FIG. 5.
Effect of the combination of lactacystin and BFLA-1 on HIV-1 infectivity. P4-R5 Magi cells were incubated for 1 h with HIV-1SF2, HIV-1NL4-3, or HIV-1SF162 in the absence or presence of either 100 nM BFLA-1, 20 μM lactacystin, or both. Shown are the averages of triplicate infections with fold increases indicated above each column. Note that the increased infectivity in the presence of the combination of inhibitors is additive for HIV-1NL4-3 and HIV-1SF162 but synergistic for HIV-1SF2. The lower absolute infectivity of the different viruses when compared to results shown in Fig. 1, 2, and 3 is due to the shorter incubation time used for infection (1 h vs. 16 to 18 h). β-gal, β-galactosidase.