Proliferation, but not interleukin 2 production, of Gag-specific CD8+ T cells is associated with low HIV viremia and high CD4 counts in HIV-1-infected Chinese individuals.

BACKGROUND: To control HIV globally, a comprehensive understanding of host immunity to HIV in different human populations is needed. Relatively, little is known on the quantity and quality of HIV-specific T-cell responses in Chinese patients. METHODS: We quantified HIV Gag-specific CD8+ and CD4+ T cells that are capable of producing interferon (IFN)-gamma and interleukin 2 and assessed their proliferative capacity in a cohort of 53 antiretroviral-naive chronically HIV-1-infected Chinese patients. RESULTS: The proliferation of Gag-specific CD8+ T cells, but not their IFN-gamma or interleukin 2 production, was inversely proportional to HIV viral load and directly proportional to CD4+ T-cell counts. Gag-specific CD8+ T-cell proliferation was proportionate to the frequency of IFN-gamma-secreting CD8+ T cells. Such correlations, however, did not exist for Gag-specific CD4 T cells. CONCLUSIONS: These results suggest that good quality and large quantities of HIV Gag-specific T-cell responses are associated with virologic control in HIV-1-infected Chinese patients. We infer that protective T-cell vaccines tested in other populations should also provide benefit to the Chinese population.