The accumulation of MO and DC in the atheroma and the relative depletion in the circulation [24] could stimulate both T cell recruitment and activation and may facilitate the release of chemokines, cytokines and other inflammatory mediators which are involved in the development and Ulixertinib progression of HIV-associated atherosclerosis. Targeting CCR5 by MVC could have a double therapeutic effect in HIV-associated atherosclosis:
blocking HIV entry into heart tissue via CCR5 and down-regulation of the accumulation of inflammatory cells in the atheroma. Moreover, the down-regulation of MCP-1-mediated chemotaxis induced by MVC could play a beneficial role in preventing the spread of HIV to the brain. It is also known that both subsets of circulating myeloid DC (mDC) and plasmacytoid DC (pDC) are defective in HIV infection, especially because of homing in lymphoid organ and tissue [25,26]. After exposure to virions and HIV-infected cells, mDC and pDC up-regulate both tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and activation and migration markers, such as CD83 and CCR7, and acquire a killer-cytotoxic activity [27,28]. These cells down-regulate CXCR4 and CCR5 and become less susceptible to HIV infection; however, they are more active as proinflammatory Adriamycin purchase cells by inducing apoptosis in infected
and uninfected CD4 T cells and by producing cytokines such as interferon (IFN)-α and TNF-α. Our experiments suggest that MCV could inhibit Inositol monophosphatase 1 chemotaxis, especially on these activated DC which are usually present during HIV infection. The anti-chemotactic activity of CCR5 antagonist could have also potential therapeutic implications for
the management of inflammatory conditions other than HIV. The proposed mechanism of CCR5 antagonists in the treatment of rheumatoid arthritis involves inhibition of cell migration, a key pathway in the inflammatory process of the disease. In a mouse model of experimental autoimmune myocarditis (EAM) CCR5 was found to be important in the induction of the disease, and inhibition of CCR5 with monoclonal antibody reduced the severity of myocarditis significantly [29]. A critical issue associated with the block of cellular migration induced by CCR5 antagonist is a potential risk for treated patients of developing infectious complications. In effect, the reduced migratory capacity of MO and DC after pharmacological inhibition of CCR5 could impair the innate immune response against pathogens by blocking APC accumulation and activation at sites of microbial or antigenic challenge. Subjects homozygous for CCR5Δ32 who do not express CCR5 have a higher susceptibility to some infections, such as West Nile virus [30].