Abstract
Cartilage lesions occur as a result of joint trauma, and progressively degenerate over time leading to osteoarthritis (OA). Early intervention therapies to repair the initial tissue damage have the potential to delay or prevent the onset of OA. We have developed two acellular treatments; 1) an injectable proteoglycan-like self-assembling hydrogel for the repair of ICRS grade 1 lesions, and 2) a decellularised xenogeneic osteochondral scaffold for surgical grafting in grade 2–4 lesions. We produced an in vitro glycosaminoglycan depleted grade 1 lesion model using porcine cartilage. Peptide-chondroitin sulphate mixture was injected and spontaneously gelled in situ. Cartilage resistance to deformation was increased by 50 %. Decellularised porcine osteochondral scaffolds which maintain the native tissue composition and architecture whilst being immunocompatible were successfully developed and are currently undergoing in vivo assessment in an ovine critical size condylar defect model. Incorporation of the subchondral bone in osteochondral scaffolds is intended to improve osseointegration; implanted decellularised bone-only scaffolds in sheep exhibited superb osteoinductive and osteoconductive properties in a proof-of-concept study. We envisage that our early intervention therapies will be employed clinically to maintain or restore functional hyaline-like cartilage across the whole range of early chondral pathologies and prevent the onset of OA.