FIGURE 5.

PA-specific Abs after intranasal immunization with PA mutants and EFwt. A, Serum PA-specific Ab isotype and IgG subclass responses after intranasal administration of EdTx derivatives. Mice were immunized three times at weekly intervals with 2 µg PA only (horizontal-striped bar); 2 µg PA plus 2 µg EF (filled bar); 2 µg PA-U7 plus 2 µg EF (diagnol-striped bar); or 2 µg PA-dFF plus 2 µg EF (stippled bar). The PA-specific IgA, IgG, and IgG subclass responses were determined 1 wk after the last immunization. B, PA-specific Ab responses in saliva and vaginal secretions were determined 2 wk after the last immunization. The results are expressed as the reciprocal log₂ titers ± 1 SD and are from three experiments and five mice/group. Statistical significance: *p ≤ 0.05 when compared with mice immunized with PA only.