Creating a living hyaline cartilage graft free from non-cartilaginous constituents : an intermediate role of a biomaterial scaffold

A novel living hyaline cartilage graft (LhCG) with controllable dimensions and free of non-cartilaginous constituents for articular regeneration is developed. As a living graft for regenerative medicine, LhCG is purely living tissue based and truly scaffold-free. The process of neotissue formation in LhCG is mediated by an interim biomaterial-based novel scaffolding system. This design highlights a philosophy of using biomaterials in engineered regenerative medicine as a transient guiding facility rather than a permanent part of substitute. The fabrication is designed and practiced in a continuous and integrated process, which attributes to its simplicity in operation. Because of the intrinsic non-cell-adhesive property of hydrogel scaffolds, articular chondrocytes’ phenotype is always preserved throughout the whole procedure, which has been tested and approved both in vitro and in vivo. In situ grafting trials in a rabbit model showcase high success rates in both cartilage repair and graft-host integration. Beyond cartilage repair, this LhCG model may provide a living-tissue-based open platform or niche for multi-tissue regenerations.