Fig. 4: Role of S in the immune resistance of Omicron.

a, ND₅₀ values for WA1, Omi-S and Omicron in sera from individuals who received two shots of Moderna (donors 1–12) or Pfizer (donors 13–24) vaccine (further details of sera are provided in Extended Data Table 1; individual curves are shown in Extended Data Fig. 10). b, Trajectories of ND₅₀ values against WA1, Omi-S and Omicron (the data from a are plotted). The fold change in ND₅₀ values is indicated (n = 24 serum samples). c–f, Schematic of the chimeric (left; c,d) and mutant (left; e,f) viruses. The amino acid numbering for WA1 mutants in e is based on the WA1 S sequence, whereas the numbering for Omicron mutants in f is based on the Omicron S sequence. Six of the 24 sera (3 from Moderna and 3 from Pfizer) were tested. Each serum sample is represented by a dot of specific colour. The data are plotted as the fold change of the parental virus. Statistical significance was determined using a two-tailed, unpaired t-test with Welch’s correction. *P < 0.05, **P < 0.01, ***P < 0.001 and ****P < 0.0001; NS, not significant.