Figure 6. Reduced efficacy of ILC2s in the absence of IL-13.

B6D2 recipients of B6 TCD BM (BM only), BM plus splenic T cells (BM + T cells), or BM plus T cells with cultured Il13^–/– ILC2s (BM, T cell + Il13^–/– ILC2) were evaluated by (A) Kaplan-Meier plot for survival following allo-SCT. Results of 1 representative of 2 combined experiments are shown (n = 8 per group in each experiment). WT ILC2 group shown represents one experiments from Figure 2A. Immune infiltrates were evaluated in GVHD target organs by flow cytometry 12 days after allo-SCT with or without Il13^–/– ILC2s. (B) Total number of IFN-γ–producing donor CD4⁺ and CD8⁺ T cells and the number of donor CD4⁺ T cells producing IL-17A in the colon LP. Data represent 2 independent experiments; mean ± SEM (n = 5 each). (C) Frequencies of CD11b⁺GR-1⁺Ly-6C⁺Ly-6G⁺ MDSCs (gated on donor CD45⁺cells) in the colon and small bowel of BMT recipients of Il13^–/– ILC2s 12 days after transplant. Results represent 2 independent experiments; mean ± SEM. (D) BM-MDSCs were cocultured for 72 hours with WT or Il13^–/– ILC2s (1:1), or MDSCs alone or with either IL-13 (80 ng/ml) or IL-7 and IL-33 (10 ng/ml each). BM-MDSC were cocultured with WT or Il13^–/– ILC2s (1:1) in Transwell assays, alone or in the presence of IL-13 only. Results represent 2 independent experiments; mean ± SEM. One-way ANOVA with Bonferroni’s correction for multiple comparisons, *P < 0.05, ***P < 0.001.