IL4 and neoplasm: Following culture, both splenic and tumor M-MDSCs treated with αIL-4/13Ab-ILC2-SNT had decreased Arg1 expression compared to conAb-ILC2-SNT-treated M-MDSCs (Fig. 4D), indicating that intestinal ILC2-derived IL-4 and IL-13 can promote Arg1 expression in M-MDSCs.