FIG. 3.

Conformationally authentic noninfectious HIV-1 virions partially activate and induce apoptosis in CD8⁺ T lymphocytes. Freshly isolated, unstimulated PBMC were either mock treated or treated with CEMX174/(T1) microvesicles (10 μg/ml), infectious or AT-2-inactivated HIV-1_{NL4-3/CEMX174/(T1)} (10 ng/ml p24^CA equivalents). On day 10, PBMC-T cells were analyzed for (A and E) CD25 expression, (B and F) Fas expression, (C and G) apoptosis, as detected by annexin V staining and (D and H) absolute number of CD4⁺ or CD8⁺ T lymphocytes by flow cytometry and trypan blue analysis. For absolute T-lymphocyte counts, error bars represent standard deviation of triplicate measurements.