Shi Yang, Ma Jingyun, Zhang Xu, Li Hongjing, Jiang Lei, Qin Jianhua
Department of Biotechnology, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
Integr Biol (Camb). 2015 Mar;7(3):289-97. doi: 10.1039/c4ib00273c. Epub 2015 Jan 23.
Controlling the chondrocyte phenotype and function in a physiologically relevant microenvironment remains a major challenge for cartilage repair in tissue engineering applications. This work presents a straightforward strategy to create a high throughput concave microwell array used for generating multicellular spheroids of chondrocytes and facilitating the maintenance of the articular chondrocyte phenotype and function by combining 3D spheroid culture with hypoxia. The polydimethylsiloxane (PDMS) concave microwells were simply produced from a concave SU-8 template fabricated using a soft-lithography approach and easily adopted for size-controlled spheroid culture. 3D spheroid culture was observed to facilitate the cartilage-specific phenotype and function maintenance as compared to 2D monolayer culture. Combining hypoxia with spheroid culture markedly increased the expressions of cartilage-specific collagen II and aggrecan at protein and mRNA levels. The hypoxia-inducible factor (HIF) signaling pathway was found to get involved in phenotype maintenance, metabolism and differentiation of chondrocytes by regulating HIF-1α and HIF-2α, respectively. The established approach provides a useful platform for a wide range of applications in the field of cartilage biology, stem cell research and high throughput 3D drug testing in cancer.
在生理相关的微环境中控制软骨细胞表型和功能仍然是组织工程应用中软骨修复面临的一项重大挑战。这项工作提出了一种直接的策略，即通过将三维球体培养与低氧条件相结合，创建一种用于生成软骨细胞多细胞球体并促进关节软骨细胞表型和功能维持的高通量凹形微孔阵列。聚二甲基硅氧烷（PDMS）凹形微孔是由使用软光刻方法制造的凹形SU-8模板简单制作而成，并且易于用于尺寸可控的球体培养。与二维单层培养相比，观察到三维球体培养有助于软骨特异性表型和功能的维持。将低氧条件与球体培养相结合，在蛋白质和mRNA水平上显著增加了软骨特异性胶原蛋白II和聚集蛋白聚糖的表达。发现低氧诱导因子（HIF）信号通路分别通过调节HIF-1α和HIF-2α参与软骨细胞的表型维持、代谢和分化。所建立的方法为软骨生物学、干细胞研究和癌症高通量三维药物测试领域的广泛应用提供了一个有用的平台。
