Extracellular vesicles in ophthalmology: innovations in diagnosis, therapy, and drug delivery

Most cells have the ability to secrete extracellular vesicles (EVs), which are nanoscale membrane-bound vesicles. EVs carry a diverse array of biomolecule, that play key roles in immunological modulation, intercellular communication, and the regulation of pathological and physiological processes. For EV-based diagnosis of ocular diseases, eye-derived biofluids serve as important sources. EVs found in these biofluids have emerged as promising biomarkers for the early detection of ocular diseases, as their molecular cargo can reflect the biology of their parent cells. Furthermore, due to their high biocompatibility and low immunogenicity, EVs have been explored as therapeutic agents and targeted drug delivery nanocarriers in various ocular diseases. In this review, we summarize the advancements in EV-based research focused on the detection and treatment of ocular diseases. We provide an overview of the origin of EV applications in ophthalmology, review techniques for isolating EVs from ocular biofluids, highlight EV bioengineering strategies for drug delivery, and present recent developments in EV-based diagnostics and therapeutics. Finally, we discuss ongoing clinical trials and conclude with an overview of the current challenges and future considerations for the clinical translation of EV-based approaches in ocular disease.