FIG 8.

Competition evaluation. Dose-dependent binding competitions between sera and IgG#33 were performed. FACS analyses were performed using IgG#33 combined with serial dilutions (1:100 to 1:800) of both neutralizing (NT) serum (A) and nonneutralizing (non-NT) (B) serum to evaluate the possible competitive binding of antibodies to gD1-transfected cells. As shown by the graphs, no competition resulted even with the lower serum dilution tested. NT (C) and PEI (D) assays next were performed on Vero E6 cells with NT serum and a non-NT serum supplemented by IgG#33 against both HSV-1 and -2 infections. In NT assays, IgG#33 was used at its 50% inhibitory concentration (1.092 μg/ml against HSV-1 and 0.731 μg/ml against HSV-2 tested isolates), while in PEI assays it was used at 25 μg/ml and 100 μg/ml against HSV-1 and -2, respectively. Sera were used at 1:100 dilution, and the MAb alone control is indicated by white columns. Mean values ± SD are reported for each experimental condition (*, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001).