T Lymphocytes in AIDS Patients With Tuberculosis

CD 4 + and CD 8 + T lymphocyte counts, naive and memory/effector CD 4 + T subpopulations, and the expression of CD 38 on CD 8 + T lymphocytes were evaluated in four groups: AIDS patients with tuberculosis (HIV/TB, n=14), HIV-1 infected patients (HIV, n=10), HIV-1 negative patients with tuberculosis (TB, n=20) and healthy controls (CTL, n=17). TB and HIV had fewer CD 4 + T cells than CTL, with the lowest values observed in TB/HIV (p<0.001). No difference between groups was observed in the percentage of naive and memory/effector subpopulations in CD 4 + T lymphocytes. TB (355 cells/μL) and HIV (517 cells/μL) had diverging effects on CD8 + T cell counts, with a marked depletion observed in HIV/TB (196 cells/μL). TB and HIV up-regulated CD38 expression on CD 8 + T cells, a finding also present in TB/HIV. While the decrease of CD 4 + T cell counts in HIV/TB may be attributed to HIV and tuberculosis, the decrease of CD 8 + T cell counts is likely to be due to tuberculosis.