NKT cells in HIV-1 infection.

Natural killer T (NKT) cells are a unique T cell population that have important immunoregulatory functions and have been shown to be involved in host immunity against a range of microorganisms. It also emerges that they might play a role in HIV-1 infection, and therefore be selectively depleted during the early stages of infection. Recent studies are reviewed regarding the dynamics of NKT depletion during HIV-1 infection and their recovery under highly active antiretroviral treatment (HAART). Possible mechanisms for these changes are proposed based on the recent developments in HIV pathogenesis. Further discussions are focused on HIV's disruption of NKT activation by downregulating CD1d expression on antigen presentation cells (APC). HIV-1 protein Nef is found to play the major role by interrupting the intracellular trafficking of nascent and recycling CD1d molecules.