Rho inhibitor blocks migration of HIV-1–infected monocytes. (A) Cells were infected with HIV-1_ADA Eight and 24 hours after infection, and cells were lysed for viral DNA analysis. Primers that specifically amplified early and late products of reverse transcription were used. The PCR-amplified products were quantified on a PhosphorImager after hybridization. A representative experiment is shown. (B) HIV-1–infected (18 hours after infection) or uninfected monocytes (105) were applied to BBB constructs, and their migration was studied in response to MCP-1 (5 ng/mL in the bottom chamber). Pretreatment of the top-chamber BMVECs with C botulinum C3 transferase (24 hours; 10 μg/mL) diminished migration of infected and uninfected cells by 40% and 25%, respectively, across the BBB. Results were normalized to migration of uninfected monocytes without MCP-1 (a value of 100%). Values represent the mean of quadruplicate determinations ± SEM. Results of 1 representative experiment are shown.