FIG 4.

Subset of growth-enhanced mutants are more sensitive to CD81-LEL and NMAb inhibition. Parental or mutant viruses were preincubated with a dilution series of CD81-LEL (A) or anti-E2 antibody H77.39 (B) or HC84.26 (C) for 1 h at 37°C and then added to Huh7.5 cells. Infection was quantified 72 h later by FFA. EC₅₀ were determined by nonlinear regression analysis. The panels on the left are representative dose-response curves for parental virus and the mutants. The fold decrease in EC₅₀ for the antibody treatment of mutant relative to parental virus is plotted on the right. Asterisks indicate differences that are statistically significant (*, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001; ns, not significant). Error bars represent SEM. The results are the averages from three independent experiments performed in triplicate or quadruplicate.