Fig. 3

Influenza-specific and bystander CD8 T cell numbers are higher in IL-4C-treated mice than in controls. Cells were isolated from lungs, peribronchial lymph nodes (LNs), and spleens on day 5 after influenza infection. A CD8 T cells from each organ were stained with H-2D^b/NP_366–374 and H-2D^b/PA_224–233 pentamers (H-2D^b/NP&PA) and analyzed via flow cytometry. Representative dot plots and the summarized proportions of virus-specific CD8 T cells are shown. The numbers in the dot plots are pentamer⁺ cell percentages. B Cells from lungs were restimulated ex vivo with NP_366–374 peptides in the presence of monensin for 5 h and then stained with anti-IFN-γ or TNF-α antibodies. Representative dot plots and the summarized proportions of cytokine-producing CD8 T cells are shown. The numbers in the dot plots are cytokine-producing cell percentages. C Flow cytometry yielded the antigen-specific (pentamer-, IFN-γ-, or TNF-α-positive) and D bystander (pentamer-negative CD44^hi or CD44^low) CD8 T cell numbers. The data are the means ± SDs (n = 5 or 10/group); the x-values are fold changes. Statistical analysis was performed using an unpaired t-test. n.s, not significant. *p < 0.05; **p < 0.01