FIG 3.

PIMi IV inhibits HIV-1 reactivation in latently HIV-1-infected primary T cells. (A) Latently HIV-1-infected cultured central memory T cells were prepared from primary naive T cells as previously described (7, 27). Active infection events were indicated by GFP fluorescence (Donor 1) or by p24 staining (Donor 2). Over low-level background infection (control), HIV-1 reactivation was triggered using a CD3/CD28 MAb combination. Cyclosporine (Cs) prevented and PIMi IV markedly inhibited CD3/CD28 MAb induced reactivation. The percentage of GFP-positive cells is indicated. (B) To test whether PIMi IV inhibits anti-CD3/CD28 MAb-mediated T cell activation, primary T cells were left untreated (control) or CD3/CD28 MAb stimulated in the absence or presence of 10 μM PIMi IV. T cell activation was determined as the induction of CD25/IL-2 receptor-α chain expression by flow cytometric analysis. The experiment is representative of results from a total of four healthy donors tested. α, anti; SSC, side scatter.