Role of natural killer cells in HIV pathogenesis.

Although the majority of research on immune cell recognition of HIV-infected cells has focused on CD8+ T cells with an eye towards vaccine development, innate immune recognition by natural killer (NK) cells has become a focus in recent years. Genetic and mechanistic data indicate that NK cells play a role during pathogenesis, and research on NK biology in the context of the broader immune response shows that NK cells are required to mount an effective antiviral response. HIV is able to escape cytotoxic T lymphocyte recognition by downmodulation of major histocompatibility complex class I receptors, which should enhance NK cytotoxicity against infected targets. However, the virus has evolved elaborate mechanisms to evade NK cell responses. Moreover, NK cell function as a whole is compromised through poorly understood mechanisms as a result of viremia. Further work on the role of NK cells during all stages of disease will further our understanding of the immune response against HIV.