Bioprinted biomimetic hydrogel matrices guiding stem cell aggregates for enhanced chondrogenesis and cartilage regeneration

作者：Yuetian Liu, Du Lijuan, Hua Zhang, Guanrong Li, Yang Luo, Zeming Hu, Rong Xu, Jie Yao, Zheyuan Shi, Y. Chen, Chi Zhang, Zhanping Jin, Caihua Zhang, Chanchan Xie, Jun Fu, Yabin Zhu, Yingchun Zhu · 发表于：Journal of Materials Chemistry B · 年份：2024 · DOI：10.1039/d4tb00323c · 被引用次数：14 · 研究领域：3D Printing in Biomedical Research、Bone Tissue Engineering Materials、Osteoarthritis Treatment and Mechanisms

Articular cartilage tissue has limited self-repair capabilities, with damage frequently progressing to irreversible degeneration. Engineered tissues constructed through bioprinting and embedded with stem cell aggregates offer promising therapeutic alternatives. Aggregates of bone marrow mesenchymal stromal cells (BMSCs) demonstrate enhanced and more rapid chondrogenic differentiation than isolated cells, thus facilitating cartilage repair. However, it remains a key challenge to precisely control biochemical microenvironments to regulate cellular adhesion and cohesion within bioprinted matrices simultaneously. Herein, this work reports a bioprintable hydrogel matrix with high cellular adhesion and aggregation properties for cartilage repair. The hydrogel comprises an enhanced cell-adhesive gelatin methacrylate and a cell-cohesive chitosan methacrylate (CHMA), both of which are subjected to photo-initiated crosslinking. By precisely adjusting the CHMA content, the mechanical stability and biochemical cues of the hydrogels are finely tuned to promote cellular aggregation, chondrogenic differentiation and cartilage repair implantation. Multi-layer constructs encapsulated with BMSCs, with high cell viability reaching 91.1%, are bioprinted and photo-crosslinked to support chondrogenic differentiation for 21 days. BMSCs rapidly form aggregates and display efficient chondrogenic differentiation both on the hydrogels and within bioprinted constructs, as evidenced by the upregulated ex...