Priming conditions shape breadth of neutralizing antibody responses to sarbecoviruses

Fig. 1. sVNT multiplex assay shows relative ACE2 binding affinity to determine the sarbecovirus antibody profile which correlates with plate and viral based assays. a The % antibody inhibition of ACE2 binding to RBD was determined for convalescent samples following SARS-CoV-2 infection from day 30–60 (n = 20 subjects), day 80–270 (n = 20 subjects), day 365 (n = 22 subjects), and represented as a heatmap (b). ^Omicron sVNT bead-based results, data following uses plate-based results. a Dotted line indicates 20% inhibition as a positive result based on limit of quantification, and data represented mean+/− stdev and individual samples shown, grey shading indicates SARS-CoV-1 clade. a, b Kruskal-Wallis multiple comparisons test, *p < 0.05. Spearman correlation analysis (r) analysis for (c) Ancestral wild type SARS-CoV-2 RBD plate-based sVNT versus SARS-CoV-2 infectious virus PRNT50, (d) bead based sVNT versus SARS-CoV-2 infectious virus PRNT50, and e wild type SARS-CoV-2 RBD plate-based sVNT versus bead based sVNT. f Bland Altman analysis of wild type SARS-CoV-2 RBD plate-based sVNT versus bead based sVNT results. f The red and green areas show the limits of agreement (Upper limit of…

Fig. 2. Prior priming by infection accentuates mRNA vaccine antibody profile to sarbecovirus RBD. The % antibody inhibition of ACE2 binding to RBD was determined for a uninfected subjects pre and 1 month post 2 dose vaccination with BNTb162b2 (B) or Coronavac (C) (n = 30 subjects). b COVID-19 infected 1 month post 1 dose vaccination with BNT162b2 (SARS2 + B) or Coronavac (SARS2 + C) (n = 20 subjects, prior infection 346+/−105 days before vaccination). c Hong Kong (HK) SARS-CoV-1 infected patients (SARS1) 1 month post 2 dose vaccination with BNT162b2 (SARS1 + B, n = 7 subjects) or Coronavac (SARS1 + C, n = 2 subjects). d Guangzhou (GZ) SARS-CoV-1 infected patients from 2018 (n = 10 subjects) and post 2 dose vaccination with Sinopharm (SARS1 + S) at 1 to 6 months post vaccination (1 M n = 6 subjects, 3 M n = 5 subjects, 6 M n = 2 subjects). e Heat map representation of % inhibition of 1 month post vaccination (from a–d). a–d Data represented mean+/− stdev and individual samples. a, c Significant differences in paired pre versus post vaccine responses within vaccine type by one-way Friedmans tests with Dunns multiple comparisons (coloured, within vaccine type). b, d one-way Kruskall Wallis…

Fig. 3. mRNA third dose vaccination regardless of priming increases antibody breadth. a The % antibody inhibition of ACE2 binding to RBD was determined for third dose vaccination after CC or BB prime for either B or C boost (each group n = 20 subjects) 1 month post third dose vaccination. b Heat map representation of % inhibition of 1 month post vaccination (from a). c Fold change of pre versus post booster vaccination (from a). a Data represented mean+/− stdev and individual samples. b Significant differences in paired pre versus post vaccine responses within vaccine type by one-way Friedmans tests with Dunns multiple comparisons. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001, ns not significant.

Fig. 4. Omicron infection in combination with vaccine priming broadens antibody response. The % antibody inhibition of ACE2 binding to RBD was determined for a BNT162b2 (n=10 subjects), Coronavac (n = 7 subjects), unvaccinated (n = 5 subjects) paired acute (day 0–5) and recovered (1–2 months after illness) patients for Omicron BA.2 infection. a Data represented mean+/− stdev and individual samples. a, b Significant differences in paired pre versus post vaccine responses within vaccine type by one-way Friedmans tests with Dunns multiple comparisons. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. Statistics shown for acute versus recovered (b), and ns between Coronavac and BNT162b2 Omicron recovered samples by Ordinary one-way Anova w Sidak’s multiple comparison test.

Fig. 5. Overview of antigen diversity versus magnitude of neutralizing antibody responses for SARS-CoV2 viruses and sarbecoviruses for different priming conditions. A 2-D representation of all samples tested (from Table 1) for antigenic diversity versus the average % inhibition of all RBDs for SARS-COV-2 and its VoC (a), and all sarbecoviruses tested (b) for different priming conditions (from Figs. 2–4). Data represents the group average (95% CI), non-overlapping confidence intervals indicate significantly different responses. Open circles represent baseline samples at pre vaccination, pre third dose vaccination or acute infection samples. Closed circles represent post vaccination or post infection samples at recovered (Rec) timepoints.