Figure 2

Nasal immunization with Hcβtre-Ad2F plus CT stimulates an enhanced nasal wash secretory (S)-IgA and elevated serum IgG1 and IgG2a anti-Hcβtre Ab titers. (A) BALB/c mice were nasally immunized with Hcβtre-Ad2F or Hcβtre plus CT, as described in Figure. 1. Three weeks after final immunization, S-IgA Ab levels in nasal washes were determined by ELISA. Mice vaccinated nasally with Hcβtre-Ad2F + CT showed significantly greater levels of Hcβtre-specific S-IgA when compared with mice nasally dosed with Hcβtre + CT. Data represent the mean ± SEM (n = 15 mice). *, p ≤ 0.001 represent the statistical differences in Hcβtre-specific S-IgA Abs between mice immunized with Hcβtre-Ad2F + CT vs. mice immunized with Hcβtre + CT. Serum IgG subclass anti-Hcβtre Ab responses on day 35 from (B) i.n. and (C) i.m. immunized mice (n = 7 mice/group) with Hcβtre-Ad2F or Hcβtre plus CT were evaluated. Significant elevations in (B,C) IgG1 and (C) IgG2a Ab titers were observed by the Hcβtre-Ad2F plus CT-immunized mice versus the Hcβtre plus CT-immunized mice: *, p ≤ 0.001.