Combining gelatin methacryloyl hydrogels with mesenchymal stem cells: A versatile approach for bone tissue engineering.

Bone tissue engineering (BTE) represents an innovative strategy for repairing bone defects by integrating biomaterials, cells, and bioactive factors, aiming to mimic the structural and functional properties of natural bone tissue to facilitate regeneration. Bone healing is a multi-stage process involving inflammation, soft callus formation, hard callus development, and bone remodeling, which are regulated by the synergistic action of various cells and molecular signaling pathways. Gelatin methacryloyl (GelMA) hydrogel scaffolds, with their excellent biocompatibility, tunable mechanical properties, and photocrosslinking ability, provide a three-dimensional (3D) microenvironment similar to the natural extracellular matrix for cells. In recent years, combining mesenchymal stem cells (MSCs) with GelMA hydrogels has become a cutting-edge strategy for bone regeneration. GelMA not only supports the survival and proliferation of MSCs but also promotes osteogenic differentiation and accelerates bone defect repair through its adjustable physicochemical properties. This review, based on current literature, explores the unique properties of MSCs and the latest advancements in the synergistic effects of MSCs and GelMA hydrogels in promoting bone regeneration.