Retinol-binding protein 3 in ophthalmology: current evidence, research progress, and future perspectives

Area of Science:

• Ophthalmology
• Retinal Biology
• Molecular Medicine

Background:

• Retinol-binding protein 3 (RBP3) is a key glycoprotein in retinoid transport between photoreceptors and the retinal pigment epithelium.
• Emerging evidence indicates RBP3's involvement in retinal metabolic regulation, neuroprotection, and immune responses.
• RBP3's role extends beyond the visual cycle, suggesting broader implications in retinal health and disease.

Purpose of the Study:

• To review and critically assess the current evidence on RBP3's role in various retinal diseases.
• To evaluate RBP3 as a potential biomarker and therapeutic candidate for these conditions.
• To identify knowledge gaps and suggest future research directions for RBP3.

Main Methods:

• Literature review and critical summary of existing studies on RBP3.
• Analysis of evidence from clinical association studies, proteomic analyses, and preclinical models.
• Focus on RBP3's involvement in diabetic retinopathy, retinal degeneration, pathological myopia, primary congenital glaucoma, and uveitis.

Main Results:

• Diabetic retinopathy shows the most extensive evidence for RBP3 involvement, with correlational clinical data and preclinical findings.
• Evidence for RBP3 in primary congenital glaucoma and uveitis is more limited, primarily from proteomics and animal models.
• RBP3 is considered a promising but not fully validated biomarker and therapeutic candidate.

Conclusions:

• RBP3 plays a significant role in retinoid trafficking and potentially in various retinal diseases.
• Further large-scale prospective and mechanistic studies are needed to validate RBP3's clinical utility and therapeutic potential.
• Clarifying disease-stage-specific roles and receptor-mediated mechanisms is crucial for future RBP3-based strategies.