The role of innate immunity and chronic immune activation in the immunopathogenesis of AIDS has been recently investigated by comparative studies of experimental, pathogenic SIV infection of Asian macaques and natural, nonpathogenic SIV infection of African nonhuman primates. These studies have shown that both pathogenic and nonpathogenic SIV infections are characterized by a robust innate immune response to the virus. However, this response is transient in natural hosts, but persistent in Asian macaques, thus suggesting that this downregulation of innate immunity may protect sooty mangabeys and AGMs from chronic immune activation and progression to AIDS. Importantly, it is hoped that further elucidation of the genes and molecular pathways involved in maintenance of a state of low immune activation in chronically SIV-infected sooty mangabeys and AGMs will identify targets for therapeutic interventions aimed at limiting or abrogating the aberrant immune activation that is associated with HIV infection in humans.
The authors would like to thank Michaela Müller-Trutwin, Rama Rao Amara, Sue-Fen Kwa and Ann Chahroudi for helpful discussion.
There are no conflicts of interest.
Papers of particular interest, published within the annual period of review, have been highlighted as:
Additional references related to this topic can also be found in the Current World Literature section in this issue (pp. 447–448).
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