Fig. 6. Systemic and mucosal antibody responses.

pH1N1 (a), H3N2 (b) and NA2 (c) specific IgG responses in serum were determined by ELISA at the indicated time points. pH1N1 (d) and H3N2 (e) IgG and H1N1 (f) and H3N2 (g) IgA responses in BAL, were determined by ELISA 4 days after the H3N2 challenge. The mean and standard error (SEM) is presented in each time point (a–c). Significant statistical differences are listed in Table 1. The top of each bar indicates the mean and the line the SEM. Each symbol (circle, square and triangles) represents one animal (d–g). Asterisks denote significance between indicated groups (*p < 0.05, **p < 0.01) and were analyzed either by one-way (g) or two-way (a–c) ANOVA and Bonferroni’s multiple comparisons test when the data were normally distributed or with Kruskal-Wallis and Dunn’s multiple comparisons test when normality was not achieved (d–f).