Transcriptome Profiling of TGFβ2 Treated Human Optic Nerve Head Astrocytes and Lamina Cribrosa Cells

Abstract

Purpose : The optic nerve head (ONH) is the initial site of optic nerve damage. ONH-derived astrocytes and lamina cribrosa (LC) cells synthesize proteins to support the ONH. However, ONH cells are adversely affected in glaucoma and cause detrimental changes to the ONH. Previous studies have shown increased expression of the profibrotic cytokine transforming growth factor-beta 2 (TGFβ2) in the glaucomatous ONH. In glaucoma conditions, TGFβ2 promotes dysregulated signaling through the canonical and non-canonical pathways. The purpose of this study was to determine the differential gene expression profile between control and TGFβ2 treated ONH astrocytes and LC cells using RNA sequencing (RNA-seq).

Methods : Primary human normal ONH astrocytes (n=3 strains) and LC cells (n=3 strains) were derived from human donor eyes. ONH cells were grown to confluency and treated with or without TGFβ2 (5ng/ml) for 24 hours. Total RNA was extracted from ONH cells and RNA sequence libraries were prepared and sequenced on an Illumina Miseq2000. RNA seq analysis was performed to identify significant differentially expressed genes and was tested for pathway enrichment analysis using WEB-based Gene SeT anaLysis Toolkit.

Results : RNA-seq and pathway analysis identified several significant enriched gene sets (FDR<0.05) for ONH astrocytes and LC cells. These differential expressed genes were involved in the extracellular matrix and ECM structural constituents such as disintegrin and metalloprotease family members, collagens, and periostin. Other gene sets included metabolism and steroid hormone biosynthesis such as alcohol dehydrogenase, aldehyde dehydrogenase, and cytochrome P450.

Conclusions : TGFβ2 modulates the expression of several genes in cultured human ONH astrocytes and LC cells that may be responsible for pathogenic remodeling of the optic nerve head in glaucoma. New therapeutic targets or small molecule inhibitors may be identified that stop or slow the pathogenesis of glaucoma.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.