三维环境下软骨细胞诱导滑膜间充质干细胞向软骨样细胞的分化

Chondrocyte-like differentiation of synovial mesenchymal stem cells co-cultured with chondrocytes on a three-dimensional scaffold

背景:体外环境下软骨细胞与滑膜间充质干细胞共培养能够使滑膜间充质干细胞向软骨分化,关于体内环境下细胞共培养诱导干细胞分化的研究很少。目的:拟将滑膜间充质干细胞/软骨细胞与壳聚糖/Ⅰ型胶原复合支架材料植入大鼠背部皮下,了解细胞复合支架在体内向软骨分化的情况。方法:取SD大鼠膝关节滑膜组织及软骨组织,用酶消化法获得滑膜间充质干细胞及软骨细胞分别进行培养。实验设单纯软骨细胞组,单纯滑膜间充质干细胞组,滑膜间充质干细胞︰软骨细胞为1︰2组,无细胞材料组,取第3代滑膜间充质干细胞及第2代软骨细胞培养于壳聚糖/Ⅰ型胶原复合支架材料中移植于SD大鼠皮下,4,8周时取材进行苏木精-伊红染色、甲苯胺蓝染色和免疫组织化学检测。结果与结论:植入4,8周后,细胞支架材料保持圆盘状,单纯软骨细胞组、滑膜间充质干细胞︰软骨细胞为1︰2组可见细胞及细胞基质Ⅱ型胶原阳性表达,单纯软骨细胞组、滑膜间充质干细胞︰软骨细胞为1︰2组蛋白聚糖阳性表达,结果表明两种细胞混合培养于壳聚糖/Ⅰ型胶原复合支架材料中,在体内环境下能够形成软骨样组织。

BACKGROUND： The co-culture of chondrocytes and synovial mesenchymal stem cells can induce the cartilage differentiation of synovial mesenchymal stem cells in vitro, but the cell differentiation induced by co-culture in vivo is rarely reported.OBJECTIVE： To investigate the chondrogenic differentiation of synovial mesenchymal stem cells co-cultured with chondrocytes on the chitosan/type I collagen composite scaffolds after being transplanted into the subcutaneous layer of Sprague-Dawley rats. METHODS： The synovial mesenchymal stem cells and chondrocytes harvested from the synovial membrane and articular cartilage of Sprague-Dawley rats were obtained by enzyme digestion method and cultured respectively. Passage 3 synovial mesenchymal stem cells and passage 2 chondrocytes, which were divided into four groups： group A（chondrocytes alone）, group B（synovial mesenchymal stem cells alone）, group C（ratio of synovial mesenchymal stem cells：chondrocytes=1：2） and group D（scaffold material without cells）, were cultured on chitosan/type I collagen composite scaffolds and transplanted into the subcutaneous layer of rats followed by morphological observation and immunohistochemical staining at 4 and 8 weeks.. RESULTS AND CONCLUSION： After 4 and 8 weeks, the discoid-like scaffold was visible. The immunohistochemical staining of type II collagen and the toluidine blue staining of aggrecan were significantly positive in groups A and C. These results show that the co-culture of synovial mesenchymal stem cells and chondrocytes on the scaffold in vivo can form cartilage-like tissues.