Promoting Stem Cell Mechanosensing and Osteogenesis by Hybrid Soft Fibers.

Bone regenerative biomaterials are essential in treating bone defects as they serve as extracellular matrix (ECM) mimics, creating a favorable environment for cell attachment, proliferation, and differentiation. However, the currently used bone regenerative biomaterials mostly exhibit high stiffness, which may lead to difficulties in degradation and thus increase the risk of foreign body ingestion. In this study, we prepared soft fibrous scaffolds modified with Zn-MOF-74 nanoparticles via electrostatic spinning. The soft fibers (only 1 kPa) permit remodeling under cellular adhesive force, optimizing the mechanical cues in the microenvironment to support cell adhesion and mechanosensing. In addition, the incorporation of Zn-MOF-74 nanoparticles enables the stable and sustained release of zinc ions, promoting stem cell mechanotransduction and osteogenic differentiation. Therefore, the hybrid soft fibers facilitate the regeneration of new bone in the rat femoral defect model, which provides a promising approach for regenerative medicine.