Biomimetic Approaches for the Engineering of Osteochondral Tissues

Abstract

Osteochondral defects induced by trauma or pathology remain a big challenge in orthopedics. These defects comprise injuries in both the articular cartilage and the subchondral bone. Due to the limited regeneration ability of articular cartilage, this kind of defects is normally irreparable and would gradually deteriorate toward osteoarthritis which requires surgical intervention. The current clinical treatments for osteochondral defects, such as total joint replacement and osteochondral autograft transplantation, are not ideal long-term solutions for this problem. Tissue engineering and regenerative medicine provides a possible and prospective curative strategy for this clinical hinder. Nevertheless, In order to successfully solve this problem, there are still many basic and critical questions must be answered. These include the optimization on scaffold’s composition and structure, selection of suitable cell source, modulation of primary/stem cell fate or engineered osteochondral tissue, incorporation of bioactive factors, and spatial regeneration of the chondral layer, subchondral layers and the interface. Biomimetic strategy has been employed to explore these fields and exciting progresses have been achieved. This chapter summarizes these interesting advances of the pre-clinical studies on engineering of osteochondral tissue in the last 5 years. Special attentions were given to the development of biomimetic layered scaffolds with dependences on composition, cell source, or bioactive factors. In addition, cell fate regulation, external stimuli and interface regeneration were discussed. New insights and promising directions for the future study in osteochondral regeneration were also provided.