Fig. 4.

Pseudovirus neutralization assay of pseudovirus with spike proteins of Wuhan wild-type (WT) or Omicron variant with serum samples from the MD and HD groups taken on days 57 (4 weeks after second dose) and 237 (4 weeks after the third dose). Blue and red symbols show individual titer values. Thick horizontal bars represent GMTs and associated error bars represent 95% confidence intervals. Fold differences between GMTs are shown numerically above the upper dotted line. Dotted lines indicate the starting dilution (20; lower dotted line) and the final dilution (2560; upper dotted line) for the assay, and all values below 20 are tabulated as 10. Statistical significance was calculated with Kruskal–Wallis test with corrected Dunn’s multiple comparisons test. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001