Human dental pulp stem cell-derived exosomes decorated titanium scaffolds for promoting bone regeneration

Exosomes, nanoscale extracellular vesicles crucial for intercellular communication, hold great promise as a therapeutic avenue in cell-free tissue regeneration. In this study, we identified and utilized exosomes to adorn anodized titanium scaffolds, inducing osteogenic differentiation in human dental pulp stem cells (hDPSCs). The osteogenesis of hDPSCs was stimulated by exosomes derived from hDPSCs that underwent various periods of osteogenic differentiation. After purification, these exosomes were loaded onto anodized titanium scaffolds. Notably, the scaffolds loaded with exosomes deriving from osteogenic differentiated hDPSCs demonstrated superior bone tissue regeneration compared to those loaded with exosomes deriving from hDPSCs within 10-week. RNA-sequencing analysis shed light on the underlying mechanism, revealing that the osteogenic exosomes carried specific cargo, which is due to upregulated miRNAs (Hsa-miR-29c-5p, Hsa-miR-378a-5p, Hsa-miR-10b-5p and Hsa-miR-9-3p) associated with osteogenesis. And down-regulated anti-osteogenic miRNA (Hsa-miR-31-3p, Hsa-miR-221-3p, Hsa-miR-183-5p and Hsa-miR-503-5p). In conclusion, the identification and utilization of exosomes derived from osteogenic differentiated stem cells offer a novel and promising strategy for achieving cell-free bone regeneration.