骨髓间充质干细胞与软骨细胞体外构建软骨的比较研究

Comparation of the chondrogenic ability between bone marrow mesenchymal stem cells and chondrocyte for in vitro engineering cartilage

目的探讨骨髓间充质干细胞(BMSCs)与软骨细胞的体外软骨形成规律及二者软骨形成质量的差异,为BMSCs临床应用转化提供参考依据。方法分别将猪的BMSCs及软骨细胞复合可降解支架进行体外软骨构建,体外构建2、4及8周后,取材行大体及组织学检测。以Ⅱ型胶原免疫组化及番红O染色法分别检测Ⅱ型胶原和蛋白多糖的表达情况,用ELISA及阿利新兰法测定Ⅱ型胶原及蛋白多糖含量,评估各组的软骨形成规律和形成质量。结果体外4周时BMSCs形成了软骨样细胞,并表达软骨相关的Ⅱ型胶原和蛋白多糖,但其Ⅱ型胶原和蛋白多糖含量显著低于软骨细胞组;8周时BMSCs形成了成熟的软骨组织,并具有典型的软骨陷窝结构,其在组织结构及生化组成上与软骨细胞组十分接近。结论 BMSCs的体外软骨形成速度较软骨细胞慢,但延长体外诱导时间可显著减小二者在组织结构及生化组成上的差异。

Objective To investigate the cartilage formation process of both bone marrow mesenchymal stem cells (BMSCs) and auricular chondrocyte and to evaluate the cartilage function of them, so as to provide detailed insights for future clinical applications of BMSCs. Methods BMSCs and auricular chondrocytes were respectively seeded on biodegradable scaffolds to engineer cartilage in vitro. At various time points from 2 to 8 weeks, engineered cartilage were grossly examined and harvested for biochemical evaluations (Safranin O and collagen Ⅱ immunohistochemical staining for qualitative evaluation of GAG and collagen Ⅱ;alcian blue and ELISA for quantitative analysis of GAG and collagen Ⅱ). Results At 4 weeks, BMSCs formed cartilage-like tissue and expressed cartilage-specific matrices, but its collagenⅡ and GAG content was significantly lower than that of chondrocyte group. At 8 weeks, BMSCs formed mature cartilage with typical lacuna structures, which was very similar to the chondrocyte group in terms of tissue structure and biochemical component. Conclusions Although the cartilage formation of BMSCs was slower than that of chondrocyte group, the inferiority of BMSCs would significantly reduce by extending in vitro chondrogenic induction time.