Clinical Study Of Umbilical Cord Mesenchymal Stem Cells In The Treatment Of Hormone-refractory Acute Graft-versus-host Disease

Objective:To investigate the efficacy,safety and survival of umbilical cord mesenchymal stem cells in the treatment of hormone-refractory acute graft-versus-host disease in children with allogeneic hematopoietic stem cell transplantation.Methods:Retrospective analysis of the medical records of 59 children with SR-aGVHD after allo-HSCT in our hospital from February 2014 to December 2018.33 cases were treated with UCMSCs during second-line immunosuppressive therapy and divided into UCMSCs(33 patients)and conventional group(26 patients).SPSS statistical software was used to statistically analyze the effects of SR-aGVHD treatment,the incidence of chronic graft-versus-host disease(cGVHD),the virus infection rate,the recurrence rate,and the overall survival(OS)rate in both groups.Results:In the UCMSCs group,the average number of UCMSCs intravenously infused was 1.70(0.43 to 5.78)×106/kg,and the average number was 2(1 to 5)times.No adverse reactions were observed.Compared with the conventional group,the UCMSCs group had a shorter median time to improve SR-aGVHD(12d vs 18d,P=0.011);There was no statistically significant difference between the two groups in the healing time of SR-aGVHD,the overall response rate of the skin,liver,and gastrointestinal efficacy,and the complete response rate of the SR-aGVHD efficacy in single and multiple organ involvement(P>0.05).The incidence of widespread cGVHD and cytomegalovirus(CMV)infection in the UCMSCs group was lower than that in the conventional group(P>0.05),and the EBV infection rate and recurrence rate were higher than the conventional group(P>0.05).Combined with the survival curve,there was no statistically significant difference in the overall involvement survival rate,cumulative survival rate of ? degree SR-aGVHD children,multiple organ SR-aGVHD and single organ SR-aGVHD children(P>0.05).Conclusions:UCMSCs treatment of children with SR-aGVHD after transplantation has a certain effect and safety,and the improvement time is faster.Whether to prevent the occurrence of widespread cGVHD,CMV infection,increase the rate of EBV infection and recurrence after transplantation,and whether it can improve long-term survival after transplantation requires further expansion of the sample study.