# Photoreceptor Determination of Retinal Blood Vessel Growth in Retinopathy

> **NIH NIH R01** · BOSTON CHILDREN'S HOSPITAL · 2021 · $429,225

## Abstract

PROJECT SUMMARY/ABSTRACT
Retinopathy of prematurity (ROP) is a major cause of blindness and disability in children. With advances in
neonatal care, smaller and more premature infants are saved who are at high risk for ROP. Therefore, the
incidence of ROP continues to increase. Current laser ablation surgery destroys retina and anti-VEGF (vascular
endothelial growth factor) treatment may cause systemic suppression of vessel growth in fragile neonates. The
long-term goal is to understand the molecular mechanisms of ROP development to devise earlier preventative
therapies. Inflammatory mediators are known key regulators in retinopathy but the causal link has been elusive
and standard anti-inflammatory drugs such as steroids or NSAIDS are not effective in ROP. Inflammation is often
thought to come from infiltrating inflammatory cells including macrophages, neutrophils and resident microglia.
But photoreceptors, which play an important role in the pathogenesis of ROP, also signal for blood vessel growth
through inflammatory proteins. The overall objective in this application is to identify how photoreceptors
determine blood vessel growth. We found that in photoreceptors, transcription factor c-Fos, an immediate early
gene and pro-oncogene, and a master regulator of many inflammatory factors, controls retinal angiogenesis by
modulating photoreceptor-derived inflammatory signals in a mouse model of retinopathy. c-Fos is found in the
human photoreceptor cells throughout their development. c-Fos is also important in regulating rod-specific gene
expression and photoreceptor apoptosis. Our preliminary data show that c-Fos is increased in photoreceptors
and that suppression of c-Fos in photoreceptors inhibits neovascularization in an oxygen-induced retinopathy
(OIR) mouse model of ROP. These findings suggest that c-Fos may be a major signaling pathway used by
stressed photoreceptors to convey the need for blood vessels and is a potential target to control the development
of neovascularization. We hypothesize that photoreceptors determine pathological retinal angiogenesis in ROP
by modulating the inflammatory signals via c-Fos. The rationale for the proposed research is that understanding
the molecular mechanisms of ROP development has the potential to help develop treatment of ROP (now
affecting ~16,000 US infants per year). We propose to test this hypothesis with three Aims. Aim 1: To determine
whether photoreceptor c-Fos controls retinal angiogenesis in OIR; Aim 2: To determine whether photoreceptor
c-Fos controls angiogenesis through modulating inflammatory signals; and Aim 3: To determine whether
pharmacological inhibitors of c-Fos suppress pathological retinal angiogenesis in OIR. The proposed research
is innovative because it represents a substantive departure from the status quo by identifying a photoreceptor-
initiated inflammatory signal to control pathological retinopathy in ROP. The proposed research is significant
because it will provide a novel ...

## Key facts

- **NIH application ID:** 10237902
- **Project number:** 5R01EY029238-03
- **Recipient organization:** BOSTON CHILDREN'S HOSPITAL
- **Principal Investigator:** YE SUN
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $429,225
- **Award type:** 5
- **Project period:** 2019-09-01 → 2024-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10237902

## Citation

> US National Institutes of Health, RePORTER application 10237902, Photoreceptor Determination of Retinal Blood Vessel Growth in Retinopathy (5R01EY029238-03). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10237902. Licensed CC0.

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