A xenogeneic decellularized multiphasic scaffold for the repair of osteochondral defects in a rabbit model

Osteochondral defects involving cartilage and subchondral bone are difficult to repair. Recently, scientists have attempted to develop composite scaffolds for repair of osteochondral injuries. However, the avail-able composite scaffolds do not fully recapitulate the functions of the cartilage, subchondral bone, and cancellous bone. In this study, we developed a bioactive multiphase scaffold by decellularizing an intact osteochondral graft for osteochondral repair. The porosity and mechanical properties of the scaffolds were optimized using laser drilling and collagen digestion. The scaffold promoted the recellularization of the cartilage layer. The experimental results showed that the multiphasic scaffolds had excellent mechanical properties and structural stability similar to that of the normal rabbit osteochondral tissue. The in vitro analysis showed that the scaffold promoted zone-specific gene expression. Approximately 12 weeks after in vivo implantation, the multiphasic scaffold significantly facilitated the concurrent regeneration of cartilage and subchondral bone in a rabbit model (detected using gross and micro -computed tomography images, histological staining, immunohistochemistry, and visualization of the col-lagen network). Overall, this study provides ideas for the development of new multiphasic scaffolds for osteochondral defect repair.(c) 2022 The Authors. Published by Elsevier Ltd.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).