骨形成蛋白2基因修复兔桡骨缺损的实验研究

目的观察携带人骨形成蛋白2（bone morphogenetic protein 2，BMP-2）基因的腺病毒载体（adenovirus carrying BMP-2 gene，Ad—BMP2），通过纤维蛋白凝胶与牛松质骨支架（bovine cancellous bone，BCB）复合，修复骨缺损的效果。方法将60只新西兰大耳白兔随机分为4组，每组15只。制成双侧桡骨中段1．5cm骨缺损模型，采用4种材料植入修复。A组：Ad-BMP-2＋BCB；B组：重组BMP-2＋BCB；C组：携带D-半乳糖酐酶基因的腺病毒对照载体（adenovirus carrying β—galgene，Ad—Lacz）＋BCB；D组：单纯BCB支架。修复术后各组于4、8和12周各处死动物5只取材，行X线片、组织学、生物力学和免疫组织化学染色检查。结果A、B两组骨缺损均得到了修复，但术后各时间点，A组在成骨活跃程度、新生骨量、力学强度及BMP-2表达等方面均明显优于B组；C、D两组均无新骨形成。结论BMP-2直接基冈治疗，操作简便、骨诱导能力强，是修复节段性骨缺损的有效方法。

DIRECT BONE MORPHOGENETIC PROTEIN 2 GENE THERAPY FOR REPAIRING SEGMENTAL RADIAL DEFECT IN RABBITS

Objective To study the effect of direct bone morphogenetic protein 2 (BMP-2) gene therapy mediated by adenovirus on repairing bone defect. Methods The radial defect models were made on 60 rabbits, which were evenly divided into 4 groups randomly. The 4 groups were treated with different materials: group A, adenovirus carrying BMP-2 gene (Ad-BMP-2) plus bovine cancellous bone (BCB); group B, reconstructed BMP-2 plus BCB; group C, Ad-Lacz plus BCB; and group D, only BCB scaffolds. The X-ray, histological examination, biomechanics analysis, and immunohistochemical staining were made 4, 8, and 12 weeks after the operation. Results Group A gained better effect in the volume of new bones, the anti-bending intensity of the healing bone, and the expression of BMP-2 than those of group B. The defect in group A was healed. No new bones were observed in group C and group D. Conclusion Direct BMP-2 gene therapy is easy to perform and has very strong osteoinduction ability. It is a good method to repair segmental bone defects.