College of Biological Science and Technology, Weifang Medical University, Weifang, 261053, China.
Department of Orthopaedics, Affiliated Hospital of Weifang Medical University, Weifang, 261042, China.
Biomed Pharmacother. 2019 Jul;115:108935. doi: 10.1016/j.biopha.2019.108935. Epub 2019 May 9.
Mesenchymal stem cells are ideal seed cell alternatives for articular cartilage tissue engineering, and the methods of the expansion of seed cells need to be improved. The mechanical factors play a significant role in the process of articular cartilage development and regeneration. The aim of this study was to improve the chondrogenic differentiation of mesenchymal stem cells and to expand seed cells for articular cartilage tissue engineering based on mechanical factors. Rabbit bone mesenchymal stem cells were subjected to cyclic dynamic square wave tensile mechanical loading using the FX-4000 tension system. The viscoelasticity of cells was investigated using the micropipette aspiration technique combined with the Kelvin standard linear viscoelastic solid model. The cell chondrogenic phenotype was assessed by detecting characteristic chondrocyte biomarkers; the expression of the GAG and TGF-β1 was analyzed by ELISA, and the expression of the Col2α1 and Sox9 gene was analyzed by RT-PCR. The results show that proper tensile mechanical stimulation improves the viscoelasticity and chondrogenic phenotype of mesenchymal stem cells such that it is similar to that of chondrocytes. These results suggest that viscoelasticity is a specific marker of chondrogenic differentiation and that proper mechanical stimulation culture methods can be used to expand seed cells and improve the chondrogenic phenotype for articular cartilage tissue engineering.
间充质干细胞是关节软骨组织工程理想的种子细胞替代物，种子细胞的扩增方法有待改进。力学因素在关节软骨发育和再生过程中起着重要作用。本研究旨在基于力学因素提高间充质干细胞的软骨分化能力，并扩增用于关节软骨组织工程的种子细胞。使用 FX-4000 张力系统对兔骨髓间充质干细胞进行循环动态方波拉伸机械加载。使用微管吸吮技术结合 Kelvin 标准线性粘弹性固体模型研究细胞的粘弹性。通过检测特征性软骨细胞生物标志物评估细胞的软骨细胞表型；通过 ELISA 分析 GAG 和 TGF-β1 的表达，通过 RT-PCR 分析 Col2α1 和 Sox9 基因的表达。结果表明，适当的拉伸机械刺激可提高间充质干细胞的粘弹性和软骨细胞表型，使其类似于软骨细胞。这些结果表明，粘弹性是软骨细胞分化的特异性标志物，适当的机械刺激培养方法可用于扩增种子细胞并提高关节软骨组织工程的软骨细胞表型。
