中文摘要：

目的在体外建立稳定有效的软骨细胞分化模型。方法复苏ATDC5细胞，在倒置显微镜下观察细胞形态及其生长情况，细胞90％融合时分别用不含vc和含vc的诱导培养基培养进行分化诱导。诱导21d，阿力新蓝染色，RT-PCR检测Ⅱ、X型胶原表达进行鉴定。结果含50μg／mLVc的诱导培养基诱导1周便可见明显的软骨小结，细胞产生软骨基质明显增多，Ⅱ及X型胶原表达明显增高，且X型胶原表达呈提前。结论利用ATDC5细胞系可成功建立软骨细胞分化体外模型。

英文摘要：

Objective To set up a stable and effective model in vitro of chondrogenic differentiation. Methods ATDC5 cells were reanimated from liquid nitrogen, and cultured in the maintenance medium consisting of a 1 ： 1 mixture of DME and Ham＇s F-12 medium containing 5% FBS. The morphological changes and growth feature were observed under the inverted microscope each day. When ATDC5 cells rapidly proliferated to form 90 % confluency, the cells were cultured in differentiation medium supplemented with Vc or no Vc for 21 d. The extent of chondrogenie differentiation was examined by aleian blue staining and RT-PCR detection of the expression level of mRNA of type Ⅱ collagen and type X collagen. Results For ATDC5 cells cultured in differentiation medium containing 50 μg/ml Vc, cartilaginous nodules were detectable apparently at 7 d after chondregenic differentiation induction, the synthesis of glycosaminoglycans （GAGs） were increased, and the expression levels of type Ⅱcollagen and type X collagen mRNA were also upregulated, with earlier expression of type X collagen. Conclusion The method used in this work can provide an in vitro chondrogenic differentiation model.