含孔磷酸钙陶瓷复合自体成骨细胞骨组织工程大鼠模型的构建

A rat model of bone tissue engineering with autogenous osteoblasts loading on porous calcium phosphate bioceramic scaffolds

目的 构建封闭群动物SD大鼠骨组织工程模型 ,研究含孔磷酸钙陶瓷为支架复合自体成骨细胞的异位骨形成和极量骨缺损修复能力。方法 成年雄性SD大鼠 2 0只 ,全麻及无菌条件下取其左侧股骨及胫骨 ,将骨髓冲入 75ml培养瓶中并在诱导培养条件下进行体外扩增分化 ;培养 1 4d后将已具成骨细胞表型的细胞消化接种于经纤连蛋白表面修饰的含孔磷酸钙陶瓷上继续培养 1 5d ,再对应地将细胞 陶瓷复合体种植于大鼠皮下、肌肉内并用于颅骨极量缺损修复。分别于 2～ 2 0周处死动物 ,从形态学及组织学角度观察比较异位骨形成及骨缺损修复情况。结果 细胞 陶瓷复合体无论种植于皮下或肌肉内均表现明显的异位骨形成能力 ;颅骨极量缺损修复也优于同期仅植入经表面修饰但无细胞的陶瓷对照组。结论 应用封闭群动物SD大鼠构建的骨组织工程模型避免了采用免疫缺陷动物及同源近交系动物价格昂贵、近交衰退等缺点 ,其结果接近于临床 。

Objective To investigate the ability of heterotopic osteogenesis and reconstruction of critical size calvarial defect, a bone tissue engineering Sprague Dawley rat model with autogenous osteoblasts loading on porous calcium phosphate ceramic was established. Methods Bone marrow was obtained from femurs and tibias of 20 male adult SD rats under general anesthesia and sterile condition. Autogenous osteoblasts proliferated and differentiated in α minimal essential medium with some special additives for 14 days. Culture cells were then seeded and subcultured for another 15 days in porous calcium phosphate bioceramic, which had been soaked in fibronectin for surface modification. The cell ceramic compound was implanted subcutaneously and intramuscularly as well as used to repair critical sized (8 mm diameter) calvarial defect in the same rat. Lab animals were sacrificed at two week intervals till 20th week postoperatively and all the samples were dissected.Results Morphological and histological study demonstrated that cell ceramic compound had the ability of heterotopic osteogenesis. It was also observed that reconstruction of critical size calvarial defect with this hybrid material was better than that with solitary ceramic.Conclusion It seems that the experimental results got from this closed colony animal model were more similar to clinical situation. This model is superior to other homogenic or immune deficiency ones.