FIG 2.

Ability of W69 variants to interact with CD4-binding site ligands. Comparable amounts of radiolabeled monomeric gp120 from WT and W69 variants were incubated with 5 μg/ml of CD4-Ig (A), VRC01 (B), VRC03 (C), VRC13 (D), VRC16 (E), and b12 (F) for 1 h at 37°C. The precipitates were washed, run on SDS-polyacrylamide gels, and analyzed by densitometry. All values shown here were evaluated by the ligand binding capacity of WT gp120 (set as 1). Data represent the averages ± standard deviations (SD) from at least three independent experiments. Statistical significance was tested using an unpaired two-tailed t test. Shown are P values with significant differences (*, P < 0.05; **, P < 0.01; ***, P < 0.001).