FIG 5.

PIMi IV prevents reactivation of latent HIV-1 infection despite high levels of TNF-α-induced NF-κB activity. (A) CA5 T cells were stimulated with TNF-α (10 ng/ml) in the absence (control) or presence of PIMi IV (10 μM). Cells were harvested at the indicated time points, nuclear extracts were prepared, and NF-κB p50 and p65 activities were measured using TransAM assays. (B) Maximum initial NF-κB activation achieved in the absence or presence of PIMi IV (10 μM) at 1 h post TNF-α activation was determined in three independent experiments. The P values (Student's t test) describing the significance of possible differences between the stimulated control (C) conditions (TNF) and the PIMi IV-treated TNF-α-stimulated conditions (PIMi/TNF) are shown. (C) TNF-α-induced HIV-1 reactivation levels in CA5 T cells in the absence or presence of PIMi IV as used in the kinetic NF-κB activation experiments depicted in panel A. (D) In the absence or presence of PIMi IV, CA5 T cells were stimulated with TNF-α, and cells were harvested at the indicated time points. Western blotting was performed to determine IκB expression kinetics over 240 min. To ensure even loading of the lanes, membranes were stripped and probed for tubulin expression (shown for activated CA5 T cells treated with PIMi IV).