生物玻璃活性陶瓷复合人骨形态发生蛋白2基因修饰骨髓间充质干细胞

摘要 背景：目前已有将体外培养的骨髓来源间充质细胞与支架复合后修复骨缺损的临床报道，但是由于该类复合材料中缺乏骨生长因子作用，其原位的成骨作用并不十分理想。 目的：观察人骨形态发生蛋白2基因修饰的骨髓间充质干细胞与生物活性玻璃陶瓷复合材料在修复兔颅骨缺损中的原位成骨作用。 方法：复苏冻存的人骨形态发生蛋白2基因修饰的骨髓间充质干细胞，与生物活性玻璃陶瓷复合培养获得人工植骨材料；制备兔双侧颅骨全层骨缺损模型，实验组将人工植骨材料植入骨缺损区，并设置空白质粒转染的骨髓间充质干细胞+生物活性玻璃陶瓷、骨髓间充质干细胞+生物活性玻璃陶瓷、空白组作对照，术后第4，8，12周对植骨区进行大体观察、X射线摄片、组织化学检测和生物化学检测。 结果与结论：转染人骨形态发生蛋白2 的骨髓间充质干细胞与生物活性玻璃陶瓷复合培养的人工植骨材料植入后第4周，骨缺损外周骨质与复合材料之间大部分被高密度阴影充填；第12周，完全被高密度阴影充填；第8周，骨小梁大部分相连成片；第12周，骨小梁粗大，骨髓再生。生物化学检测结果与组织化学检测结果一致，并且成骨效果及成骨活性明显优于对照组。说明携带人骨形态发生蛋白2基因的骨髓间充质干细胞与生物活性玻璃陶瓷复合构成的人工植骨材料基本符合骨组织工程学的要求，在骨缺损区原位具有良好的成骨作用。 关键词：骨髓间充质干细胞；基因转染；生物活性玻璃陶瓷；骨缺损；移植；兔；生物材料 doi:10.3969/j.issn.1673-8225.2010.42.005

Bone marrow mesenchymal stem cells transfected by human bone morphogenetic protein-2 and bioactive glass ceramics composite material for repair of skull defects

Abstract BACKGROUND: The current studies have reported in vitro cultured bone marrow mesenchymal cells combined with scaffolds to repair the bone defects. However, the bone formation in situ remains un-satisfactory due to lack of bone growth factor in such composite. OBJECTIVE: To investigate the in situ osteogenic effect of artificial bony graft, formed by bone marrow mesenchymal stem cells (BMSCs) modified by human bone morphogenetic protein-2 (hBMP-2) and bioactive glass ceramics (BGC) for repairing skull defects of rabbits. METHODS: The BMSCs transfected hBMP-2 gene were cryoopreserved and resuscitated, then composited with BGC to prepare artificial bony graft. Rabbits skull defect models, created on the both parietal bones, were filled with the artificial bony graft, as the experimental group. While those treated by blank plasmid-transfected BMSCs + BGC and simple BMSCs + BGC, as the control groups. Blank control group was also set. The bone defects were observed by gross observation, X-ray, immunohistochemical and biochemical detections in the 4th, 8th, 12th weeks after operation respectively. RESULTS AND CONCLUSION: At four weeks after BMSCs transfected with hBMP-2 and BGC composite materials were transplanted into the skull defect, the interspace of artificial bone and bone defect were mainly filled by high density shadow in the experiment group, at 12 weeks, the space were completely filled by high density shadow. The great part of bony trabeculae were connected each other at 8 weeks, and bony trabeculae become thicker and formed as a network and new marrow regenerated at 12 weeks. The outcomes of biochemistry were coincided with the outcome of immunohistochemistry. The bone formation and osteogenesis activity were markedly better than those in control groups. The artificial bony graft formed by BMSCs transfected by hBMP-2 and BGC may satisfy the requirement of bone tissue engineering and has good effects for accelerating the bone defects healing.