[Transfusion of mesenchymal stem cells combined with haploidentical HSCT improves hematopoietic microenvironment]

The aim of this study was to investigate the role of mesenchymal stem cells in the hematopoietic reconstitution of patients who had received haploidentical allogeneic hematopoietic stem cell transplantation (hi-allo-HSCT). 15 patients who underwent treatment with both MSCs and HSCs, were selected as study group, while 20 patients receiving only HSCT were taken as control. Bone marrow samples were obtained from iliac crest aspirates at several times after HSCT for the isolation, purification and expansion of MSCs. The confluent ratio and time were measured and compared with those of the control. The peripheral blood samples were obtained from patients, then absolute neutrophil and platelet counts were assayed. From day 4 before transplantation to day 28 after transplantation, serum was obtained every four days from patients of the two groups, and then 3 cytokines as SDF-1alpha, TPO and IL-11 were detected by ELISA. The results indicated that as compared with the control group, the ratio of primary confluent layer formation of MSCs in study group was obviously higher (27.3%) (p < 0.01), and the confluence time in culture was significantly less (p < 0.05). In the study group, the concentration of SDF-1alpha amounted to peak value (2975.19 +/- 681.56 pg/ml) on the 8th day after HSCT, which was obviously higher than that before HSCT (2403.70 +/- 522.39 pg/ml, p < 0.05), whereas in the control, the concentration of highest point of SDF-1alpha reached to peak valve (2280.60 +/- 701.25 pg/ml) on the 16th day after HSCT, which was less than that before HSCT (2701.46 +/- 483.21 pg/ml, p < 0.05). The concentration of TPO and IL-11 was higher in study group compared with the control from day 16 to 28 after HSCT (p < 0.05). It is concluded that the transfusion of MSCs combined with hi-all-HSCT may improve the injured state of the hematopoietic microenvironment in bone marrow of patients during allo-HSCT.