Fig. 2

GITR is intrinsically required for the accumulation of IFNγ-producing CD4 and CD8 T cells during influenza infection. Mixed bone marrow chimeras were generated and infected as described in Fig. 1. Freshly isolated cells from the lung and splenocytes from chimeric mice were restimulated with live influenza virus for 18 h a, b or with D^b-restricted influenza peptides: NP_366–374 or PA_224–233 for 6 h c, d, after which intracellular cytokines were measured by flow cytometry. a Representative flow cytometry plots depicting CD4⁺IFNγ⁺ T cells in the GITR^+/+ and GITR^−/− compartments day 7 p.i. in the lung. The normalized GITR^+/+: GITR^−/− ratio in CD4⁺IFNγ⁺ T cell b, CD8⁺IFNγ⁺ T cell (NP restim) c, and CD8⁺IFNγ⁺ T cell (PA restim) d compartments was evaluated at day 7 or day 10 p.i. in the lung and spleen. Normalization was done as described in Fig. 1. Each symbol represents an individual mouse, with bars indicating median with IQR. Statistical analyses performed using Wilcoxon test comparing pre- and post-infection ratios. Data were pooled from 10 to 16 individual chimeric mice from at least two independent experiments