Fig. 7
Evaluation of serum responses (HI, NI, and VN) induced by intranasal administration of the inactivated 22W_KY virus in mice. (a) Schematic representation of the experimental design. Groups of five six-week-old BALB/c mice were intranasally immunized with 22W_KY inactivated with F/A, BEI, or BPL, followed by booster immunization. Three weeks after the booster immunization, nasal wash (NW), bronchoalveolar lavage (BAL), and serum samples were collected for immunological assays. (b-d) Hemagglutination inhibition (HI), neuraminidase inhibition (NI), and virus neutralization (VN) assays were performed using collected serum samples to assess the immune responses against the vaccine strain 22W_KY, as well as the SNU50-5 and PR8 antigens. All the data are presented as the geometric mean titer (GMT) ± 95% confidence interval (CI). Statistical significance was analyzed using one-way ANOVA with Tukey’s multiple comparisons test after all titer values were converted to log2 values. Significant differences are denoted by asterisks, with asterisks displayed directly above the bars indicating statistical significance compared with the negative control (**p < 0.01, ***p < 0.001, ****p < 0.0001, ns: not significant)