Figure 3. IL-33 promotes T_reg cell stability and function in vivo.

a, C57BL/6 Rag1^−/− mice were injected with CD45.1⁺ naïve T cells alone (RB^hi, n = 4) or in combination with WT (n = 4) or St2^−/− (n = 6) CD45.1⁻ T_reg cells. Mice were sacrificed after 6-8 weeks post transfer and colitis scores are shown. b, Absolute numbers of colon lamina propria (LP) cells from mice in (a). c, C57BL/6 Rag1^−/− mice were injected as in (a) and sacrificed at 2 weeks post injection. Representative plots are gated on colonic T_reg cell progeny (CD45.1⁻). d, Ratio of RB^hi T cell progeny (CD45.1⁺) to WT or St2^−/− Foxp3⁺ T_reg cell progeny (CD45.1⁻) in the colon (n = 5 per group) from mice in (c), (mean ± s.e.m). e, C57BL/6 Rag1^−/− mice were injected as in (a) and sacrificed at 8 weeks post injection. Representative plots are gated on colonic T_reg cell progeny (CD45.1⁻). f, Ratio of RB^hi T cell progeny (CD45.1⁺) to WT or St2^−/− T_reg cell progeny (CD45.1⁻) in the colon from mice in (e), (mean ± s.e.m). g, Absolute numbers of RB^hi T cell progeny (CD45.1⁺) in the colon from mice in (e), (mean ± s.e.m). h, Analysis of Foxp3 expression in colonic Foxp3⁺CD45.1⁻ T_reg cells presented as gMFI (mean ± s.e.m).

Results are representative of two independent experiments. *P<0.05 **P<0.01 *** P<0.001 **** P<0.0001 as calculated by 1way-ANOVA with Bonferroni post-test or Students’ t-test.