组织工程骨与Bio-Oss修复大鼠下颌骨缺损的比较研究

Tissue Engineering Bone and Bio-Oss in the Restoration of a Mandibular Critical Size Defects in Rats

目的:利用组织工程骨(tissue engineering bone)修复大鼠下颌骨缺损,观察血管内皮生长因子(vascular endothelial growth factor,VEGF)在组织工程骨修复骨缺损中的作用,为解决临床种植术中的骨量不足提供一定的实验依据。方法:实验中植入不同类型的骨替代材料用于修复大鼠下颌骨缺损,植入物分别为:①牛无机松质骨骨粉(Bio-Oss);②Bio-Oss+骨髓基质细胞(bone marrow stromal cells,BMSC);③Bio-Oss+VEGF基因转染后的BMSC。大鼠分别于植入后第4、12周处死,取下颌骨进行大体观察、X线观察、HE染色以及免疫组织化学染色观察,并分析实验结果。结果:相对于第一组,第二、三组的骨粉吸收速度更快,血管新生和成骨作用更好。其中第三组的血管新生、骨再生以及支架材料的吸收均要优于其他两组。结论:VEGF对组织工程骨的血管化起了重要的作用,尤其是通过外源基因导入BMSC构建的组织工程骨明显加快了骨组织的再生过程。

Objective： This study aimed to observe the role of VEGF within tissue engineering bone in the restoration of rat mandibular bone defect. Methods： Three different kinds of bone substitutes were implanted in rat mandibular bone defects： group 1, Bio-Oss; group 2, Bio-Oss with BMSC; group 3, Bio-Oss with VEGF-transfected BMSC. Animals were sacrificed at 4-week and 12-week after implantation. Gross anatomy, radiology, histopathology and immunohistochemistry were evaluated. Results： Tissue engineering bone in group 2 and group 3 demonstrated was more enhanced vaseularization, osteogenesis and bone substitute resorption as compared to group 1. The highest degree of osteointegration was found in group 3, which also led to the highest vascularization and fastest resorption of the bone substitute. Conclusion： VEGF may be a positive factor for vascularization and osteogenesis of tissue engineering bone in bone regeneration, especially when it was expressed through gene technique.