Exosomes in corneal diseases: advances in diagnosis and therapy

The diagnosis and treatment of corneal diseases still face many challenges. As nanoscale vesicles (30-150 nm in diameter), exosomes facilitate intercellular communication by transporting bioactive molecules such as proteins and nucleic acids. Exhibiting low immunogenicity, minimal toxicity, and engineering versatility, they hold strong promise for both diagnostic and therapeutic applications in corneal diseases. This review provides a comprehensive overview of the current understanding and future directions of exosome research in corneal diseases. We systematically compare traditional and emerging methods for exosome isolation and purification. We then discuss their expanding roles: (1) as diagnostic biomarkers and (2) as therapeutic agents or drug delivery systems, with an emphasis on representative examples and engineering innovations. Finally, we critically assess persistent challenges and outline essential research priorities for clinical translation. Looking forward, we highlight the need for standardized isolation protocols, large-scale production of clinical-grade exosomes, and targeted engineering strategies (e.g., surface modification or cargo loading) to enhance corneal wound healing and immune modulation. The integration of exosome-based therapies with biomaterials and sustained-release platforms may further unlock their potential, paving the way for personalized, off-the-shelf treatments for corneal disorders.