藻酸钙凝胶复合骨髓间充质干细胞修复大鼠颅骨极量缺损

Repairing critical size calvarial defects in rats with the complex of bone marrow mesenchymal stem cells and alginate gel

背景:课题组前期已经发现藻酸盐凝胶/骨髓间充质干细胞复合物能在体内形成软骨,并能稳定分泌Ⅱ型胶原。目的:在前期工作的基础上,观察藻酸钙凝胶/骨髓间充质干细胞复合物修复大鼠颅骨极量缺损的效果。设计、时间及地点:配对对照观察实验,2004-01/2008-02在四川大学口腔疾病研究国家重点实验室完成。材料:将1.2%藻酸钠与骨髓间充质干细胞混匀后滴入氯化钙溶液,制备藻酸钙凝胶/骨髓间充质干细胞复合体。方法:SD大鼠24只,在其颅骨两侧各做一直径5mm的极量全层骨缺损,随机植入藻酸钙凝胶/骨髓间充质干细胞复合体(实验侧)及无细胞的藻酸钙凝胶(对照侧)。在术后4周和8周分别处死12只动物,取缺损植入处进行检测。主要观察指标:X射线检测成骨情况,苏木精-伊红染色及改良Masson三色染色观察组织学变化,透射电镜观察超微结构,同时进行Ⅰ型和Ⅲ型胶原免疫组织化学检测。结果:24只SD大鼠均进入结果分析。X射线检测发现,与对照侧相比,实验侧缺损的边缘有明显钙化密度增高表现。组织学、免疫组织化学检测均显示藻酸钙凝胶/骨髓间充质干细胞复合物中形成的组织呈现出交织状骨组织学特征,新骨量多而且结构酷似成熟骨。结论:藻酸钙凝胶/骨髓间充质干细胞复合物能用于修复颅骨极量骨缺损。

BACKGROUND： Based on the previous study, the complex of alginate gel and bone marrow mesenchymal stem cells （BMSCs） can induce chondrogenesis in vivo and secrete type Ⅱ collagen. OBJECTIVE： To investigate the effect of repairing a rat model of critical size caivarial defects using autogenous BMSCs and aiginate gel DESIGN, TIME AND SETTING： A paired controlled study was performed from January 2004 to February 2008 in State Key Laboratory of Oral Diseases, Sichuan University. MATERIALS： BMSCs were mixed with 1.2% algin and then added into the Calcium chloride solution to prepare the complex of BMSCs and alginate gel. METHODS： A total of 24 SD rats were used. Full thickness cranial plate defects at a diameter of 5 mm were created on the both sides of rat＇s skull. The complex of BMSCs and alginate gel （the experiment side） and only alginate gel （the control side） were implanted into the defects of 24 rats. After 4 weeks and 8 weeks postoperatively, the animals were sacrificed and the specimen were taken to make the examinations. MAIN OUTCOME MEASURES： Osteogenesis was determined using X-ray detection, histological examination was observed with hematoxylin-eosin stain and Masson trichrome stain, the ultrastructure was detected with transmission electron microscope, immunohistochemical examination of collagen Ⅰ and Ⅲ was also performed. RESULTS： All 24 animals entered the result analysis. X-ray results showed that compared with the control side, the defect verge of the experiment side had a significantly higher density of calcified performance. Histology and immunohistochemistry tests showed that the experiment side appeared the histological characteristics of interlace bone and a great amount of new bone, in which the structure resembled mature born. CONCLUSION： The complex of BMSCs and alginate gel can repair the critical size caivarial defect.