Extracellular vesicles from induced pluripotent stem cell-derived periodontal ligament cells enhance proliferation and migration of periodontal ligament cells for periodontal regeneration.

BACKGROUND: Periodontal ligament (PDL) cells play a central role in periodontal tissue regeneration. We previously established induced pluripotent stem cell-derived PDL-like cells (iPS-PDL) as a potential alternative cell source for regenerative therapy. However, the properties and biological functions of extracellular vesicles (EVs) released by iPS-PDL remain unknown. Characterizing these EVs may facilitate the development of cell-free approaches for periodontal regeneration. OBJECTIVE: We aimed to isolate and characterize EVs derived from iPS-PDL (iPS-PDL-EVs) and compare their biological functions with those of primary PDL cell-derived EVs (PDL-EVs). METHODS: EVs were isolated and purified using size exclusion chromatography and characterized by nanoparticle tracking analysis, scanning transmission electron microscopy, nano flow cytometry, and Western blotting. Their effects on PDL cell proliferation and migration were evaluated using WST-8 and Transwell assays. miRNA sequencing and bioinformatic analyses were performed to identify differentially expressed miRNAs and enriched biological pathways. RESULTS: iPS-PDL-EVs and PDL-EVs exhibited typical EV characteristics. Compared with PDL-EVs, iPS-PDL-EVs significantly enhanced PDL cell proliferation and migration and activated MAPK and Akt signaling. Approximately 80% of the identified miRNAs were shared between the two EV populations; however, iPS-PDL-EVs contained elevated levels of miRNAs associated with MAPK signaling. miR-181a-2-3p suppressed IL1R1, whereas let-7i-5p and let-7g-5p suppressed FAS, thereby promoting PDL cell proliferation and migration. CONCLUSION: iPS-PDL-EVs exhibit superior regenerative activity compared with PDL-EVs and may promote periodontal regeneration through miRNA-mediated signaling. These findings support the potential of iPS-PDL-EVs as a cell-free therapeutic strategy for periodontal regeneration. Future in vivo studies are required to evaluate their therapeutic efficacy and safety.