生物衍生骨体外复合构建组织工程化骨修复兔桡骨-骨膜缺损：血管化进程及其生物力学性能

背景：目前组织工程骨的支架材料，力学性能和体内血管化问题仍没有很好解决，因而制约了临床的广泛开展。目的：观察生物衍生骨体外复合骨髓间充质干细胞构建组织化工程骨修复兔桡骨-骨膜缺损的血管化进程和生物力学性能。方法：取新西兰大白兔的骨头制备生物衍生骨；体外分离和培养兔骨髓间充质干细胞，定向诱导骨髓间充质干细胞向成骨细胞分化，再将诱导的成骨细胞接种到生物衍生骨支架上制成组织工程骨。取大白兔25只，制成骨膜-桡骨缺损模型，其中5只兔不做处理为空白组；另外20只兔左前肢为对照组单纯植入生物衍生骨，右前肢为实验组植入组织工程骨术后2，4，8，12周分别取5只兔标本，观察血管面积和缺损区植入骨的生物力学性能。结果与结论：术后4周实验组和对照组血液循环丰富，血管面积较大，12周血管面积趋于稳定，接近正常状态；2，4，8周的实验组和对照组血管面积与空白组比较差异有显著性意义(P < 0.05)。8周，与对照组比较，实验组修复区的血管网排列规律，12周形态结构已接近正常骨组织，力学性能明显增强。结果证实生物衍生骨复合骨髓间充质干细胞后有较好的血管化进程和力学性能，是修复骨缺损的一种较好的治疗方法。关键词：生物衍生骨；骨髓间充质干细胞；诱导；组织工程化骨；血管化；生物力学doi:10.3969/j.issn.1673-8225.2010.12.003

Repair of radius-periosteum defects using in vitro constructed tissue engineered bone in rabbits: Vascularization and biomechanical property

BACKGROUND: The biomechanical property and in vivo vascularization restrict the widely application of tissue engineering bone in clinic.OBJECTIVE: To study the vascularization and biomechanical property of tissue engineered bone in vitro constructed by bio-derived bone combined with bone marrow mesenchymal stem cells (BMSCs) in repair of radius-periosteum defects in rabbits. METHODS: The bio-derived bone was prepared using bones of New Zealand white rabbits, and the BMSCs of rabbits were harvested and cultured in osteogenic conditions, followed by incubation into bio-derived bone to prepare tissue engineered bone. Twenty-five rabbits were prepared for radius-periosteum defects models. The left forelimbs of rabbits in the control group were repaired by bio-derived bone, and the right forelimbs of rabbits in the experimental group were repaired by tissue engineered bone. There was no treatment in the blank group. Each 5 rabbits were sacrificed at weeks 2, 4, 8 and 12 after operation. The vascular area and biomechanical property of implanted bone were observed. RESULTS AND CONCLUSION: In the experimental and control groups, there were massive blood circulation with large vascular area at 4 weeks after operation, which trend to normal level at 12 weeks. The differences of vessel sizes between the experimental, control and blank groups had dramatically significance (P < 0.05). Compared with the control group, the vascular network ranged regularly, which similar to normal bone tissues at 12 weeks. The results demonstrated that tissue engineered bone has better vascularization and biomechanics property. It is a better way to repair bone defects.