PS1537 CO‐TRANSPLANTATION OF MESENCHYMAL STEM CELLS CAN AMELIORATES ACUTE GVHD AND VIREMIA AFTER ALLO‐HSCT FOR APLASTIC ANEMIA: A MULTI‐CENTER RETROSPECTIVE STUDY OF 75PATIENTS

Abstract

Background:Mesenchymal stem cells (MSCs) are known to exhibit immunomodulatory, anti‐inflammatory, and pro‐angiogenic properties, and therefore have the potential to improve the outcome of allogeneic hematopoietic stem cell transplantation (allo‐HSCT) for severe aplastic anemia (AA).Aims:To explore the efficacy and safety of allo‐HSCT by co‐transplantation with MSCs in AA patientsMethods:We conducted a multi‐center retrospective study to comparing the incidence and severity of acute GvHD, transplant‐related complication and overall survival (OS) of allo‐HSCT with or without co‐injection of MSCs in AA patients. A total of 75 consecutive severe AA patients (43males/32 females) undergoing allo‐HSCT at 4 hospitals from January 2012 to February 2018 were analyzed. 45 patients transplanted with donor HSCs only,and 30 patients transplanted with HSCs and MSCs. MSCs infusion dose was 0.5–3.0 × 106/kg, at day0/+1 following HSCs infusion.Results:All patients achieved successful engraftment within one month post transplant. There was no difference in time to leukocyte and platelet engraftment in the two groups. There was a trend to a lower incidence of aGVHD in the MSC group (13.3% versus 26.7%,χ2 = 2.066 P = 0.151). Moreover, a lower incidence of CMV replication in the MSC group was observed (CMV:26.7% vs 64.4 %,P = 0.003). With a median follow‐up time of 615 days (range:29–2315ays),the 2‐yr OS was similar in both groups (76.2% vs 77.3%,P = 0.883). A combination of bone marrow and peripheral blood as the sources of stem cells co‐transplanted with MSCs (n = 9) demonstrated an improved survival benefit (2‐yr OS = 100%).Summary/Conclusion:These data support that co‐transplantation with MSCs could ameliorate the challenges of aGVHD and viremia and facilitate survival in allo‐HSCT for AA patients.