Neutrophils, traditionally viewed as first responders to infection or tissue damage, exhibit dynamic and diverse roles in ocular health and disease. This review elaborates on previous findings that showed how neutrophils contribute to ocular diseases. In ocular infections, neutrophils play a pivotal role in host defense by orchestrating inflammatory responses to combat pathogens. Furthermore, in optic nerve neuropathies and retinal degenerative diseases like age-related macular degeneration (AMD) and diabetic retinopathy (DR), neutrophils are implicated in neuroinflammation and tissue damage owing to their ability to undergo neutrophil extracellular trap formation (NETosis) and secretion of inflammatory molecules. Targeting neutrophil-dependent processes holds promise as a therapeutic strategy, offering potential avenues for intervention in ocular infections, cancers, and retinal degenerative diseases. Understanding the multifaceted roles of neutrophils in ocular diseases is crucial for developing targeted therapies to improve patient outcomes.

Age‐related macular degeneration (AMD), a leading cause of vision loss affecting retinal pigment epithelial (RPE) cells, remains largely unexplained by current genome‐wide association studies (GWAS) risk variants. Our research on Cryba1 , encoding βA3/A1‐crystallin protein, reveals its crucial role in RPE cell function via a novel epigenetic mechanism, also evident in human atrophic AMD samples. Loss of Cryba1 in mouse RPE cells triggers epigenetic changes by reducing histone deacetylase 3 (HDAC3) activity through two mechanisms. First, Cryba1 depletion reduces inositol polyphosphate multikinase (IPMK) expression, which potentially reduces inositol hexakisphosphate (InsP6) generation since IPMK's kinase activity is essential for producing InsP4 and InsP5 as precursors to InsP6. Since InsP4, InsP5, or InsP6 is crucial for HDAC3's interaction with the corepressor's DAD domains, reduced IPMK expression in Cryba1 ‐depleted cells likely diminishes the HDAC3‐DAD interaction, leading to a reduction in HDAC3's activity. Second, reduced βA3/A1 protein in Cryba1 ‐deficient cells impairs HDAC3's interaction with casein kinase 2 (CK2), resulting in decreased HDAC3 phosphorylation. Collectively, this increases H3K27 acetylation at the RET promoter region, likely enhancing the transcription of RET, a receptor tyrosine kinase critical for cell survival. Although RET is transcriptionally increased, Cryba1 loss disrupts its protein maturation, causing immature RET protein accumulation. This triggers age‐dependent endoplasmic reticulum (ER) stress, potentially contributing to the pathogenesis of AMD. Interestingly, although Cryba1 is not identified as an AMD‐linked variant in current GWAS, its loss may be linked to AMD mechanisms. These findings underscore the potential of gene‐agnostic and epigenetic therapeutic strategies for treating AMD.