Fig. 4: Critical residues for AZD8895 and AZD1061 binding.
From: Genetic and structural basis for SARS-CoV-2 variant neutralization by a two-antibody cocktail
a, Logo plots of mutation escape fractions at RBD sites with strong escape for AZD8895 (left) or AZD1061 (right). Taller letters indicate greater escape. Mutations are coloured by the degree to which they reduced RBD binding to human ACE2. Data shown are the average of two independent escape experiments using two independent yeast libraries; correlations are shown in Extended Data Fig. 7b,c. Interactive plots can be found at https://jbloomlab.github.io/SARS-CoV-2-RBD_MAP_AZ_Abs/. b, Logo plots of mutation escape fractions that are accessible by single-nucleotide substitutions from the Wuhan-1 reference strain. Effect represented as in a. c, Mapping DMS escape mutations for AZD8895 onto the RBD surface. Blue, RBD site with the greatest cumulative antibody escape; white, no escape detected; grey, residues where deleterious effects on RBD expression prevented assessment. Heavy chain, cyan; light chain, magenta. Two replicates were performed with independent libraries, as described in a. Green, structurally defined AZD8895 footprint on RBD. d, Mapping DMS escape mutations for AZD1061 onto the RBD surface in the RBD–AZD1061 complex. Mutations that abrogated AZD1061 binding are displayed on the RBD structure using a heatmap as in c. Heavy chain, yellow; light chain, pink; green, structurally defined AZD1061 footprint on RBD. e, Table showing the results of the VSV-SARS-CoV-2 escape selection experiments. f, Table showing the results of the passage of SARS-CoV-2 in the presence of subneutralizing concentrations of mAbs. g, Scatter plot showing the DMS data from a, with the mutation escape fraction on the x axis and the effect on ACE2 binding on the y axis. Crosses, mutations accessible only by multi-nucleotide substitutions; circles, mutations accessible by single-nucleotide substitutions. The substitutions selected by AZD1061 in VSV-SARS-CoV-2 (K444R, K444E) or authentic SARS-CoV-2 (R346I) are denoted. h, Locations of mutations in VOCs/VOIs mapped onto the RBD/AZD8895/AZD1061 crystal structure. i, Neutralization (FRNT) against SARS-CoV-2 VOC/VOIs. Assays were performed in duplicate and repeated twice. Data are the mean of two independent experiments. Wash-B.1.351 refers to a chimeric recombinant virus with the WA1/2020 backbone expressing the B.1.351 (beta) S-gene; Wash-B.1.1.28 refers to a similar virus expressing the B.1.1.28/P1 (gamma) S-gene.
