Phenotypic distribution of T cells of patients who have subsequently developed AIDS

In a previous study of asymptomatic homosexual men, we found that CD8+ T-cell levels were higher in homosexual men infected with the human immunodeficiency virus (HIV) than in uninfected homosexual men because of higher numbers of CD8+ T cells that do not express the Leu15 marker, a phenotype associated with cytotoxic function. Among infected men, there was a positive correlation between the number of CD8+Leu15- T cells and the number of CD4+ T cells. If CD4+ T-cell levels are taken as a measure of severity of HIV infection and immunodeficiency, these results suggested that higher CD8+Leu15- cells may represent a phenotypic profile associated with less severe infection or better control of infection. In the present study, we extend the analysis to include a group of men who progressed to AIDS but were studied well before the onset of AIDS, and we compare results of CD8 subset analyses with results of infected men who have not progressed to AIDS. Phenotypic subsets associated with helper, suppressor, cytotoxic, and natural killer cell function were determined by two-color immunofluorescence. The only phenotypic subset that distinguished men who progressed to AIDS from those who have not was lower numbers of CD4+ T cells in the former group. If CD8+Leu15- cell numbers (or other phenotypic subsets examined) reflect effective control of HIV infection, the relationship is not strong enough to be of prognostic or predictive value with respect to outcome of infection.