Figure 2.
Characterization of affinity of SARS-CoV-2 antibodies to WT, delta, and omicron RBD variants
(A) 2D scatter plot with integrated density contours. All quantifiable data points reflecting KA (in M−1) and IgG concentration values (in M) are plotted. 95% confidence intervals for each point are colored in light red. Triangles denote patients receiving the REGN-COV cocktail. RBD variants: WT (grey), delta (blue), omicron (yellow). Dotted lines represent the measurements of the same patient sample against different RBD variants.
(B) Bar graph displaying the percentages of quantifiable samples for WT (grey), delta (blue), and omicron (yellow) RBD variants. Comparisons were performed including all samples, samples excluding those treated with REGN-COV, and only those treated with REGN-COV. Fisher’s exact test displayed no significant differences, at α = 0.01.
(C and D) Boxplot analysis of KA values (C) and IgG concentrations (D) for WT, delta, and omicron RBD variants.
(E) To employ a combined score of binding affinity (KA) and IgG concentration, we utilized the product KA x IgG concentration. (C-E): Colors denote treatment with REGN-COV (red) or absence of treatment (blue). Kruskal-Wallis (KW) with post-hoc Wilcoxon rank sum test (WC) after Holm correction for multiple comparisons was used, with α = 0.01. None of the group-wise comparisons reached statistical significance.