TGFB1 and infectious otitis media: The changes in (a) CD8, PD-1, PD-L1, TGF-β1 and FOXP3 levels in the tumor nodules (Figures 5D, F) and (b) serum levels of IL-2, IL-10 and TGF-β1 (Figure 5G) in the MTE-treated mice were similar to those in the AOM/DSS mice, as seen by immunohistochemistry.