Investigating gene regulatory networks controlling retinal fibrosis in a rabbit model of proliferative vitreoretinopathy

Abstract

Purpose : Proliferative vitreoretinopathy (PVR) is a leading cause of surgical failure in retinal reattachment procedures, and there are currently no pharmacologic treatments for it. Despite its prevalence and impact, the molecular pathways underlying PVR initiation and progression are poorly understood. In this study, we aimed to identify the gene regulatory networks associated with PVR progression.

Methods : Animal procedures were conducted in accordance with the ARVO Statement for the Use of Animals in Ophthalmic and Vision Research and were approved by the Johns Hopkins Animal Care and Use Committee. Unilateral retinal injury was induced in Dutch Belted rabbits through a combination of vitrectomy, retinotomy, retinal detachment, platelet-rich plasma injection, and cryotherapy. The transcriptional and epigenetic profile of extracted retinas from injured and control eyes was then assessed at different time points after injury using single cell/single nuclei RNA-sequencing (sc/sn-RNAseq) and single cell ATAC-sequencing (scATAC-seq).

Results : Retinas were harvested at time points ranging from 4 hours to 35 days after injury induction. We profiled >200,000 individual transcriptomes and chromatin accessibility from >40,000 cells. All major retinal cells including neurons, glia, and retinal pigment epithelium cells were identified in the data sets using selected marker genes. We identified various stages of glial cells post-injury and the transcriptional regulatory networks controlling them.

Conclusions : Our high-throughput transcriptomic analysis identified several known reactive, fibrotic, and neurogenic pathways that were induced after injury. These findings may aid in future research on the molecular pathways that could be targeted for potential pharmacological modulation.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.