FIG. 6.

Effect of CsA on HIV-1 infection of syncytia between 293T cells. 293T cells were transfected with control (A) and M-PMV Env (B) plasmids. Twenty-four hours posttransfection, 293T cultures were labeled with DDAO and cocultured with an equal number of untransfected 293T cells labeled with CMTMR. After another 24 h, cultures were challenged with wild-type (WT) or mutant (A92E and G94D) HIV-1-GFP reporter virions in the presence or absence of 5 μM CsA. Two days later, cultures were analyzed by flow cytometry for GFP, DDAO, and CMTMR. (A) Infectivity frequency of unfused 293T cells (293T-293T). In these samples, no gating was applied to discriminate DDAO or CMTMR. (B) Infection frequency of syncytia positive for both fluorescence dyes (293T/Env-293T). The results shown are representative of at least two independent experiments.