Fig. 7: Biophysical and genetic correlates for best-in-class FP-directed antibody neutralization.

A Rare mutations identified through gene-specific substitution profiles (GSSPs) critical for the recognition of FP and HIV−1 Env trimer. GSSPs for the VRC34.01_Combo1 heavy chain IGHV1-2 gene are shown. Mutations identified in yeast display were highlighted with cyan background. A substitution frequency <0.5% was defined as a rare mutation and colored with a red square. CDR1 and CDR2 were shown with green and blue boxes, respectively. B Binding of optimized antibodies to His-tagged FP Ala/Gly mutants. Binding of alanine (gray bars) and glycine (white bars) mutants within FP, normalized by binding to the wild-type sequence, are shown, with FP amino acids on the y-axis. Experiments were performed in triplicate (n = 3 independent experiments), error bars indicate the mean with SD plotted for each residue position in the overlaid scatter dot plots. C ITC-derived affinity to diverse FP sequences for various antibody variants. D Residue-Residue Pair Energy Analysis by 100 ns Molecular Dynamics Simulation to understand the roles of E2K, T59F, and A33P mutations in improved neutralization performance. Mean is represented as red dashed lines, and red arrows show the energy difference between mutants and the VRC34.01 (WT) antibody. Gray dashed lines represent VRC34.01 (WT) performance for comparison.