a, Temperature changes in GF Il4raF709 mice that were either left uncolonized or reconstituted with FMT from WT or Il4raF709 mice, then sensitized with OVA/SEB and challenged with OVA (n = 15 WT and 14 Il4raF709 mice). b,c, Total and OVA-specific serum IgE (n = 15 WT and 14 Il4raF709 mice). d, MMCP-1 concentrations post-OVA challenge (n = 6 per group). e,f, Analysis of ROR-γt and GATA3 expression in MLN Helios–NRP1– and Helios+NRP1+ Treg cells (n = 6 per group). Each dot represents one mouse. Data represent mean ± s.e.m. from two or three independent experiments. P values were derived by repeat measures two-way ANOVA (a) or by Student’s unpaired two-tailed t-test with Welch correction (b–f).