FIGURE 4.

Effect of the specific inhibitors of HIV-1 Env-mediated membrane fusion on the progress of membrane fusion. Soluble CD4 (0.1 μm) or C34 (2 μm) was added at the different time points during co-culture. A certain time after co-cultivation, the RL activity was determined. The degree of inhibition is shown in percentages. A representative data of four independent experiments is shown. A, shown is the inhibition profile of the WT Env of HIV-1. The filled circle and square indicate the results of soluble CD4 and C34, respectively. B and C, shown is the effect of soluble CD4 (panel B) and C34 (panel C) for mutants. The results for GpA (blue open diamond) and VSV-G (red open triangle) replacement mutants are shown together with those for WT. The profile of WT is shown with a broken line.