FIG 2.

Single-dose intranasal adenoviral universal influenza vaccine induces antibody and T cell immunity. (A) Adult (8- to 10-week-old) female mice were vaccinated once with A/NP-rAd, B/NP-rAd, or PBS by the intranasal route. Twenty-eight days after vaccination, serum was collected to analyze antibody responses, while a subset of mice (n = 3/group) was euthanized at 34 days after vaccination to analyze T cell immunity in the lungs and IgA antibody responses in BAL fluid. (B to E) IgG antibody responses against A/NP (B) and B/NP (C) and IgA antibody responses against A/NP (D) and B/NP (E) were determined by ELISA. (F) T cell responses were measured by ELISPOT detecting IFN-γ-secreting cells in response to stimulation by indicated peptides. Data represent the average number of IFN-γ-positive lung cells per 10⁶ cells from 3 mice per immunization group, with each sample run in triplicate. Bars show mean ± SEM for three animals. Converting to total responding lung cells per animal, results correspond to, for example, a CD8 response to the NP366 epitope in the lungs of A/NP-immunized mice of approximately 25,000 cells/mouse.