Stiffened fibre-like microenvironment based on patterned equidistant micropillars directs chondrocyte hypertrophy

作者：Mengmeng Duan, Shuang Xia, Yang Liu, Xiaohua Pu, Yukun Chen, Yilin Zhou, Minglei Huang, Caixia Pi, Demao Zhang, Jing Xie · 发表于：Materials Today Bio · 年份：2023 · DOI：10.1016/j.mtbio.2023.100682 · 被引用次数：22 · 研究领域：Osteoarthritis Treatment and Mechanisms、Cellular Mechanics and Interactions、Tendon Structure and Treatment

Articular cartilage, composed of collagen type II as a major extracellular matrix and chondrocyte as a unique cell type, is a specialized connective tissue without blood vessels, lymphatic vessels and nerves. This distinctive characteristic of articular cartilage determines its very limited ability to repair when damaged. It is well known that physical microenvironmental signals regulate many cell behaviors such as cell morphology, adhesion, proliferation and cell communication even determine chondrocyte fate. Interestingly, with increasing age or progression of joint diseases such as osteoarthritis (OA), the major collagen fibrils in the extracellular matrix of articular cartilage become larger in diameter, leading to stiffening of articular tissue and reducing its resistance to external tension, which in turn aggravates joint damage or progression of joint diseases. Therefore, designing a physical microenvironment closer to the real tissue and thus obtaining data closer to the real cellular behaviour, and then revealing the biological mechanisms of chondrocytes in pathological states is of crucial importance for the treatment of OA disease. Here we fabricated micropillar substrates with the same topology but different stiffnesses to mimic the matrix stiffening that occurs in the transition from normal to diseased cartilage. It was first found that chondrocytes responded to stiffened micropillar substrates by showing a larger cell spreading area, a stronger enhancement of cy...