Fig 5. Survivor cells do not use PD-L1 to evade CD8⁺ T cell killing.

Cre-inducible reporter mice were infected with IAV_Cre. (A) Representative flow plots of CD45^- reporter⁺ (red line) and reporter^- (grey shaded) cells assessed for PD-L1 surface expression on indicated dpi. (B) Representative flow plots of PD-1 surface expression on naïve CD44^lo CD8⁺ T cells (dark grey shaded), PA₂₂₄/NP₃₆₆^- CD44^hi CD8⁺ T cells (light grey shaded), and PA₂₂₄/NP₃₆₆⁺ CD44^hi CD8⁺ T cells in the lungs of IAV_Cre infected mice on 10 dpi. (C) On 2, 5 and 8 dpi mice were treated with PD-L1 blocking antibody or control IgG. Number of CD45^- reporter⁺ cells at 10 dpi. The results (C) are compiled from two independent experiments with 3 mice per group in each experiment (± SEM).