Biomimetic Pericellular Microniche Inspired by Chondron enhances the Cartilage Matrix Accumulation

Abstract

AbstractCartilage repair is currently an inevitable and significant issue due to the prevalence of cartilage defects or osteoarthritis. However, it remains a big challenge worldwide because of the avascular and aneural nature of cartilage. In this paper, a novel biomimetic pericellular microniche (BPM), inspired by chondron composed of chondrocyte and its surrounding pericellular matrix (PCM), is proposed to offer a promising solution to achieve cartilage repair. BPM, with a diameter ≈64 µm, not only mimicked the structure of the chondron but also mimicked the key components of the PCM by artificially synthesizing brush‐like molecules hyaluronic acid‐grafted‐(poly‐2‐acrylamide‐2‐methylpropanesulfonic acid sodium salt) (HA/PA) and hyaluronic acid‐grafted‐(poly‐2‐methacryloyloxyethyl phosphorylcholine) (HA/PM). Chondrocyte‐laden BPM is constructed successfully through microfluidic and showed excellent injectability. The encapsulated chondrocyte showed high viability in BPM. F‐Actin and H&E reflected that chondrocytes would grow out of BPM and adhere to the BPM surface through the interaction between CD44 and hyaluronic acid. RT‐qPCR and immunofluorescence staining indicated that the gene expression of type II collagen and aggrecan are upregulated significantly in the BPM. Therefore, the construction of BPM provides a promising strategy for cartilage tissue engineering.