CD8A and infection: Further confirming that this loss of T-bet expression is not simply a result of the kinetics of the CD8+ T cell response, we found that influenza virus specific donor OT-I CD8+ T cells in the lungs at day 15 post-infection maintained higher levels of T-bet expression compared to donor OT-I cells within the spleens of the same mice (Supplementary Figures 2G,H).