Biomimetic mineralized xenogenic acellular cartilage matrix promotes the repair of osteochondral defects and the recovery of motor function.

Abstract

Osteochondral lesion with subchondral bone cyst formation is clinically challenging. As the gold standard, autologous osteochondral transplantation has some problems such as limited source, donor-site complications and delayed subchondral bone reconstruction. In the study, a novel structurally biomimetic semi-biomineralized xenogeneic acellular costal cartilage matrix scaffold was developed to repair osteochondral lesion. This biomimetic scaffold with aligned lamellar structure possesses cartilage and subchondral bone components. It can promote endogenous cell penetration and the ingrowth of surrounding tissues. Then, its cartilaginous part and the mineralized part further promote the chondrogenic and osteoblastic differentiation of mesenchymal stem cells, respectively. The recovery of rat lower limb motor function in the biomimetic scaffold group was faster than that in control group, including the single standing time and crawling speed, and the crawling speed was restored faster than the positive control group (autologous costal cartilage transplantation). The regenerated bone volume and bone trabecular number in the biomimetic scaffold group were significantly higher than those in the positive control group, and the morphology of bone trabeculae was closer to normal. This biomimetic scaffold is a noninferior option to autologous costal cartilage transplantation for the treatment of osteochondral lesion.