Fig. 2: Longitudinal analysis of serum antibody titers, infection neutralization of Delta and Omicron variants of concern and antibody avidity following mRNA BNT162b2 vaccination.
a, Anti-spike S1 domain IgG titers in 274 sera from 62 convalescents, and 304 sera from 73 naive participants as binding arbitrary units (BAUs) per ml, convalescent ***P = 0.0004, naive pre-vaccination (pre) versus w2 after vaccination (vacc.) 1 ***P = 0.0002, w2 after vacc. 1 versus m4 after vacc. 2 *P = 0.0181, m4 after vacc. 2 versus w2 after vacc. 3 *P = 0.0123, convalescent m7 after vacc. 2 versus w2 vacc. 3 ***P = 0.0005, naive w2 after vacc. 1 versus m7 vacc. 2 ***P = 0.0003. b,c, Serum IC50 values for infection-neutralization capacity normalized to 107 viral RNA copies of SARS-CoV-2 VoCs Delta in 266 and 296 sera (b) and Omicron in 261 and 279 sera (c) from 62 convalescents and 73 naive individuals, respectively; convalescent w2 vacc. 1 versus m7 vacc. 2 *P = 0.0357, and versus w2 vacc. 3 **P = 0.0043, w2 vacc. 2 versus m4 vacc. 2 **P = 0.0049, naive pre versus m4 vacc. 2 *P = 0.0197, and versus m7 vacc. 2 *P = 0.0376, w2 vacc. 1 versus m4 vacc. 2 *P = 0.0236, and versus m7 vacc. 2 *P = 0.0043. d,e, Heat maps showing average fold changes in IC50 values for Delta (d) and Omicron (e) between the respective time points for convalescent and naive individuals. f,g, Ratios between infection-neutralization IC50 values and anti-spike S1 domain antibody titers for Delta in 263 and 295 sera; convalescent pre versus m4 vacc. 2 **P = 0.0030, versus m7 vacc. 2 **P = 0.0052, and versus w2 vacc. 3 ***P = 0.0005, w2 vacc. 2 versus m7 vacc. 2 ***P = 0.0003, and versus m7 vacc. 2 ***P = 0.0005, naive w2 vacc. 1 versus m7 vacc. 2 **P = 0.0027, and versus w2 vacc. 3 **P = 0.0032 (f); and for Omicron in 258 and 278 sera from 62 convalescents and 73 naive individuals; convalescent pre versus m4 vacc. 2 *P = 0.0340, naive w2 vacc. 2 versus m4 vacc. 2 **P = 0.0077, and versus m7 vacc. 2 **P = 0.0011 (g). h, IgG-type anti-spike avidity in 288 sera from 90 convalescents, and 150 sera from 47 naive individuals, convalescent pre versus m4 vacc. 2 *P = 0.0340, naive w2 vacc. 2 versus m4 vacc. 2 **P = 0.0077, and versus m7 vacc. 2 **P = 0.0011. a–c,h, Boxplots with median, bounds between upper and lower quartiles, and whiskers between the 10th and 90th percentiles, SARS-CoV-2 convalescents (orange) and naive participants (blue). a–c,f–h, Medians are indicated by lines and interquartile ranges (IQRs) by the error bars. Differences between time points analyzed for statistical significance using the Kruskal–Wallis test with Dunn’s multiple-testing correction; ****P < 0.0001. Connecting lines indicate statistically significant differences between groups. Absence of connecting lines or asterisks indicates absence of significance. Inf, after infection; m4, 4 months after vaccination; m5, 5 months after infection; m7, 7 months after vaccination; m8, 8 months after infection.
