In this work, we describe a microfluidic three-dimensional (3D) chondrocyte culture mimicking in vivo articular chondrocyte morphology, cell distribution, metabolism, and gene expression. This has been accomplished by establishing a physiologic nutrient diffusion gradient across the simulated matrix, while geometric design constraints of the microchambers drive native-like cellular behavior. Primary equine chondrocytes remained viable for the extended culture time of 3 weeks and maintained the low metabolic activity and high Sox9, aggrecan, and Col2 expression typical of articular chondrocytes. Our microfluidic 3D chondrocyte microtissues were further exposed to inflammatory cytokines to establish an animal-free, in vitro osteoarthritis model. Results of our study indicate that our microtissue model emulates the basic characteristics of native cartilage and responds to biochemical injury, thus providing a new foundation for exploration of osteoarthritis pathophysiology in both human and veterinary patients.

在这项工作中，我们描述了模仿体内关节软骨细胞形态，细胞分布，代谢和基因表达的微流控三维（3D）软骨细胞培养。这是通过在整个模拟基质上建立生理养分扩散梯度而实现的，而微腔室的几何设计约束驱动了类似自然的细胞行为。马原代软骨细胞在延长的3周培养时间内仍保持活力，并保持了关节软骨细胞典型的低代谢活性和高Sox9，聚集蛋白聚糖和Col2表达。将我们的微流体3D软骨细胞微组织进一步暴露于炎症细胞因子，以建立无动物的体外骨关节炎模型。我们的研究结果表明，我们的微组织模型模仿了天然软骨的基本特征并对生化损伤作出了反应，从而为探索人和兽类骨关节炎的病理生理学提供了新的基础。