Highly Elastic and Anisotropic Wood-Derived Composite Scaffold with Antibacterial and Angiogenic Activities for Bone Repair.

Scaffold-based tissue engineering is a promising strategy to address the rapidly growing demand for bone implants, but developing scaffolds with bone extracellular matrix like structures, suitable mechanical properties and multiple biological activities remains a huge challenge. Here, we aimed to develop a wood-derived composite scaffold with anisotropic porous structure, high elasticity, and good antibacterial, osteogenic and angiogenic activities. First, natural wood was treated with alkaline solution to obtain a wood-derived scaffold with oriented cellulose skeleton and high elasticity, which can not only simulate collagen fiber skeleton in bone tissue, but also greatly improve the convenience of clinical implantation. Subsequently, chitosan quaternary ammonium salt (CQS) and dimethyloxalylglycine (DMOG) were further modified on the wood-derived elastic scaffold through a polydopamine layer. Among them, CQS endows the scaffold with good antibacterial activity, while DMOG significantly improves the scaffold's osteogenic and angiogenic activities. Moreover, the anisotropic and elastic characteristics of the scaffold can induce cell polarization and osteogenic activity through YAP/TAZ signaling pathway. Interestingly, DMOG can also activate the YAP/TAZ by upregulating the expression of Runx-2. That is to say, the mechanical characteristics of the scaffolds and the modified DMOG can synergistically enhance the expression of YAP/TAZ, thereby effectively promoting osteogenic differentiation. Therefore, this wood-derived composite scaffold is expected to have potential application in the treatment of bone defects. This article is protected by copyright. All rights reserved.