FIGURE 2.

Gallic acid inhibits SP-mediated enhancement of HIV infection (A) without compromising cellular viability (B). Gallic acid (0.5 mm) or the equivalent amount of DMSO was incubated with the indicated concentration of SP for 2 h, added to the CCR5-tropic HIV-1 strain 81A, and diluted 15-fold upon the addition to TZM-bl cells. Infection levels were assessed 3 days later by quantitating β-galactosidase activity (with signal from uninfected cells subtracted). Viability was assessed by cellular ATP levels (by CellTiter-Glo®). Averaged values and S.D. values of triplicate experiments are shown as solid bars, whereas the results of individual measurements are shown as an overlay in hatched red bars. *, p < 0.05, Student's t test. n.s., not significant.