Enhanced IFN-gamma production in vitro by CD8(+) T cells in hemophiliacs with AIDS as demonstrated on the single-cell level

We examined T cells from HIV-infected hemophiliacs under antiviral therapy, on the single-cell level, for cytokine production in vitro in response to stimulation. The percentage of IL-2-producing cells was markedly decreased among both CD3(+)CD8(-) and CD3(+)CD8(+) cells, while the proportion of IFN -gamma-producing cells was preserved among CD3(+)CD8(-) cells and increased among CD3(+)CD8(+) cells in HIV+ subjects, compared with HIV-uninfected co ntrols. The increase in IFN-gamma-producing CD8(+) cells was accounted for by the expansion of CD8(+)CD28(-) cells among total CD8(+) T cells and by t he higher percentage of IFN-gamma-expressing cells among both CD8(+)CD28(+) and CD8(+)CD28(-) cells in HIV+ individuals, compared with controls. The e nhanced IFN-gamma production in CD8(+) cells from individuals in the advanc ed phase of HIV infection might implicate the host's response to chronic vi ral infection or senescence of host CD8(+) cells. (C) 1999 Academic Press.