Proteomic profiling of tear fluid: Implications for onset and severity of retinopathy of prematurity

Abstract

Purpose : Tear fluid, easily and noninvasively collected in infants, emerges as a promising biomarker source for retinopathy of prematurity (ROP). This study aims to scrutinize distinctive proteomic profile in tear fluid concerning the onset and severity of ROP.

Methods : Employing a retrospective cohort design, the study included 116 infants with 116 eyes admitted to the neonatal intensive care unit at Tottori University Hospital from 2019 to 2023. Of these, 56 eyes were ROP-naive, while 60 eyes were in the ROP-affected group. Among the ROP-affected eyes, 24 were severe ROP, necessitating treatment following Early Treatment for ROP study guidelines, and 36 were mild ROP, not requiring treatment. Tear fluids were collected from severe ROP eyes before treatment. Subsequently, tear fluid samples underwent extraction of exosomes, followed by mass spectrometry analysis. Proteomic profiles related to the onset and severity of ROP were analyzed using Ingenuity Pathway Analysis software.

Results : Proteomic analysis identified 1,866 proteins in the extracted tear fluid exosomes. Among these, 45 proteins exhibited a 1.5-fold higher expression in the tear fluid of ROP-affected (mild and severe) eyes compared to ROP-naive eyes. The proteins elevated in ROP-affected eyes included vimentin, Cu/Zn-superoxide dismutase, and creatine kinase B. Network analysis confirmed vascular endothelial growth factor A as a key player in the network related to ROP onset. Moreover, top canonical pathways related to ROP onset included neutrophil degranulation, while those related to severity requiring treatment included activation of matrix metalloproteinases and degradation of the extracellular matrix.

Conclusions : The proteomic profile of tear fluid may provide insights into mechanisms related to the onset and severity of ROP. These findings suggest the potential of tear fluid proteomic profiles as a noninvasive liquid biopsy for assessing ROP.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.