Relatively, in a MHC‐mismatched murine transplant model, recipients of Flt3L‐treated BM (containing a higher proportion of inactivated pDCs) had increased survival and decreased GVHD scores with fewer Th1 and Th17 polarised T cells post‐transplant as compared with recipients of unmanipulated BM.138. Here, FLT3LG is linked to graft versus host disease.