Mesenchymal stem cell (MSC)-derived exosomes have shown potential as an effective therapeutic tool for repairing bone defects. In this study, we demonstrate that silk fibroin (SF) 3D-scaffolds enriched with MSC-derived exosomes successfully enhance bone regeneration in critical-sized rat calvarial defect areas. The exosomes coated on the SF scaffolds were not subjected to any chemical treatments or synthetic procedures to accelerate the osteogenic cellular processes modulated by the exosomes. Specifically, exosomes extracted from human adipose-derived mesenchymal stem cells (hAMSCs) were investigated for their capacity of inducing osteogenic differentiation and bone regeneration in vitro and in vivo. In vitro assay showed beneficial effect of the exosome-coated SF scaffolds on the growth and osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs). In vivo study confirmed thorough integration and attachment of implanted scaffolds in the bone defect region. These results indicate that SF scaffold coated with exosomes extracted from MSCs can be a suitable bone substitute graft for bone regeneration.

间充质干细胞（MSC）衍生的外泌体已显示出作为修复骨缺损的有效治疗工具的潜力。在这项研究中，我们证明，富含丝状蛋白（SF）的3D支架富含MSC衍生的外泌体，可以成功地增强关键尺寸大鼠颅盖缺损区域的骨再生。涂覆在SF支架上的外泌体未经过任何化学处理或合成程序以加速由外泌体调节的成骨细胞过程。具体而言，研究了从人脂肪来源的间充质干细胞（hAMSC）提取的外泌体在体外和体内诱导成骨分化和骨再生的能力。。体外测定显示外来体包裹的SF支架对人骨髓来源的间充质干细胞（hBMSC）的生长和成骨分化的有益作用。体内研究证实了植入的支架在骨缺损区域的彻底整合和附着。这些结果表明，涂​​有从MSC中提取的外泌体的SF支架可以是适合骨骼再生的骨替代移植物。