APPLICATION OF SIZE-BASED SORTED ZONAL CHONDROCYTES FOR ARTICULAR CARTILAGE REPAIR

Abstract

The zonal property of articular cartilage endows the tissue with biphasic mechanical properties to withstand shearing force and compressional loading. Current treatments for articular cartilage damage are not able to restore the zonal organisation and functionality. In this study, a high-quality zonal chondrocyte production protocol integrating inertial spiral microchannel technology and dynamic microcarrier culture (dMC) was developed to address translational challenges in achieving zonal repair of articular cartilage in a clinical setting. Size-sorted zonal chondrocytes expanded on dMC were able to maintain the zonal cell size-phenotype relation, in contrast to expansion on a tissue culture plate. The post-expansion size-based sorting can be applied on dMC-expanded FT chondrocytes, generating zonal subpopulations that form phenotypically distinct cartilage constructs in 3D hydrogels. Six-month repair outcomes in a porcine chondral defect model showed that bilayered implantation of dMC-expanded zonal chondrocytes resulted in a substantial recapitulation of zonal architecture, accompanied by healthier underlying subchondral bone.