Bonding of meniscal tissue: a nude mouse repair model.

Meniscus repair is a current clinical challenge. Menisci play a fundamental role in knee biomechanics, but they lack intrinsic regenerative properties. Conse quently, when a tear occurs and the meniscus is removed surgically, even partially, crucial changes in knee homeostasis take place, often leading to the development of early osteoarthritis. In recent decades tissue engineering approaches have been advocated to improve the reparative processes of joint tissues. In this study, the bonding capacity of isolated chondrocytes was analysed in a nude mouse meniscus repair model: a swine chondrocyte-fibrin glue suspension was utilised as a biologic glue to improve bonding between two meniscal slices obtained from swine menisci. The composites were wrapped with acellular fibrin glue and implanted in subcutaneous pouches of nude mice for four weeks. Upon retrieval, a firm gross bonding was observed. This was consistent with the histological findings. In particular, a fibrocartilaginous tissue was found at the interface between the meniscal slices, having some penetration buds arising from the neo-tissue. These results demonstrated the potential of this model for improving meniscal bonding. However, further orthotopic studies in a large animal model are needed to evaluate its feasibility in clinical practice.