摘要
目的观察用BMP7修饰前后的骨髓基质干细胞修复羊股骨缺损效果的差异,探讨用组织工程与基因工程相结合的方法修复长骨缺损,为临床研究打下基础。方法分别用含有地塞米松(10～8M,Sigma)、β-磷酸甘油钠(10mM,Sigma)的DMEM培养的骨髓基质干细胞(组1,n=7)和Adeno-BMP7转染的骨髓基质干细胞(组2,n=7)与珊瑚复合,再分别用于修复股骨缺损,通过不同时间点的X线观察、组织学观察和灰度分析来评价骨缺损的程度。结果组1X片显示4月前新生骨密度逐渐增高;八月时,骨缺损处新生骨转化为新生皮质骨。组2X片显示在3月前就有大量新生骨形成,新生皮质骨形成时间明显早于组1。由于组2新生骨形成的体积较大,X片灰度分析与组1相比并没有显著性差异。结论两种方法都能修复羊股骨缺损。BMP7局部基因转染的方法有利于骨组织再生。
Objective This study investigated the efficacy of tissue-engineered bone （osteogenie induced and BMP7 genetic modified BMSCs in a carrier of coral） in healing segmental defect of sheep femur. The objective was to explore one way of repairing long bone defect with tissue-engineering and molecular biology, and apply it in the future to the treatment of bone defect in clinic. Methods Isolated sheep BMSCs were in vitro induced with DMEM containing 10%FBS, 10-8M dexamethasone and 10mM 13-phosphoglycerol, or infected with BMP-7 adenovirus （100 pfu/cell）. Defect in right femur were either repaired with coral construct plus induced cell （groupl, n=7） or construct plus BMP7 modified cells （group2, n=7）. Bone healing was monitored by radiograph and histology at various time points and radiodensity quantification （F-test）. Results In the defect by radiology, new bone was formed during months 1 to 4 with increased radiodensity in groupl, Engineered bone was remodeled into cortex bone at 8 months, abundant callus was formed in group2 as early as month 3, and the engineered bone was remodeled into cortex bone earlier than that of groupl. Although the radiodensity was higher than that of coral compounded with induced BMSCs, but there was not significantly difference （p=0.054）, which could be explained for large vary of new bone formed in the implants of coral compounded with Adeno BMP7 infected BMSCs. Conclusion This study demonstrated that long bone tissue can be successfully engineered in sheep using induced or BMP7-genetic modified BMSCs and coral, and elicited the healing of critical-sized segmental bone defects in sheep. This local, or regional, approach to gene therapy may be particularly suitable for bone regeneration.
出处
《组织工程与重建外科杂志》
2007年第2期72-76,共5页
Journal of Tissue Engineering and Reconstructive Surgery
