Fig. 7.
CD4+ CD25+ Foxp3+ cells (Treg) modulate the Th17 cytokine profile. a Intracellular FACS analysis of naïve and tumor bearing CD4+ lymphocytes. Treg are significantly higher in glioma-bearing mice versus naïve splenocytes (P = 0.01), and they increase significantly in the presence of TGF-β (P = 0.001 in gl-splenocytes; P = 0.02 in n-splenocytes). nTh17 produced higher levels of IFN-γ than IL-10 (P = 0.001) that appeared reduced by TGF-β (P = 0.01). On the contrary, gTh17 produced more IL-10 than IFN-γ (P = 0.002). The presence of TGF-β promoted a relevant decrease in IFN-γ (P = 0.01) and a significant increase in IL-10-producing T cells (P = 0.03). Notably, the absolute number of Th17 cells obtained from the same number of splenocytes did not change significantly (nTh17 8.1 × 105; TGF-nTh17 8 × 105; gTh17 7.9 × 105; TGF-gTh17 9.2 × 105). Data are relative of three independent experiments. b Intracellular FACS analysis of tumor bearing CD4+ lymphocytes. PC61 antibody (0.5 μg/1 × 106 cells) decreased Treg population from gl- and TGF-gl-splenocytes (P < 0.001), increasing IL-17/IFN-γ production (gTh17 P = 0.05; TGF-gTh17 P = 0.01) and decreasing IL-17/IL-10 secretion (gTh17 P = 0.0004; TGF-gTh17, P = 0.003). Data are statistically significant when they are compared to the same culture condition without PC61 (Fig. 7a). No significant differences (P > 0.05) were found in the same experiments performed with IL-6. In vitro data are represented as mean ± SD obtained combining percentage obtained from 24 to 48 h pre-stimulation of splenocytes