Immunization with PA-Av-C3d₃/IFA augments production of PA- and Domain 4-specific antibodies relative to alum.

<p>Groups of A/J (top), BALB/c (middle), and C3H/HeJ (bottom) mice were immunized with PA-Av/IFA (○), PA-Av-Alum (□), or PA-Av-C3d₃/IFA (▵). (A) Serum PA- and (B) Domain 4-specific IgG was measured by ELISA (Abs 405 nm). All mice were boosted at day 42 (↑) with PA in saline. Error bars indicate SEM (n = 5). (C) Endpoint ELISAs were performed on day 14 serum samples from PA-Av/IFA, PA-Av-Alum, and PA-Av-C3d₃/IFA immunized mice. Endpoint titers shown are 2-fold above background. Error bars represent SEM (n = 5, *p≤0.05, ** p≤0.01, *** p≤0.005).