FIG. 3.

Anti-NP immunoglobulin subtype profile. Female BALB/c mice were injected with NP DNA (50 μg) or NP protein (10 μg) on weeks 0 and 3, and sera were collected on week 5. Anti-NP antibody subtypes were measured by ELISA as described in Materials and Methods. Data are presented as geometric mean ELISA titers ± standard errors of the means for groups of five mice.