a, Escape mutations in spike-expressing VSV passaged in
the presence of monoclonal antibody. Plot shows mutation effects on antibody
(x-axis) and ACE2 (y-axis) binding. b, Neutralization of SARS-CoV-2
variants by S2E12 (spike-pseudotyped VSV on Vero E6 cells), as in Fig. 2d. c, S2E12 breadth of
neutralization (spike-pseudotyped VSV on 293T-ACE2 cells). Points represent mean
of biological duplicates. d, Replicative fitness of S2E12 escape
mutations identified in (a) on Vero E6 cells. Points represent mean
and error bars standard error from triplicate experiments. e,f,
Structures of S2E12 Fab (e) and S2D106 Fab (f) bound
to SARS-CoV-2 RBD. RBD sites colored by escape (scale bar, center). The E484
side chain is included for visualization purposes only but was not included in
the final S2D106-bound structure due to weak density.
g,h, Integrative features of the structural
footprints (5 Å cutoff) of S2E12 (g) and S2D106
(h). Sites are ordered by the frequency of observed mutants
among SARS-CoV-2 sequences on GISAID. Heatmaps as in Fig. 2b. Logoplots as in Fig. 1c, but only showing amino acid mutations accessible via
single-nucleotide mutation from Wuhan-Hu-1 for comparison with (a).
Barplots illustrate frequency of SARS-CoV-2 mutants and their validated effects
on antibody neutralization (spike-pseudotyped VSV on Vero E6 cells). Red,
>10-fold increase in IC50 due to mutation.