β-磷酸三钙-脱细胞软骨支架复合兔BMSCs修复膝关节软骨缺损的实验研究

Experimental study for the repair of knee-joint cartilage defects by using nano-tricalcium phosphate(N-TCP)artificial bone and bone marrow mesenchymal stem cells(BMSCs)

目的观察纳米磷酸三钙人工骨(β-TCP)、转化生长因子-β(TGF-β)、胰岛素样生长因子-Ⅰ(IGF-Ⅰ)、脱细胞耳软骨(DC)复合软骨细胞修复关节软骨缺损的效果。方法获取新西兰大白兔骨髓间充质干细胞(BMSCs),培养并体外诱导成软骨细胞,取异体兔耳软骨进行脱细胞处理,与β-TCP形成复合支架作为载体接种软骨细胞,加入TGF-β和IGF-I修复膝关节软骨缺损。实验动物(n=18)分为3组,实验组(n=8)复合支架加入TGF-β和IGF-I,对照组(n=6)仅以复合支架修复缺损,空白组(n=4)不加入任何修复材料。结果 BMSCs在体外生长稳定,增殖能力强,可被诱导为软骨细胞。软骨支架脱细胞完整,软骨陷窝排列有序,复合物植入缺损后第20周,实验组缺损内充填白色半透明新生软骨组织,色泽与正常软骨相似,与周围正常软骨连接良好。结论β-TCP-DC复合支架有较多的孔隙结构,降解速度快,组织相容性及细胞黏附性好,是组织工程修复关节软骨理想的种子细胞载体。

Objective To examine the effects of simultaneous application of Nano-Tricalcium phosphate （N-TCP） artificial bone and bone marrow mesencbymal stem cdls（BMSCs）plus the transforming growth factor-β （TGF-β） and insulin-growth factor-I（IGF-I） in repairing articular cartilage defects. Methods MSCs isolated from the bone marrow of New Zealand white rabbits were cultured in vitro and induced to chondrocytes. Auricular cartilages of allogenic rabbits were firstly decellularized and then integrated with N-TCP composite artificial bone in forming N-TCP-DC matrix scaffolds. Then the chondro- cytes were loaded into the scaffolds. TGF-βand IGF-Iwere added to repair the knee-joint cartilage defects. In experimental animals, 18 knee-joint articular cartilage defects were created, the defects were treated using N-TCP-DC matrix scaffolds with TGF-βand IGF-I（n =8） in comparison to controls of N-TCP-DC matrix scaffolds alone（n =6） and no engineered cartilage implants at all （n = 4）. Results BMSCs grew stably, reproduced vigorously and could be induced into chondrocytes in vitro. The auricular cartilages were completely decellulafized and the cartilage lacunae arrayed orderly. Around the 20th week, with the white translucent scaffold filling the articular cartilage defects, the newly formed cartilage in the experimental group connected well with the normal cartilage revealing similar color with that of the normal cartilage. Conclusion Being a porous structure, N-TCP-DC matrix scaffold is significant in regard to its rapid degradation ability, good histocompatibility and cell adhesive ability, making it a promising candidate for the cartilage tissue-engineering applications.