Fig. 4.

Single-cycle infection of Ptm lymphocytes with luciferase pseudoviruses bearing Q23-17 Env mutants. The y axis shows relative light units (RLUs) in cells infected with the virus variants indicated on the x axis. The dashed line represents background RLU levels observed in cells infected with Env(−) pseudovirus. Error bars represent the standard deviations obtained from triplicate wells. wt, wild-type Q23-17 envelope; ND, not determined due to insufficient titer. The results are representative of at least two independent experiments.