Fig. 7

ROS-induced SENP3 accumulation regulates Treg cell stability. a, b Levels of ROS (a) and SENP3 (b) in Treg cells stimulated with anti-CD3 and anti-CD28 antibodies for the indicated time periods. Grey area, unstimulated Treg cells. CFDA, CM-H2DCFDA. c SENP3 expression in Treg cells stimulated or not with anti-CD3 and anti-CD28 antibodies for 8 h in the presence or absence of 0.5 mM or 5 mM NAC. d Foxp3 expression in Treg cells stimulated with anti-CD3 and anti-CD28 antibodies for 12 h in the presence or absence of 5 mM NAC. e SUMOylation assays using Treg cells stimulated or not with anti-CD3 and anti-CD28 for 8 h in the presence or absence of 5 mM NAC. f–h Flow cytometric analysis of percentage (f) or IFN-γ and IL-17 expression (g, h) of tumor-infiltrating Treg cells from tumor-bearing Senp3^+/+Foxp3-Cre and Senp3^fl/flFoxp3-Cre mice receiving daily NAC (on day 14). i–m B6.SJL mice were injected (s.c.) with B16-F10 cells and then intravenously (i.v.) treated (on day 6) with Senp3^+/+Foxp3-Cre and Senp3^fl/flFoxp3-Cre Treg cells (2 × 10⁶ cells per mouse) stimulated with anti-CD3 and anti-CD28 antibodies for 12 h in the presence or absence of 5 mM NAC. i Growth curves of tumors in B6.SJL mice (n = 8 mice per group). j Percentage of tumor-infiltrating Foxp3^–CD45.2⁺ T cells (on day 14). k–m Flow cytometric analysis of IFN-γ and IL-17 expression in tumor-infiltrating CD45.2⁺Foxp3⁺ (k, l) or CD45.1⁺CD8⁺ (m) T cells (on day 14). Data are representative of three independent experiments and are presented as the mean ± SEM. n = 5 or 8. Two-tailed unpaired Student’s t tests were performed. n.s. not statistically significant; *P < 0.05