Evaluation of Dexamethasone-Eluting Cell-Seeded Constructs in a Preclinical Canine Model of Cartilage Repair.

In this 12-month long, preclinical large animal study using a canine model, we report that engineered osteochondral grafts (comprised of allogeneic chondrocyte-seeded hydrogels with the capacity for sustained release of the corticosteroid dexamethasone [DEX], cultured to functional mechanical properties, and incorporated over porous titanium bases), can successfully repair damaged cartilage. DEX release from within engineered cartilage was hypothesized to improve initial cartilage repair by modulating the local inflammatory environment, which was also associated with suppressed degenerative changes exhibited by menisci and synovium. We note that not all histological and clinical outcomes at an intermediary time point of three months paralleled 12-month outcomes, which emphasizes the importance of studies in valid preclinical models that incorporate clinically relevant follow-up durations. Together, our study demonstrates that engineered cartilage fabricated under the conditions reported herein can repair full-thickness cartilage defects and promote synovial joint health and function.