核心结合因子a1基因转染的骨髓基质干细胞复合生物衍生骨支架诱导异位成骨的研究

Heterotopic osteogenesis of human mesenchymal stem cells transfected with core-binding factor a1 gene

目的观察核心结合因子a1(Cbfal)基因转染的人骨髓基质干细胞(hBMSCs)复合生物衍生骨支架异位成骨的效果。方法雌性BALB/C裸鼠18只,随机分为3组:转染Cbfa1基因的hBMSCs复合支架(A)、未转染细胞复合支架(B)和单纯支架组(C),每组6只。分别将各组人工骨植入裸鼠背部皮下,于术后4、8周行组织学、免疫组织化学和荧光原位杂交等检测。结果Cbfal基因转染后,可诱导BMSCs骨钙素、Ⅰ型胶原呈阳性表达。体内植入后,A组成骨速度及成骨质量均明显优于其他组;植入细胞及宿主间质细胞呈骨钙素、骨形态发生蛋白2阳性表达;4周时,Y染色体阳性细胞数明显高于B组。结论Cbfa1基因转染BMSCs,能够诱导其向成骨细胞分化、上调骨形态发生蛋白2基因表达并提高移植细胞的生存率,明显促进异位成骨能力。

Objective To evaluate the osteogenetic potential of human mesenchymal stem cells （hMSCs） transfected with core-binding factor al （Cbfal） gene. Methods hBMSCs transfected with Cbfal gene were seeded on allogenetic bone scaffold to construct tissue engineering bone. The composite （ group A） then were implanted subcutaneously into the back of the nude mice. Two control groups were set up in the experiment： composite of untransfected MSCs and scaffold （ group B） and only scaffolds （group C）. Histological examination, immunohistochemical staining and fluorescent in situ hybridization were conducted after 4 and 8 weeks. Results Cbfal gene transfection could induce MSCs＇ positive expression of osteocalcin and type Ⅰ collagen. After implantation in vivo,the speed and quality of bone formation in group A were much better than those in other groups. Both transplanted ceils and mesenchymal cells displayed the positive expression of osteocalcin and BMP-2;At 4th week, the number of Y chromosome positive cells was obviously more than that in group B. Conclusion Cbfal gene transfection can induce differentiation of BMSCs into osteoblast, up-regulate its BMP-2 gene expression and enhance survival rate of implanted cells,can obviously promote osteogenenic potential of BMSCs in eetopia.