FIG. 9.

Pooled HIV-positive human sera potently neutralize FS-containing envelopes. All envelope constructs were tested for neutralization with pooled HIV-1-positive human sera in the context of a fusion assay as described in the legend to Fig. 7. The percent inhibition obtained on cells expressing either CD4 and CXCR4 (A) or CD4 and CCR5 (B) is shown. The data are compiled from three experiments done in triplicate; standard errors of the mean are shown. Asterisks indicate statistical significance (t test; two-tailed, assuming unequal variances; P < 0.05). wt, wild type; nhs, normal human serum.