Figure 6

lipid exchange and syncytia formation during cell-to-cell fusion experiments. HeLa-Env/LAI and target cells were labeled with DiO and DiI, respectively. Co-cultures of labeled cells were performed in the presence of PBS (control), Rgp41A buffer, Rgp41A or T-20. After 6 h, lipid exchange between both types of cells was evaluated by flow cytometry analysis. In parallel, an X-Gal assay was performed to estimate the fusion efficiency between Env- and CD4-expressing cells in the presence or absence of inhibitors. Indicated percentages correspond to the proportion of double-positive gated cells. -: absence of syncytia, +/-: presence of small syncytia, +: presence of many large syncytia.