Wnt5a修饰的bMSCs对白血病小鼠造血及白血病细胞生长的影响

探讨Wnt5a基因修饰的骨髓间充质干细胞（bMSCs）对急性髓系白血病小鼠体内造血和白血病细胞生长的影响。方法:外周血瑞氏染色、骨髓流式细胞仪鉴定移植性HL60人白血病重度联合免疫缺陷(SCID)小鼠模型。造模成功的SCID小鼠，随机分为实验组（A组:Ad5-Wnt5a-bMSCs+模型小鼠）；对照组（B组:Ad5-GFP-bMSC+模型小鼠；C组:bMSC+模型小鼠；D组:模型小鼠）。RT-PCR检测外源性Wnt5a基因经骨髓腔移植入白血病小鼠模型后的定植情况。骨髓MSC及CFU-Mix培养、流式细胞仪、组织细胞化学及组织病理检测白血病小鼠移植前后各组外周血、骨髓、肝、脾、肾中的白血病细胞以及骨髓造血的变化。结果:成功建立急性髓性白血病模型；外源性Wnt5a基因转染人bMSCs，转染率达37.38%。外源性Wnt5a基因成功定植于受体骨髓中。Wnt5a基因修饰bMSCs移植后,与对照组比较，实验组SCID小鼠生存率明显提高，差异有统计学意义（P<0.05）；外周血有核细胞及瘤细胞计数明显降低，差异有统计学意义（P<0.05）；CFU-Mix和MSC集落生长恢复较快，集落数明显增多，差异有统计学意义（P<0.05）；小鼠骨髓、肺、肝、脾、肾CD33阳性率明显降低，差异有统计学意义（P<0.05）。结论:Wnt5a基因修饰的bMSCs在体内能有效地抑制白血病细胞生长,支持骨髓造血。 

Effect of Wnt5a-Modified bMSCs on Hematopoiesis and on the Growth of Leukemia Cells in Leukemia Mice

To investigate the effect of the Wnt5a-modified bone mesenchymal stem cells (bMSCs) on hemopoiesis and leukemic cell growth of mice with acute myeloid leukemia. Methods: A human leukemia model with severe combined immunodeficiency (SCID) was intravenously inoculated with HL60 cells. Wright staining on the peripheral blood and identification using a bone marrow flow cytometry were performed. The well-modeled mice were divided into four groups: the experimental group (Group A, Ad5-Wnt5a-bMSCs + model mice) and the control groups (Group B, Ad5-GFP-bMSC+ model mice; Group C, bMSC+ model mice; and Group D, model mice).The exogenous Wnt5a-modified bMSCs were transplanted into the leukemia mouse model through the marrow cavity, and the colonization was detected using RT-PCR . Changes in the leukemia cells and marrow hemopoiesis in peripheral blood, bone marrow, liver, spleen, and kidney before and after transplantation were determined using histocytochemistry, RT-PCR, flow cytometry, histopathology, bone marrow MSC, and CFU-Mix culture. Results: A model of acute myeloid leukemia was successfully established. The exogenous Wnt5a gene was successfully transfected into bMSCs at a transfer rate of 36.8% and into the bone marrow of the receptors. After the transplantation, the SCID mice in the experimental group exhibited significantly higher survival rates ( P < 0.05 ) and significantly lower nucleated cell and tumor cell counts in the peripheral blood ( P < 0.05 ) compared to the control group. Furthermore, the CFU-Mix and MSC colony growth and recovery were faster. The number of colonies was significantly higher ( P < 0.05 ), and the positive rate of CD33 expression in the bone marrow, lung, liver, spleen, and other organs in the experimental group was considerably lower ( P < 0.05 ). Conclusion: The Wnt5a-modified bMSCs can effectively inhibit the growth of leukemia cells in vivo and support bone marrow hemopoiesis.?