FIG. 3.
Infectivity of mutant envelope glycoproteins. Mutant envelope glycoproteins were pseudotyped in an envelope-deficient HIV vector with a luciferase reporter gene as previously described (18). Relative infectivity was calculated by comparing the luciferase activity of mutant to wild-type virus × 100%. Results are an average of at least three independent experiments. Each error bar indicates 1 standard deviation.