TNFα/TNFR2 disruption using TNFR2-KO Tregs abolishes the protective effect of Treg after allo-HCT. [B6 x C3H]F1 female mice underwent TBI followed by transplantation with B6 BM cells plus T cells or with B6 BM cells plus T cells supplemented with HY-Tregs produced from WT B6 or from TNFR2-deficient mice in order to prevent GVHD. HY peptide was administered at day 0, 1, 3, and 6. The experiment was performed twice, and the resulting survival and clinical score data were pooled. Kaplan-Meier survival curves (A) and curves of evolution of GVHD clinical score (B) over time were compared between the 3 groups of mice. *P < .05; **P < .01; ***P < .001.