STAT6 and graft versus host disease: To prove the indispensability of type 2 polarization for GVHD prevention in mice treated with CD11b+CD11c+ MDSCs, we reconstituted B6.bm1 mice with TCD-BM and allogeneic SCs either derived from STAT6-deficient (STAT6−/−) or B6 WT mice and CD11b+CD11c+ MDSCs.