大鼠股骨缺损模型中BBP增强BMP-2的骨诱导作用*

目的验证在大鼠节段性骨缺损模型中骨形态发生蛋白结合肽（BMP Binding Peptide,BBP）对于重组人骨形态发生蛋白-2（recombinent human bone morphogenetic protein-2,rhBMP-2）骨诱导作用的影响。方法 70只缺损大鼠分别分成7组,每组不同剂量的rhBMP-2＋/-1000 gBBP,4w和8w后分别摄片,动物8w后处死,股骨样本分别手工评估,采用uCT测量骨容积,随后分别采用组织学和生物力学分析。结果高剂量（10 g）rhBMP-2组术后8w可见骨愈合,骨缺损处骨完全覆盖和桥接,但低剂量（5 g和2 g）rhBMP-2组术后8w骨愈合欠佳。与单独应用rhBMP-2相比,使用低剂量的rhBMP-2复合一定量的BBP可以取得更满意的骨形成量。BBP增强rhBMP-2的骨形成活性发生于4~8w时,而在术后早期并无明显作用。单纯应用BBP仅可见骨缺损处局部的钙化,未见骨愈合。结论 BBP能显著增强rhBMP-2的骨形成活性,这种增强作用需要一定时间来产生效果;其活性发生于术后4~8w时,在术后早期并无明显作用。而且BBP本身并没有骨诱导潜力,仅仅能增强rhBMP-2的骨形成活性。BBP起到缓释作用,与rhBMP-2紧密结合后,让rhBMP-2缓慢而持久的释放。

Enhancement of BMP Binding Peptide Combined with Recombinant Human BMP-2 on the Heal of a Rodent Segmental Femoral Defect

Objective To elucidate the potential enhanced efficacy of BBP using critical-sized segmental femoral bone defects in rats.Method 70 defects in 7 groups of rats were filled with various amounts（0,2,5,and 10 g） of rhBMP-2 with or without 1000 g BBP.Radiographs were obtained after 4 and 8 weeks.The animals were euthanized at 8 weeks,and femoral specimens were assessed manually,evaluated for bone volume using microcomputed tomography,and subjected to histological or biomechanical analysis.Result Although 10 g rhBMP-2 yielded consistent results in terms of bone healing and quality of bone repair across the segmental defect,lower doses of rhBMP-2 failed to induce satisfactory bone healing.However,the combined administration of lower doses of rhBMP-2 and BBP induced the formation of significantly large amounts of bone.Conclusion Our results suggest that the combined administration of rhBMP-2 and BBP facilitate bone healing and have potential clinical applications.