间充质干细胞在致敏受者造血干细胞移植中的作用

Effects of Mesenchymal Stem Cells in Hematopoietic Stem Cells Transplantation for Sensitized Recipients

【目的】本实验拟研究骨髓间充质干细胞(MSC)在致敏受者造血干细胞移植中的作用。【方法】体外分离BALB/c小鼠骨髓细胞,通过贴壁培养方法获得MSC,应用流式细胞仪检测细胞表面分子标记。通过异基因脾细胞输注方法建立致敏动物模型;绿色荧光染料标记骨髓MSC,分别移植到非致敏及致敏受者体内,并于移植后不同时间点检测MSC的归巢情况。致敏BALB/c小鼠经照射预处理,联合应用同基因MSC与异基因骨髓细胞移植,每日观察小鼠的生存情况。【结果】体外培养第4代MSC表现为长梭形,阴性表达造血细胞表面分子而阳性表达粘附分子。动物体内实验发现移植后第48小时,MSC在非致敏受者体内主要归巢于骨髓,而在致敏受者体内主要归巢于脾脏。造血干细胞移植实验中,致敏小鼠接受同基因骨髓MSC与异基因骨髓细胞移植,结果发现致敏小鼠在移植后第12～16天全部死亡,生存中位数时间是14 d。【结论】成功培养小鼠骨髓MSC;移植后MSC在致敏受者体内主要归巢于脾脏组织;联合应用MSC移植并不能有效促进异基因造血干/祖细胞在致敏受者体内植入。

[Objective ] The study was aimed to study the effects of mesenchymal stem cells （MSC） in hematopoietic stem cell transplantation for sensitized recipients. [ Methods ] Bone marrow cells derived from BALB/c mice were cultured in vitro. The molecular markers and the function of MSC were detected by flow cytometry. A murine model of sensitization was established by transfusion of allogeneic spleen ceils. MSC labeled with green fluorescent dye were transplanted into non-sensitized and sensitized recipients, and the homing of MSC in vivo was monitored at different time points post transplantation. Additionally, sensitized BALB/ c mice under irradiation were transplanted with syngeneic MSC and allogeneic bone marrow cells, and the rate of survival was monitored daily. [ Results] The results showed that the fourth passage of MSC presented typical spindle-shape morphology. The MSC were lack of expression of hematopoietic tell markers but with expression of adherent markers. Forty-eight hours post transplantation, the homing of MSC was found mainly in bone morrow of non-sensitized recipient and spleen of sensitized recipient, respectively. The hematopoietic stem cell transplantation showed that all the sensitized recipients died at 12 to 16 days after receiving syngeneic MSC and allogeneic bone marrow cells, with a median of 14 days. [Conclusion] Successfully cultured murine MSC in vitro. The MSC mainly homed to spleen of sensitized recipient post transplantation, fusthermore, MSC could not enhance engraftment of allogeneic hematopoietic stem/progenitor cells in sensitized recipients.