Figure 1

Extracellular ATP reduces HIV-1 transfer from iDCs to autologous CD4⁺ T cells. iDCs were initially pulsed with R5-tropic NL4-3Balenv either produced upon transient transfection of 293T cells (A) or following acute infection of CD4⁺ T cells (B). In some experiments, iDCs were pulsed with X4-tropic viruses consisting of the laboratory variant NL4-3 produced upon transfection of 293T cells (C) or the clinical strain 92HT599 amplified in PBMCs (D). Pulsing was performed in absence or presence of the indicated concentrations of ATP for 60 min at 37°C. Next, iDCs were washed extensively to remove input virus and excess ATP and co-cultured with autologous CD4⁺ T cells at a 1:3 ratio. Virus production was assessed by measuring the cell-free p24 contents at the listed time points. Virus production at day 2 following initiation of the co-culture is depicted in the small inserts (upper left part of each panel). The data shown represent the means ± standard deviations of triplicate samples and are representative of four independent experiments for panels A, C and D, and three for panel B. Statistical analysis was performed on the results from all experiments. Asterisks denote statistically significant data (*, P < 0.05; **, P < 0.01).