Host immunity cytokine regulation

It has been established that several DNA viruses secrete proteins that are able to intercept cytokines as a means to modulate the host immune response (94-96). Recently, it has been discovered that the murine gammaherpesvirus 68 M3 gene encodes a secreted 44-kD protein that binds a wide range of chemokines (97,98). The M3 protein binds chemokines from all four subfamilies of chemokines including murine macrophage inflammatory protein-la (MIP-la), IL-8, murine monocyte chemoattractant protein-1 (MCP-1), and human regulated... 

T Cell and Cytokine Regulation of Host Protective Immunity... 

T cell and cytokine regulation of enterocyte apoptosis may also be important in the expulsion of nematodes, in particular T. spiralis and T. muris, which inhabit an intracellular niche. Certainly an increase in the number of apoptotic cells within the epithelium is observed around the period of expulsion of T. muris in resistant mouse strains (D. Artis, C.S. Potten and R.K. Grencis, unpublished). Apoptosis of host enterocytes may dislodge the nematode or perhaps expose vital feeding organs to immune attack, and so enhance expulsion. Whether enterocyte apoptosis results from the burrowing action of the worms or a tissue repair mechanism, or is involved in expulsion, remains to be investigated. 

Defective IL-12 production is associated with increased susceptibility to infection (e.g., familial disseminated Mycobacterium avium complex infection, T. cruzi infection, and human visceral leishmaniasis), a finding that supports the critical role of this cytokine in host defense and in the regulation of the cellular immune responsed The loss of immune function following infection with HIV may resrdt from altered production of immunoregulatory cytokines, such as IL-10 and IL-12. It was suggested that monocytes from HIV-positive individuals secrete decreased amounts of IL-12, which may lead to the development of Th2 type of responses characterized by high IL-10 secretion and immune dysfunction/ ... 

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