DCs promote infection of HS CD4⁺ cells. (A) Susceptibility of HS and control CD4⁺ clones to HIV replication. As a positive control for viral replication, 2 HS clones (L11 and N2) and 2 control clones with other antigenic specificities (3.8, 2.2) were activated with PHA and grown with IL-2. Cells were infected at a high moi (2 nM p24 for 3 × 10⁵ cells). Viral replication was monitored at the indicated days by measuring Gag-p24 production in culture supernatants. (B) HIV-exposed DCs promote efficient viral replication in HS clones. imDCs were exposed to HIV_NL-AD8 (0.2 nM p24 for 10⁶ cells), washed, and cocultured with HS L11 or N2 cells and with control 3.8 or 2.2 cells. Cells were grown in the absence of exogenous IL-2. As a control, the 4 clones were directly exposed to the same viral inputs and cultured without DCs, in the presence of IL-2. Two independent experiments are assembled: autologous DCs were used in the upper panels, and HLA-matched (HLA-DRβ^*04⁺) DCs were used in the lower panels. Viral replication was monitored by measuring p24 production in culture supernatants. Data are representative of 4 independent experiments.