Figure 1.

SARS-CoV-2 antibody responses to D614G and Omicron subvariants following monovalent booster, bivalent booster, or breakthrough infection

(A) EC₅₀ titers of binding antibodies in the serum samples from participants who received four doses of a monovalent mRNA vaccine (4-dose monovalent), three doses of a monovalent mRNA vaccine followed by one dose of a bivalent vaccine (3-dose monovalent + bivalent), and experienced BA.5 (BA.5 breakthrough) or BQ (BQ breakthrough) breakthrough infections after two to four doses of vaccine.

(B) ID₅₀ titers of neutralizing antibodies in the serum samples from “4-dose monovalent,” “3-dose monovalent + bivalent,” “BA.5 breakthrough,” and “BQ breakthrough” cohorts against D614G and Omicron subvariants. Breakthrough serum samples were separated into two sub-groups using two distinct symbols. Square symbols indicate samples from individuals who received three doses of monovalent vaccines followed by a breakthrough infection. Round symbols indicate samples from individuals who received four or five doses of monovalent vaccines and subsequently had a breakthrough infection. dpv, days post last vaccination; dpi, days post infection. The numbers in parentheses represent the mean days post last vaccination (dpv) or the mean days post infection (dpi).

(C) Serum-neutralizing ID₅₀ titers against XBB.1.5, XBB.1.16, and XBB.1.5 carrying the individual spike mutations found in XBB.1.16. Values above symbols indicate the geometric mean EC₅₀ or IC₅₀ titers for each cohort. The neutralization assay limit of detection (LOD) is 50 (dotted line), and the number of samples below the LOD is denoted above the x axis. Comparisons were made against “3-dose monovalent + bivalent” cohort (A) or XBB.1.5 (B and C) by Mann-Whitney tests. ns, not significant; ∗p < 0.05; ∗∗p < 0.01; ∗∗∗p < 0.001; ∗∗∗∗p < 0.0001. Sample sizes (n) are shown in (B). See also Tables S1 and S2.