OBJECTIVETo investigate the effect of the third-party bone marrow-derived mesenchymal stem cells (BMSCs) on the allogeneic skin transplantation.

METHODS40 female C57BL/6 mice and 50 male BALB/C mice were respectively used as donors and recipients of skin transplantation. 50 BALB/C mice were divided randomly into 5 groups: Blank control group, Cyclophosphamide group BMSCs group, Cyclophosphamide + BMSCs group and CM-DiI staining group, with 10 mice in each group. Before skin transplantation, high-dose abdominal injection of Cyclophosphamide (200 mg/kg, 2 d) was performed in recipient mice. On the transplantation day, a bonus of 1 x 10(5) BMSCs of the SD rat (SD-BMSCs) were injected through the tail vein. The observation of skin grafts, mixed lymphocyte culture (MLC), HE staining, the observation of CM-DiI-labeled SD-BMSCs and FACS were used.

RESULTSThe skin graft survival time was significantly prolonged in the Cyclophosphamide + BMSCs group, as compared with the blank control group, the Cyclophosphamide group, the BMSCs group respectively. When BMSC and lymphocyte mixed at the ratio of 1:1 and 1:10, rat BMSCs inhibited T lymphocyte proliferation. More angiogenesis and less lymphocyte infiltration were found in the experimental group than them in other groups. Red fluorescent cells were found in CM-DiI staining group under long-term observation. The SD-BMSCs can he detected by flow cytometry in the cell group and the Cyclophosphamide + BMSCs group.

CONCLUSIONSBMSCs can survive in the heterogeneous recipient body; the third-party BMSCs transplantation can prolong skin graft survival time; BMSCs can inhibit T lymphocyte activation and proliferation.