[Expanding capacity of mesenchymal stem cells from patients after hematopoietic stem cell transplantation]

The aim of this study was to investigate the expanding capacity of bone marrow-derived mesenchymal stem cells (MSCs) in 34 patients who received a marrow and/or peripheral blood stem cells transplant (SCT). Marrow samples were obtained from iliac crest aspirates of healthy individuals (normal controls) and patients for the isolation, purification, and expansion of MSCs. The different passage MSCs of patients were analyzed by flow cytometry (FCM) to reveal the cell surface antigen expression. The expanding function of MSCs from patients after SCT, which might be affected by cytotoxic therapy in the conditioning regimen, colony-forming unit-fibroblast (CFU-F), confluent time, and passage number of the culture were measured, and then compared with those in the normal controls. At the same time, the numbers of colony-forming unit of hematopoietic progenitor were detected and compared with normal controls. In addition, CFU-F, confluent time, and passage number of MSCs were compared between group of BMSCs plus PBSCs co-transplanted patients and group of BMSCs plus PBSCs with the second donor umbilical cord blood cells (UBCs) co-transplanted patients. The results indicated that a confluent monolayer of stroma cells was generated in 31 out of the 34 cases (91.1%), a subconfluent monolayer was generated in one case (2.9%), no adherent stromal layer was generated in 2 cases (5.9%). As compared with the normal controls, the time generating a confluent layer of stroma cells from primary MSCs of patients was longer significantly, and the passage number and CFU-F of MSCs of patients in vitro was less than that of normal controls significantly. Compared with the group of BMSCs plus PBSCs co-transplanted patients, the confluent time of MSCs in group of BMSCs plus PBMSCs with UBCs co-transplanted patients was shorter, the passage number and CFU-F count in this group were higher. It is concluded that the MSCs of patients after HSCT are damaged, and the co-transplant of BMSCs and PBSCs plus UBCs can partially improve in vitro expanding capacity of MSCs from patients.