Effect of hUCMSC-sEV-Loaded GelMA Microspheres on Pulp/Dentin Repair and Regeneration
摘要
This study evaluated the biocompatibility of small extracellular vesicles (sEVs) derived from human umbilical cord mesenchymal stem cells (hUCMSC) loaded in gelatin methacryloyl hydrogel microspheres (sEVs@GM-MS), and examined their effects on the proliferation and migration of human dental pulp stem cells (hDPSCs)/human umbilical vein endothelial cells (HUVECs), as well as their capacity to promote endothelial cell tube formation. Pulpotomy in a rat molar model was used to assess sEVs@GM-MS as a potential pulp-capping agent.
Methods:sEVs@GM-MS were prepared and physicochemically characterized. In vitro assessments included live/dead staining, Cell Counting Kit-8 (CCK-8), migration assay and tube formation assay. In vivo, 7 and 14 days after pulpotomized with sEVs@GM-MS, GM-MS, iroot BP or without any pulp capping material, rat molars were evaluated using hematoxylin and eosin (H&E), Masson’s trichrome, and immunohistochemical (IHC) staining.
Results:GM-MS exhibited a porous surface via scanning electron microscopy. PKH67-labeled sEVs@GM-MS showed sustained release of sEVs. The cell proliferation, migration, tube formation in the sEVs@GM-MS group were significantly enhanced compared with those of the NC and GM-MS groups (p < 0.05). In rat pulpotomy model, sEVs@GM-MS group exhibited significant cell proliferation, angiogenesis, and reparative dentinogenesis with immunocytochemical localization of PCNA, CD31 and DMP-1 compared to NC and GM-MS groups (p < 0.05). Compared with the BP group, the sEVs@GM-MS group showed no significant difference in DMP-1 positive expression (p > 0.05).
Conclusion:sEVs@GM-MS demonstrated excellent biocompatibility, sustained hUCMSC-sEV release, and enhanced pulp/dentin repair and regenaration, highlighting their potential as a pulp-capping agent.