Fig. 2: Epitope binning of WRAIR NTD and RBD-targeted mAbs against variants of concern.

Epitope binning of a NTD-directed or b RBD-directed mAbs as measured through a BLI-based competition assay. Values are the percentage of residual binding of the indicated WRAIR second antibody after saturation of the antigen (NTD or RBD subdomain) with a representative first antibody (NTD: Group A: WRAIR-2025, Group B: WRAIR-2137, Group C: WRAIR-2054) (RBD: Group A: WRAIR-2125, Group B: WRAIR-2063, Group C: WRAIR-2151). Competition groups are indicated by boxes in shades of brown (NTD) or green/purple (RBD). (Right) Closed S trimer (PDB 6ZGE) with epitopes of the NTD-targeted mAb competition groups indicated in tan, light brown, and dark brown. Each protomer of the S trimer is colored cyan, light grey, or dark grey. (Inset a, center) The NTD is shown in surface representation, with residues identified for competition shown in respective shades of brown. Residue deletions observed in Omicron subvariants are highlighted in red. c Mapping of RBD A and B mAbs using alanine mutagenesis across the spike glycoprotein. d Residues identified by e viral escape assays are highlighted to show the targeted epitope of Group A and Group B RBD WRAIR mAbs. Residues of each group are shown in sphere representation on the SARS-CoV-2 RBD. Residues targeted by more than one antibody are highlighted. Source data are provided as a Source Data file.