Fig 5. TLR2 and RA act in concert to potentiate iT_REG generation via IL-10 production.

Foxp3 and IL-10 expression by WT and TLR2KO T cells stimulated with Pam2CysK4 (A) or cecal lysate (B) in the presence or absence RA, TGF-β or RA/TGF-β. Data are representative plots from three independent experiments for (A) and mean and frequency of Foxp3⁺IL-10⁺ and IL-10⁺CD4⁺ T cells from WT (white bars) and TLR2KO (gray bars) treated with cecal lysate (n = 5–7 mice) for (B). (C) Frequency of Foxp3 and IL-10 expression in WT T cells cultured with Pam2Cysk4, RA and TGF-β and treated with anti-IL-10Rα antibody or isotype control. Data are representative FACS plots from six independent experiments shown in the bar graphs. (D) Cytokine production from re-stimulated in vitro MLN cells of WT and TLR2KO mice fed OVA. Data are the mean ± SEM of two independent experiments with three mice per group. *, p < 0.05, **, p < 0.01.