Wang Le, Pei Guo-Xian, Gao Liang-Bin, Jiang Shan, Mu Tian-Wang, Chen Si-Yuan, Qin Jun-Jun, Jin Dan, Lou Ai-Ju, Zhao Pei-Ran
Department of Orthopedic Surgery, Third Affiliated Hospital, Guangzhou Medical University, Third Affiliated Hospital, Guangzhou 510150, China.
Zhonghua Yi Xue Za Zhi. 2010 Jun 15;90(23):1637-41.
To investigate the effectiveness and mechanism of tissue engineering vascularized bone in repairing segmental femoral bone defects in rabbits.
Thirty-two rabbits were randomized into two groups (n = 16 each). A segmental and critical bone defect of 15 mm in length was made at left femur. In experimental group, the tissue engineering bone constructed from autologous bone marrow mesenchymal stem cells plus beta-tricalcium phosphate (beta-TCP) and vascular bundle was implanted into bony defect. In control group, there was no implantation of vascular bundle. Animals were sacrificed at 2, 4, 8 and 12 weeks post-implantation respectively. Histological observation was conducted to determine the process of new bone formation and remodeling. The expression of vascular endothelial growth factor (VEGF) in new bone was measured by immunohistochemistry, real-time PCR and Western blot.
As indicated by histological observations over time, new bone formation increased in both groups. It was better in the experimental group than the control group at the beginning of 4 weeks. The expression level of VEGF gradually decreased in each group after an initial rise. And the expression of VEGF was significantly higher than the control group after implantation at all time points and peaked at 4 weeks.
Tissue engineering vascularized bone accelerates bone repair in critical size defect model of femur in rabbit. Implantation of vascular bundle can promote the secretion of VEGF. And VEGF is an essential mediator of both angiogenesis and ossification.
探讨组织工程血管化骨修复兔股骨节段性骨缺损的有效性及机制。
将32只兔随机分为两组（每组n = 16）。在左股骨制造一个长度为15 mm的节段性临界骨缺损。实验组将由自体骨髓间充质干细胞加β-磷酸三钙（β-TCP）和血管束构建的组织工程骨植入骨缺损处。对照组不植入血管束。分别在植入后2、4、8和12周处死动物。进行组织学观察以确定新骨形成和重塑过程。通过免疫组织化学、实时PCR和蛋白质印迹法检测新骨中血管内皮生长因子（VEGF）的表达。
随着时间的组织学观察表明，两组新骨形成均增加。在4周开始时，实验组优于对照组。VEGF表达水平在每组初始升高后逐渐下降。并且在所有时间点植入后VEGF的表达均显著高于对照组，并在4周达到峰值。
组织工程血管化骨可加速兔股骨临界尺寸缺损模型中的骨修复。植入血管束可促进VEGF的分泌。并且VEGF是血管生成和骨化的重要介质。
