Exosomes to exosome-functionalized scaffolds: a novel approach to stimulate bone regeneration

Bone regeneration is a complex biological process that relies on the orchestrated interplay of various cellular and molecular events. Bone tissue engineering is currently the most promising method for treating bone regeneration. However, the immunogenicity, stable and cell quantity of seed cells limited their application. Recently, exosomes, which are small extracellular vesicles released by cells, have been found to effectively address these problems and better induce bone regeneration. Meanwhile, a growing line of research has shown the cargos of exosomes may provide effective therapeutic and biomarker tools for bone repair, including miRNA, lncRNA, and proteins. Moreover, engineered scaffolds loaded with exosomes can offer a cell-free bone repair strategy, addressing immunogenicity concerns and providing a more stable functional performance. Herein, we provide a comprehensive summary of the role played by scaffolds loaded with exosomes in bone regeneration, drawing on a systematic analysis of relevant literature available on PubMed, Scopus, and Google Scholar database.