Proposed underlying mechanisms of iPSCs/MSCs-Exos in corneal epithelial defect healing. We propose that both iPSCs-Exos and MSCs-Exos can promote corneal epithelial repair and regeneration by enhancing HCECs proliferation, migration, promoting cell cycle development and attenuating apoptosis. iPSCs-Exos showed stronger effect on HCECs than MSCs-Exos in all aspects.