Intranasal vaccination with LAIV permits expansion of FluM1-specific CD8⁺ T cells. (A) Blood of mice vaccinated with LAIV intraperitoneally/intravenously (i.v./i.p.) as in Figure 1 or intranasally (i.n.). Frequency of CD8⁺ T cells binding FluM1 tetramer at day 12 after vaccination. (B) Flu-M1 specific CD8⁺ T cells in draining and control lymph node (LN) suspension pooled from 3 mice; blood, spleen, and lung from representative mouse.