3D Printing of Cobalt-Incorporated Chloroapatite Bioceramic Composite Scaffolds with Antioxidative Activity for Enhanced Osteochondral Regeneration.

Osteochondral defects are often accompanied by excessive reactive oxygen species (ROS) caused by osteoarthritis or acute surgical inflammation. An inflammatory environment containing excess ROS will not only hinder tissue regeneration, but also impact the quality of newly formed tissues. Therefore, there is an urgent need to develop scaffolds with both ROS scavenging and osteochondral repair functions to promote and protect osteochondral tissue regeneration. In this work, by using 3D printing technology, we developed a composite scaffold based on cobalt-incorporated chloroapatite (Co-ClAP) bioceramics, which possessed ROS-scavenging activity and could support cell proliferation, adhesion, and differentiation. Benefiting from the catalytic activity of Co-ClAP bioceramics, the composite scaffold could protect cells from oxidative damage under ROS-excessive conditions, support their directional differentiation, and simultaneously mediate an anti-inflammatory microenvironment. In addition, it was also confirmed by using rabbit osteochondral defect model that the cobalt-incorporated chloroapatite/Poly (lactic-co-glycolic acid) (Co-ClAP/PLGA) scaffold could effectively promote the integrated regeneration of cartilage and subchondral bone, exhibiting an ideal repair effect in vivo. This study provides a promising strategy for the treatment of defects with excess ROS and inflammatory microenvironments. This article is protected by copyright. All rights reserved.