TGF-β与BMP复合材料的骨修复作用

Effect of Composite of Transforming Growth Factor β and Bone Morphogenetic Protein on Repairing Bone Defects

目的探讨转化生长因子β（ＴＧＦ－β）与骨形成蛋白（ＢＭＰ）复合后对节段性骨缺损的修复作用，以及在骨修复过程中ＴＧＦ－β和ＢＭＰ之间的相互作用。方法采用以系列化学方法处理的小牛松质骨作为载体，将一定量的ＴＧＦ－β和／或ＢＭＰ与之复合，形成ＴＧＦ－β／载体、ＢＭＰ／载体和ＴＧＦ－β／ＢＭＰ／载体复合物（其中含ＴＧＦ－β１２０μｇ、ＢＭＰ１２ｍｇ），分别修复１．５ｃｍ兔桡骨节段性骨缺损。术后４、８、１２、１６周取材，进行放射学和组织学观察。结果术后４周，植入ＴＧＦ－β／载体的缺损区内可见不均匀絮状放射阴影，外骨膜呈增生反应，骨折线模糊不清，缺损区尚未完全桥接；植入ＢＭＰ／载体组新生骨痂明显，密度均匀，缺损区两断端骨折线隐约可见；在植入ＴＧＦ－β／ＢＭＰ／载体的缺损区可见均匀的高密度阴影，桥接骨缺损的两端，骨折线模糊。术后第１２～１６周３组缺损区完全性修复，其密度近正常骨，可见皮质骨和骨髓腔结构。１６周时ＴＧＦ－β和ＴＧＦ－β／ＢＭＰ组骨缺损区周围外骨痂少，而ＢＭＰ组中仍可见较多尚未完全吸收的外骨痂。结论ＴＧＦ－β／ＢＭＰ复合后早期骨修复作用优于单一的ＴＧＦ－β和ＢＭＰ，在骨缺损修复过程中ＴＧＦ－β和ＢＭＰ有良好的?

Aim To evaluate the effect of transforming growth factor β (TGF β) and bone morphogenetic protein (BMP) composite on the repairing of large segmental bone defects and to discuss the interaction between TGF β and BMP during bone repair. Methods Segmental bone defects for 1.5cm were created in the mid upper part of the radial shafts of 48 adult rabbits. The defects were filled with implants of TGF β/carrier, BMP/carrier, and TGF β/BMP/carrier (TGF β 120Ug, BMP 12mg) separately. The defects were examined radiographically and histologically at 4, 8, 12 and 16 weeks post operation. Results In the group with TGF β/BMP composite, the defects area was bridged with callus of uniform radiodensity at 4 weeks, and cortices of the cut ends were obscured by new bones. At 16 weeks post operation, the defects were bridged by uniform new bones and the cut ends of cortex could not be seen in all groups. In the group with BMP/carrier, the defects were filled with more irregular woven bone callus than those in the other two groups. Defects implanted with TGF β/BMP in animals killed at 16 weeks showed histologically new lamellar and woven bone which was formed in continuity with the cut ends of the cortex. Medullar canal was recanalized and contained marrow elements with normal appearance. Conclusion These data demonstrate not only the synergistic action between TGF β/BMP in the process of bone healing, but also a better effect of TGF β/BMP composite than single TGF β or BMP on bone repair, especially in the early stage of bone repair process.