Increased frequencies of MDSCs in PBMCs of patients after allo-HSCT. (A) At the time of engraftment, the levels of MDSCs in PBMCs were compared between patients and normal controls (i), and were further analyzed according to aGVHD scores (ii). (B) After allo-HSCT, comparisons of MDSCs frequencies were performed between patients and normal controls grouped by aGVHD (i) and aGVHD severity (ii). (C) The dynamic changes of MDSCs frequencies after allo-HSCT were monitored in patients with aGVHD (i) and were analyzed based on aGVHD scores (ii). (D) The systematic monitoring of MDSCs frequencies was performed in all patients during the first 100 days after allo-HSCT grouped by aGVHD scores (i) and aGVHD severity (ii).