption of this process may lead to development of autoimmunity. Individuals with genetic deficiencies of C1q or other components of the classical pathway are at risk to develop SLE. C1q specifically binds to apoptotic bodies of human keratinocytes, vascular endothelial cells and lymphocytes. Complement components C1q and bound C3 mediate the clearance of apoptotic bodies. Hence, C1q may advance the clearance of autoantigens, avoiding stimulation of the immune system. Nonetheless, an extended exposition of the immune system to the neoepitope exposed on C1q molecules bound to immune complexes or apoptotic bodies could ultimately lead to an autoimmune response against C1q itself and to an altered complement function. C1q deficiency may also lead to disruption of the negative selection of autoreactive B cells. C1q along with other specific recognition proteins bind to the highly conserved lupus antigens (dsDNA and nuclear proteins) and activate the complement system. Autoantibodies against C1q (anti-C1q) are found in a number of autoimmune and infectious diseases like glomerulonephritis (GN) and lupus erythematosus (SLE), these antibodies are significant in clinical practice due to their negative predictive value.

Dengue fever is affected by 1 of 4 closely linked virus serotypes of the genus Flavivirus, family Flaviviridae. One might have dengue fever infected by the different serotype virus after the primary infection. Detection of particular antibodies to dengue viruses is used for the diagnosis in clinic. Recently, lateral flow rapid test products have become a most suitable and known method in the clinical diagnosis. Though, there is difficulty for manufacturers to have the dengue antigens with a whole coverage for Dengue IgG & IgM recognition for all 4 serotype infections as well as with colloid gold binding ability. 8 dengue antigens have been established for the lateral flow products which are well defined for their coverage of dengue IgG & IgM recognition. The researcher can select the products below based on their own specific application.

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.

Shiga-like toxin (verotoxin) is a toxin produced by some strains of Escherichia coli. Shiga-like toxin is named for its similarity to the AB5-type Shiga toxin produced by the bacteria Shigella dysenteriae. There are two known types-SLT1 and SLT2. The Shiga-like toxin is linked with hemolytic-uremic syndrome. Shiga-like toxin requires highly specific receptors on the cells'' surface in order to attach and enter the cell. Species such as cattle, swine, and deer which do not carry these receptors may harbor toxigenic bacteria without any ill effect, dropping them in their feces, from where they may be distributed to humans. Shiga Like Toxin-1 Subunit B has nontoxic action, it is the functional region which binds to the receptor. The Shiga Like Toxin-1 Subunit B can be useful in vaccine study, antibody test and other functional research.

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).

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 subsp. 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.

Receptors across the cell membrane interact with some viral glycoproteins therefor enabling HSV to enter the host cell. The HSV enter through pores created by the binding of particular receptors across the cell membrane with the virus's coating envelope, following by a fusion of the HSV and the host cell. HSV enters the host cell through the same mechanism and stages as other viruses do. Initially, matching receptors across the virus's envelope and host cell's membrane interacts and bring the two together. During the transitional stage, begins fusion between the host cell and virus (hemifusion state). The closing stage happens when a steady pore was made; through these pores the virus's particles enter the cell.

Entry of HSV into the host cell involves interactions of several viral glycoproteins with cell surface receptors. The virus particle is covered by an envelope which, when bound to specific receptors on the cell surface, will fuse with the cell membrane and create an opening, or pore, through which the virus enters the host cell. The sequential stages of HSV entry are analagous to those of other viruses. At first, complementary receptors on the virus and cell surface bring the two membranes into proximity. In an intermediate state, the two membranes begin to merge, forming a hemifusion state. Finally, a stable entry pore is formed through which the viral envelope contents are introduced to the host cell.

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.

Angiopoietins belong to the vascular endothelial growth factor family and the only known growth factors largely specific for vascular endothelium. Angiopoietins-1, 2 and 4 partake in the formation of blood vessels. ANGPTL2 displays angiogenic effects. Angiopoietin-like Protein 2 (ANGPTL2) is an anti-diabetic factor. ANGPTL2 induces sprouting in endothelial cells through an autocrine and paracrine action. ANGPTL2 increases insulin sensitivity in adipocytes. In addition, ANGPTL2 is a mediator of chronic adipose tissue inflammation. ANGPTL2 is widely expressed in the heart, small intestine, spleen and stomach. ANGPTL2 is also found in lower levels in the colon, ovary, adrenal gland, skeletal muscle and in prostate.

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 subsp. 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.

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.

ANGPT1 is an angiogenic factor which intervenes in blood vessel maturation and takes part in endothelial development. ANGPT1 is a secreted ligand for Tie-2, a cell surface receptor tyrosine kinase expressed in endothelial and hemopoietic cells. The glycosylated ANGPT1 protein has a coiled-coil region in the amino terminus and a fibrinogen-like domain at the carboxy terminus.

Chemokine (C-X-C motif) ligand (CXCL7) is a small cytokine belonging to the CXC chemokine family. It is a protein that is released in large amounts from platelets following their activation. It stimulates various processes including mitogenesis, synthesis of extracellular matrix, glucose metabolism and synthesis of plasminogen activator.

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.

Babesiosis is a disease caused by apicomplexan parasites of the Babesia genus. The Babesia microti life cycle involves 2 hosts, which include a rodent, mainly the white-footed mouse (Peromyscus leucopus) and a tick in the Ixodes genus. During a blood meal, a Babesia-infected tick introduces sporozoites into the mouse host. Sporozoites pass into the erythrocytes and undergo asexual reproduction (budding). In the blood, some parasites differentiate into male and female gametes, though these cannot be distinguished by light microscopy. The definitive host is the tick. Once ingested by an proper tick, gametes unite and undergo a sporogonic cycle resulting in sporozoites. Transovarial transmission (aka vertical or hereditary transmission) has been detected for "large" Babesia species but not for the "small" Babesia, such as B. microti. Humans enter the cycle when bitten by the infected ticks. Thus during a blood meal, a Babesia-infected tick introduces sporozoites into the human host. Sporozoites then enter erythrocytes and undergo asexual replication (budding). Multiplication of the blood-stage parasites is responsible for the clinical manifestations of the disease. Humans typically are dead-end hosts. However, human-to-human transmission is well acknowledged to occur via contaminated blood transfusions.