兔骨髓基质干细胞促进珊瑚骨成骨的实验研究

Rabbits＇ bone marrow stromal stem cells enhance osteogenesis of coral scaffolds

目的探讨运用组织工程技术合成自体骨移植的替代物的可行性。方法从兔骨髓中分离基质干细胞进行体外培养扩增后，载人明胶海绵或珊瑚骨制成复合物。取24只6～9个月龄雌性新西兰白兔，随机分成四组，每组6只。第1组桡骨干中段15mm的骨缺损内植入明胶海绵，第2组植入明胶海绵＋骨髓基质干细胞（BMSCs），第3组植入珊瑚骨，第4期植入珊瑚骨＋BMSCs，对各组动物进行影像学、p,CT和组织学比较。结果仅植入明胶海绵的骨缺损全部形成典型的骨折不愈合表现；植入明胶海绵＋BMSCs后，骨缺损内的新骨形成明显增多，但仅有1只动物完全愈合；植入珊瑚骨后，骨缺损内有部分新骨形成，但术后16周无一例完全愈合；植入珊瑚骨＋BMSCs后，骨缺损内的载体支架被逐渐吸收的同时有大量的新骨形成，其中4只动物完全愈合。结论由体外分离和培养的BMSCs与珊瑚骨合成的组织工程骨具有可吸收性强、成骨能力好等特点，是一种具有发展前景的自体骨移植材料替代物。

Objective To synthesize autogenous bone gaffing substitutes by tissue engineering. Methods Bone marrow stromal cells（BMSCs） were isolated and cultured form bone marrow of 24 New Zealand white rabbits which were then made models of a 15-mm defect on the midpiece radial shaft. The defects were filled in 4 different ways, collagen sponges loaded with or without BMSCs and coral scaffolds loaded with or without BMSCs, with 6 animals for each. Radiographs were obtained every 4 weeks. After 16 weeks, animals were killed. New bone was measured by μCT scans and samples were accessed by histological methods. Results Collagen group and coral group showed no or partial defect healing, only 1 animal in the collagen ＋ BMSCs group showed total bone regeneration, whereas 4 animals in the coral ＋ BMSCs group showed extensive or total bone regeneration. Significantly more bone was found in the coral ＋ BMSCs groups. Conclusion Osteogenesis can be promoted by coral scaffold loaded with BMSC that is an appropriate bone grafting substitute for autogenous bone.