Viral chemokines

Models also can assist in experimental design and the determination of the limits of experimental systems. For example, it is known that three proteins mediate the interaction of HIV with cells namely, the chemokine receptor CCR5, the cellular protein CD4, and the viral coat protein gpl20. An extremely useful experimental system to study this interaction is one in which radioactive CD4, prebound to soluble gpl20, is allowed to bind to cellular receptor CCR5. This system can be used to screen for... 

Antiviral Drugs Viral Proteases Chemokine Receptors... 

The activation of DRF-3 through the TREF dependent pathway allows for chemokines such as RANTES to be produced. It also leads to the production of DFN-a and EFN-(3, which are involved in anti-viral immunity. The TREF pathway, activated by either TLR-3 or TLR-4, can also induce MHC class-II expression and costimulatory molecules, thus leading to T-cell activation. This provides an important link between innate and adaptive immunity. 

In addition to the role of chemokines/chemokine receptors in viral infection, transmission, and pathogenesis, chemokines also play important roles in cellular trafficking and survival pathways. The role of chemokines and their receptors are of particular importance in the development of neurologic complications of AIDS, involving mechanisms discussed in the following sections. 

Chemokines are small chemotactic cytokines that act as important messenger molecules between cells of the immune system. Chemokines produce their effects by activating a family of G-protein-coupled receptors. Chemokine receptors are all seven-transmembrane glycoproteins that are structurally related. They may be characterized into those that bind to specific ligands, or those that bind several chemokine ligands. There are also virally encoded (viral) chemokine receptors that represent shared receptors that have been transduced into the viral genome during evolutionary history (Premack and SchaU 1996). 

Berger EA, Murphy PM, Farber JM (1999) Chemokine receptors as HIV-1 coreceptors roles in viral entry, tropism, and disease. Annu Rev Immunol 17 657-700 Bernasconi S, Cinque P, Peii G, Sozzani S, Crociati A, Torri W, Vicenzi E, Vago L, Lazzarin A, Poli G, Mantovani A (1996) Selective elevation of monocyte chemotactic protein-1 in the cerebrospinal fluid of AIDS patients with cytomegalovirus encephalitis. J Infect Dis 174 1098-1101... 

Infection of macrophages and lymphocytes by HIV-1 can occur after binding of the viral envelope protein gpl20 to one of the several possible chemokine receptors... 

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