MICA and acute graft versus host disease: By analyzing a cohort of 172 matched pairs of unrelated HCT, Parmar et al. showed a higher rate of grade II–IV acute GVHD in MICA-mismatched vs. -matched patients, taking only account of MICA mismatches in the GVHD direction (75 vs. 39%, P = 0.02) (16).