Fig. 5: Tregs promote Th17 cell differentiation by reducing IL-2.

Naïve CD4⁺ T cells isolated from C57BL/6 mice were stimulated with anti-CD3 and antigen-presenting cells (APCs) in the presence or absence of Tregs (1:1 ratio), and cultured in indicated polarization conditions. A, B Representative flow cytometry plots and a bar graph showing frequencies of CD4⁺IL-17⁺ Th17 cells among T cells cultured for three days. C, D Representative flow cytometry plots and a bar graph showing frequencies of IL2⁺CD4⁺ T cells among T cells cultured for 24 h. E Amount of IL-2 in the culture supernatant was detected using enzyme-linked immunosorbent assay (ELISA) after 24 h of culture. F, G Representative flow cytometry plots and a bar graph showing frequencies of CD4⁺IL-17⁺ Th17 cells among T cells cultured in the indicated polarization conditions for three days. Data are pooled from three biological replicates. Summary data are presented as mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001, ns, not significant, unpaired two-tailed Student’s t tests. Source data are provided as a Source Data file.