摘要
目的：生物衍生骨具有天然骨组织的三维立体孔隙-网架结构，有利于种子细胞的黏附、增殖。观察猪松质骨支架/骨髓基质干细胞复合体在兔体内成骨及支架的降解。
方法：实验于2005-03/2006-12在中南大学湘雅医院中心实验室完成。选择健康家兔16只，3月龄左右，其中1只提供骨髓，另15只作组织工程骨植入，分4，8，12周3个时间点，每个时间点5只。采用Ficoll密度梯度离心法得到兔骨髓基质干细胞并诱导培养；采用物理化学方法对猪松质骨进行处理得到猪松质骨支架，与经诱导培养的骨髓基质干细胞体外复合培养后植入机体内，同时植入单纯猪松质骨支架做自身对照。
结果：纳入动物15只，均进入结果分析。采用X射线、苏木精-伊红染色、Masson三色染色及图像分析观察猪松质骨支架/骨髓基质干细胞复合体在兔体内成骨及支架的降解。①X射线观察：猪松质骨支架/骨髓基质干细胞复合体移植术后4周移植区周围可见少量散在分布的中密度影，8，12周时中高密度影逐渐向中心区增大。单纯猪松质骨支架移植术后各时间点移植区内均呈低密度影。②组织学观察：猪松质骨支架/骨髓基质干细胞复合体植入后4周开始有新骨生成，支架开始降解；8周时新骨的形成及支架的降解都明显增加；12周时新骨继续增加，逐渐向成熟骨组织转变，可见少量哈佛系统，但骨小梁尚不典型，毛细血管增生明显，少量支架残留，未见炎症细胞。单纯猪松质骨支架植入后各时间点无新骨形成。③图像分析表明：猪松质骨支架/骨髓基质干细胞复合体植入后新骨组织随时间延长而增加，而材料组织随时间延长而减少，但新生骨组织增加与支架材料组织减少无明显直线相关（P > 0.05）。
结论：猪松质骨支架与骨髓基质干细胞复合移植后新骨逐渐形成，支架逐渐降解，是一种较理想的骨组织工程支架材料。
关键词：猪松质骨支架；骨髓基质干细胞；复合移植；成骨；生物材料

雷荣昌，翦新春.猪松质骨支架/骨髓基质干细胞复合体兔体内成骨[J].中国组织工程研究与临床康复，2008，12(10):1851-1855 [www.zglckf.com/zglckf/ejournal/upfiles/08-10/10k-1851(ps).pdf]

Osteogenesis of porcine cancellous bone scaffold/bone marrow stromal cells complex in rabbits

Abstract

AIM：Bio-derived bone possesses the three-dimensional pore-grid structure of natural bone tissues, and can improve the adhesion and proliferation of seed cells. This study was designed to investigate the osteogenesis and biological degradation of the porcine cancellous bone scaffold/bone marrow stromal stem cells complex in rabbits.
METHODS: This experiment was carried out from March 2005 to December 2006 in the Xiangya Hospital Center Laboratory of Central South University. Sixteen healthy rabbits, 3 months old, were recruited, and one rabbit was used for harvesting bone marrow while other 15 rabbits were randomly divided into three experimental groups for tissue-engineered bone implants at 4, 8 and 12 weeks, each group contained five rabbits. The bone marrow stromal stem cells of the rabbits were harvested with Ficoll density gradient centrifugation method for the induction of osteoblastic cells. Porcine cancellous bone scaffold was processed by physical and chemical methods, and compounded with bone marrow stromal cells cultured in vitro for the implantation. Meanwhile the implantation of single porcine cancellous bone scaffold was carried out as self-control.
RESULTS: Fifteen rabbits were involved in the analysis of results. X-ray, hematoxylin-eosin stain, Masson trichrome stain and image analysis were used to observe osteogenesis and degradation of porcine cancellous bone scaffold/bone marrow stromal stem cells complex in rabbits.①X-ray observation: A little medium density shadow distributed around the composite 4 weeks after implantation, and medium-high density shadow gradually enlarged to the centre area of the scaffold 8 and 12 weeks after implantation. There was a medium density shadow in the single scaffolds 4, 8, 12 weeks after implantation.②Histological observation: Four weeks after implantation, porcine cancellous bone scaffold/bone marrow stromal cells complex appeared new bone formation and scaffold's degradation, which significantly increased in 8 weeks; In 12 weeks, new bone continued to increase and changed gradually to mature bone, a small amount of the Havers system was seen, the trabecular bone was not typical, capillary proliferated obviously, few residual scaffolds were seen, and no inflammatory cells were observed. Single porcine cancellous bone had no new bone formation after implantation in each time point.③Image analysis: With the time prolonged, the new bone tissue increased, but the scaffold material reduced. There was non-linear correlation between the increase of new bone tissue and the decrease of scaffold material (P > 0.05).
CONCLUSION: In porcine cancellous bone scaffold/bone marrow stromal stem cells complex after implantation, the new bone forms gradually and the scaffold degrades gradually, so the complex is an ideal scaffold for bone tissue engineering.

Lei RC, Jian XC.Osteogenesis of porcine cancellous bone scaffold/bone marrow stromal cells complex in rabbits.Zhongguo Zuzhi Gongcheng Yanjiu yu Linchuang Kangfu 2008;12(10):1851-1855(China)
[www.zglckf.com/zglckf/ejournal/upfiles/08-10/10k-1851 (ps).pdf]