Figure 3. Mucosal SlgA responses induced by co-immunization of chitosan-pAIM2 and chitosan-pVP1. Mice were immunized 4 times with vaccines at 2-wk intervals. Two weeks after the initial immunization, mucosal SlgA antibody elicited by intranasal immunization was detected. (A) Fecal IgA levels were measured by ELISA at indicated time points. (B) Antibody titers, (C) Neutralizing titers, and (D) Affinity index were determined at week 10. Data are from one representative experiment of 3 performed and presented as the mean ± SD (n = 10). **P < 0.01, ***P < 0.001, ND, not detected.