Guinea Pig NAbs Target the C3 and V4 Region on BG505 SOSIP.664
(A) Cross-competition of guinea pig NAbs with epitope well-defined bNAbs for binding to BG505 SOSIP.664 trimer. Data were generated in duplication, with selected reactions repeated at least twice.
(B) 3D EM reconstruction of CP506 Fab/BG505 SOSIP.664 complex. The crystal structure of BG505 SOSIP.664 trimer (PDB: 4TVP), displayed in pink ribbons, is docked into the trimer EM density. Five N-linked glycans at the contact interface are highlighted in green, labeled with respective residue numbers.
(C) Comparison of the mode of CP506 binding to BG505 SOSIP.664 Env trimer with bNAbs VRC01 (upper) (EMDB: EMD-6193) and 3BC315 (lower) (EMDB: EMD-3067), which recognizes the CD4bs and gp120/gp41 interface of Env, respectively.
(D) Competition ELISA assay using biotin-labeled CP506 Fab and 3BC315 Fab as analytes confirms competition between CP506 lineage NAbs and bNAbs, including VRC01 and 3BC315. Data were generated in duplication, with reactions of 3BC315 Fab repeated twice.