The breadth and effector phenotype of elicited influenza-specific CD8⁺ T cells. Vaccination as indicated in figure panels. Single-cell suspensions from tissues harvested at day 14 after vaccination were stimulated for 8 hours with indicated peptides and antibodies against CD28 and CD49d. The frequency of IFN-γ–secreting CD8⁺ T cells by flow cytometry. (A-D) Spleen analysis. (A) Representative experiment. (B) IFN-γ–secreting CD8⁺ T cells (mean ± SEM, n = 3) after stimulation with indicated peptides. (C) Analysis after vaccination with TIV or TT. (D) The frequency of IFN-γ–secreting CD8⁺ T cells (mean, n = 4) specific to indicated peptides. (E) Blood: specific CD8⁺ T cells binding FluM1 and NS1 tetramer in humanized mice vaccinated with LAIV or TIV. (F) Blood and lungs of TIV or TT-vaccinated mice. IFN-γ and CD107a expression by CD8⁺ T cells in response to HIVgag or FluM1 peptides.