FIG. 9.

Virion-associated Vpr enhances effector caspase 3/7 activity in human activated PBMCs treated with anti-Fas antibody. Human activated PBMCs from donors 1 (A) and 2 (B) were mock infected or infected with Vpr(+)^trans or Vpr(−) viruses with equivalent numbers of infectious units. Forty-seven hours postinfection, the cells were treated with 2.5 μg/ml of the Fas CH11 antibody for 1 and 3 h. Caspase 3/7 activity was measured for each sample at 1 and 3 h post-CH11 antibody treatment (corresponding to 48 and 50 h postinfection). Blank values were subtracted, and the increase in activity was calculated based on activity measured from mock-infected cells. The black and gray bars represent caspase 3/7 activities at 48 and 50 h postinfection, respectively. The results are shown as means ± standard deviations.