A Comprehensive Review of Auto- and Allogeneic Chondrocyte Transplantation in Animals and Humans From 1965 to 2025

ObjectiveTo review the history of chondrocyte transplantation, new approaches to treatment of human chondral and osteochondral defects, animal experiments, the choice of chondrocytes for transplantation, immunological features of human and animal chondrocytes and factors which could influence results of chondrocyte transplantation.DesignAs the material for review served numerous papers collected during our many years' chondrocyte studies supplemented by PubMed search.ResultsAutologous chondrocytes, expanded in culture, were successfully used to repair damaged human articular cartilage. Numerous modifications of the original procedure benefited from a better understanding of factors influencing chondrocyte differentiation. Immunological studies suggested that survival of allogeneic transplants of bioengineered human neocartilage may depend on both passive and active mechanisms of immune evasion. Human chondrocytes with deleted expression of MHC class I molecules produced cartilage which, after transplantation into monkey articular cartilage was attacked by NK cells.ConclusionsImmune response against human chondrocytes requires further investigation. It is already established that allogeneic chondrocytes are safe for treating chondral defects but not for healing osteochondral defects. Full reconstruction of cartilage defects by restoring anatomically identical hyaline cartilage seems not feasible.