AACB/BMP/bFGF复合物修复犬股骨头中再血管化与新骨形成的作用

目的观察吸附有骨形态发生蛋白（BMP）及碱性成纤维细胞生长因子（bFGF）的异体脱抗原松质骨（AACB）植入股骨头坏死（FHN）病灶清除区骨缺损后的修复过程,评价bFGF对FHN的再血管化作用与新骨形成的关系. 方法建立液氮冷冻诱导性犬FHN模型,以AACB/BMP/bFGF作为材料充填骨缺损处.术后行组织学大体和光镜观察,组织切片免疫组化血管染色,进行血管计数和新生骨面积图像分析,并分析再血管化作用与新骨形成之间的关系.结果①免疫组化血管计数：术后第3周移植孔隙内大量血管增生;第6、12周时血管数量进一步增加.②组织切片光镜观察：术后第3周移植物周围间充质细胞大量增生,新骨开始形成;第12周充填区广布成熟骨小梁.术后第3周新骨面积占视野的7.73%;第6、12周时新骨面积进一步加大.③血管形成与新骨形成的关系：术后所有时间点血管数与新骨形成面积呈正相关关系. 结论 AACB是生长因子的良好吸附载体,适宜新生血管长入.吸附有bFGF及BMP的AACB具有较强的再血管化能力,bFGF促进再血管化的同时,加速新骨形成.这一疗法有望成为FHN治疗的一种手段.

The effects of AACB absorbing BMP/bFGF on revascularization and new bone formation in femoral head defects and necrosis of canines

Objective To observe the repairing process after BMP/bFGF-absorbing AACB(allogeneic antigen-extracted cancellous bone) being infilled into the necrotic areas of the femoral head, and to evaluate the revascularization effect of bFGF on the femoral head necrosis(FHN)and the correlation between revascularization effect and new bone formation. Methods BMP/bFGF-absorbing AACB was infilled into the defective and necrotic areas of the femoral heads in canines after the defect had been frozon by liquid nitrogen. Gross, histopathological changes, immunohistochemical vessel staining, vessel count and new bone surface area image analysis, and the correlation between revascularization effect and new bone formation were investigated in the femoral heads after the operation. Results With vessel count in immunohistochemical vessel staining, a large quantity of new vessel proliferated around the infilling material on the 3rd week was found. Its quantity continuously increased on the 6th and 12th week. Under the microscope, a large quantity of mesenchymal stem cells proliferated around the infilling material, and new bone trabeculae formed and began to elongate into the infilling areas on the 3rd week. On the 12th week, the infilling areas were full of matured trabeculae. The ratio of new bone cross section and the microfield of vision was 7.73% on the 3rd week. This ratio continuously increased on the 6th and 12th week. The correlation between revascularization effect and new bone formation was positive at every definite time point. Conclusions AACB, a kind of fine carrier of growth factors, is suitable for new vessel in growth. AACB/BMP/bFGF compsite has a strong activity of revascularization effect and bFGF can facilitate revascularization and improve the new bone formation. This therapy may be a treatment of choice for femoral head necrosis in the future.