FIG. 2.

Characterization of humoral immune responses induced by rAd/3xG. (A) BALB/c mice were immunized once with rAd (rAd/1xG, rAd/3xG, or rAd/control) or with live RSV A2 via the indicated routes, and systemic anti-RSV IgG antibody titers were measured by serum ELISA 3 weeks after immunization. The results represent log₂ end point values from four or five individual mice. (B) Average IgA titers in the BAL fluid were measured 3 weeks after rAd/3xG immunization. Error bars indicate the standard deviation. (C) Total IgA titers in the supernatants of lung homogenates were determined for each group 4 days after RSV challenge. (D) Fourteen-day-old pups were immunized with 3 × 10⁷ PFU of rAd/3xG or rAd/control in a volume of 20 μl. Anti-RSV IgG antibody titers were determined 2 weeks later.