Fig. 2: Humoral immune responses following NDV-PFS vaccination in hamsters.

Syrian hamsters were vaccinated intranasally with NDV-PFS. a WT SARS-CoV-2 spike protein-specific serum IgG endpoint titers 21 days following each vaccine dose. b WT SARS-CoV-2, Delta, and Omicron (BA.2) neutralization titers 21 days following each vaccine dose. c Neutralization titers against WT SARS-CoV-2, Delta, and Omicron (BA.2) 21 days following the second vaccine dose, with fold differences in mean titers shown. Reported are Log10 NT50 values. Significance was assessed using two-way ANOVA in (b) and Kruskal–Wallis test in (c). ***p = 0.004; ****p < 0.0001. n = 40 for day 21 and n = 20 for samples on day 49. Shown are geometric mean titers + SD and a and b, medians are shown in (c).