Fig. 2. Mutationally guided molecular modeling of MAb362 binding to RBD.

a SARS-CoV-2 S1 was pre-incubated with MAb362 IgG (red circles) and IgA (blue squares) ranging from ~2 to 2000 nM. Both MAb362 isotypes demonstrated concentration-dependent inhibition of SARS-CoV-2 RBD binding to Vero E6 cells at concentrations >30 nM. Data are plotted as the mean ± s.d. from n = 3 independent experiments. b Mutational scanning was performed to better delineate the binding surface. Key residues were mutated and expressed as recombinant proteins. Identified critical residues (orange) were experimental confirmed by shifts in EC₅₀ values for MAb362 binding in ELISA relative to wild-type RBD (blue). EC₅₀ values calculated from n = 3 independent experiments. c Surface representation of the predicted molecular model of MAb362 SARS-CoV-2 RBD complex; the light chain of MAb362 (light yellow), the heavy chain (green), and the SARS-CoV-2 RBD (violet). d The predicted binding interface on SARS-CoV-2 RBD with MAb362. The residues identified by mutagenesis from b are labeled and colored according to influence degree; red represents strongest defects, orange for medium defects and yellow for subtle defects. Source data are provided as a Source Data file a, b.