Binding and neutralization activities of PGT121GM and 10-1074GM mutant antibodies. (A) SPR sensorgrams showing the binding of PGT121GM (light green) and 10-1074GM (light blue) to YU-2 gp120 or gp140. (B) Bar graphs comparing apparent KD values for the binding of 10-1074, PGT121, PGT121GM, and 10-1074GM antibodies to gp120 and gp140. Error bars indicate the SEM of KD values obtained from three independent experiments. Fold differences between KD values of wild-type vs. glycomutant antibodies are indicated. (C) Bar graphs comparing binding of glycans (SI Appendix, Fig. S6A) by PGT121 and 10-1074 with mutant antibodies (PGT121GM and 10-1074GM). Numerical scores of binding are measured as fluorescence intensity (means at duplicate spots) for probes arrayed at 5 fmol/spot. (D) Graphs comparing IC50 values for neutralization of selected viruses by PGT121, 10-1074, PGT121GM, and 10-1074GM in the TZM-bl assay. Viral strains are listed with PNGSs at the indicated gp120 positions (those near Asn332gp120) color coded: dark gray, a PNGS; white, not a PNGS. From the 2012 Los Alamos filtered web alignment of ∼2,865 gp120 sequences, the frequencies of PNGSs at these positions are 295 (58.3%), 301 (91.7%), 332 (73.0%), 334 (20.4%), 386 (86.7%), 392 (79.4%), 396 (25.7%), 406 (5.5%), 446 (7.6%), and 448 (85.6%). Gray shading indicates PGT121-sensitive viruses that were not neutralized by PGT121GM and a 10-1074–resistant strain that was neutralized by 10-1074GM. (E) Coverage graph comparing the neutralization breadth and potencies of PGT121, PGT121GM, 10-1074, and 10–1074GM antibodies in the TZM-bl assay against a panel of 40 viruses.