FIG. 5.

Neutralizing MAbs prevent the transmission of HIV-1 from infected DC to T cells. Purified blood (A) or skin (B) DC were exposed to HIV-1 BaL for 90 min and washed to remove free virus. MAbs were added 24 h later. After a 30-min incubation, CD3⁺ T cells were added to the culture. (A) MAb IgGb12 was used at 25 μg/ml. As a control, CD3⁺ cells from a known homozygous CCR5 (Δ/Δ) donor were also used. Transmission of infection from DC to T cells was dependent on CCR5 and could be blocked by neutralizing MAbs. wt, T cells wild type for the CCR5 gene. (B) MAbs were used at a concentration of 25 μg/ml.