Fig. 2.

Vaccine-induced T-cell responses cross-react with heterologous influenza viruses and peptides. (A) Kinetics of IFN-γ⁺ CD4⁺, and CD8⁺ T-cell responses elicited by the vaccine (with and without IL-15) as assessed by ex vivo H5N2 stimulation. Wyeth/IL-15/5Flu vaccinated group is denoted by “A” and Wyeth/mut-IL-15/5Flu vaccinated group is denoted by “B.” (B) Representative FACS plots for IFN-γ production following ex vivo stimulation with H5N2 or H7N7 virus at day 9 after Wyeth/IL-15/5Flu vaccination (splenocytes of BALB/c mice gated on FSC/SSC, CD4⁺ or CD8⁺). (C) T-cell responses were determined at day 9 after two doses of Wyeth/IL-15/5Flu. Splenocytes were stimulated with heterologous peptides having >1 aa difference with the cognate vaccine-peptide (Tables 2 and 3). Data shown in B and C represent mean ± SD from five mice; experiments were repeated at least twice.