Tear extracellular vesicles are nanoscale vesicles released from cells in the eye that can carry a variety of biomolecules, such as proteins, RNA, DNA, metabolites, and liposomes. Tial extracellular vesicles can be used as a sample of liquid biopsy for the detection and diagnosis of ocular and systemic disease. Tial extracellular vesicles can transmit signals and effector molecules between cells to regulate ocular physiological functions and immune responses. Tear extracellular vesicles can be used as a novel therapeutic vehicle for the delivery of drugs or genes to the eye. Because of their good biocompatibility, penetration and targeting, they can effectively deliver drugs or genes to specific sites or cells in the eye, enhancing therapeutic efficacy and reducing side effects.

Exosomes were isolated from tears of healthy people and dry eye patients, and proteomic analysis found that there were some proteins related to dry eye in tear exosomes of dry eye patients, such as corneal keratinization related protein, corneal epithelial barrier related protein, immune regulation related protein. These proteins can be used as biomarkers for dry eye diagnosis.