Correlation between fibronectin, connective tissue growth factor and periostin in preretinal fibrovascular proliferation

Abstract

Purpose : Our previous study revealed that periostin (PN) plays a major role in preretinal fibrovascular proliferation. We also showed that the gene expression level of fibronectin (FN) and connective tissue growth factor (CTGF) was elevated in preretinal membranes from eyes of proliferative vitreoretinopathy patients by genome-wide gene expression profiling. The purpose of this study was to determine the correlation among FN, CTGF and PN in preretinal fibrovascular proliferation.

Methods : PN was overexpressed in human retinal pigment epithelial cells (hRPEs), and PN-protein complex was extracted. We performed mass spectrometry to determine the protein components binding to PN. Real time RT-PCR was performed to determine the level of mRNA of PN, FN and CTGF from hRPEs and fibrovascular membranes (FVMs) obtained from patients with proliferative diabetic retinopathy (PDR) by vitrectomy. We also measured expression levels of these proteins in vitreous of PDR patients by enzyme-linked immunosorbent assay (ELISA). Immunostaining of FVMs from PDR patients and from the mouse model of oxygen-induced retinal neovascularization (OIR) was performed.

Results : By mass spectrometry, the expression level of FN in the protein complex was elevated (score 1950, match 74). The expression levels of PN, FN and CTGF mRNA in the FVMs were significantly higher than those in control samples (p＜0.05). The mRNA levels of PN, FN and CTGF increased and peaked at twelve, twelve and three hours, respectively, after TGF-β stimulation. The protein levels of vitreous humor were significantly correlated between FN, CTGF and PN (p＜0.001, ρ=0.75, p＜0.01, ρ=0.48, respectively). FN, CTGF and PN was co-stained in the alpha-SMA positive cells in FVMs.

Conclusions : These results indicate that CTGF and FN interact with PN and regulate the formation of preretinal FVMs.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.