Assessment of the Ocular Microbiome in Health and Disease

The microbiome is defined as a community of microbial organisms that reside in a specific host niche. There is a growing body of literature on the association between gut microbiome and disease entities such as inflammatory bowel disease, colon cancer and presumably an association that might influence response to treatment in some patients.

Recent data suggest the existence of a resident ocular microbiota that may play a protective role in corneal infections [1-4]. However, not much is known about the ocular microbiome and its association with disease or response to treatment. The National Eye Institute (NEI) recently hosted a symposium to discuss challenges to characterize the ocular microbiome and its role in promoting or preventing ocular diseases. One of the major challenges discussed is the lack of a normative population- based database describing the ocular microbiome.

In response the NEI as part of the Anterior segment initiative put out an RFA requesting proposals on methods of collection of biological samples and associated clinical data (e.g. demographic, residence, medications, allergies); processing of samples to extract analytes (e.g., DNA, RNA, protein, metabolites) and characterizing microorganisms in a low biomass niche, specifically the ocular surface using16S rRNA marker gene, whole metagenome sequencing (WMS), and metatranscriptomics approaches.

Inclusion criteria

We will include subjects who meet all of the following criteria:

• 18 years of age or older
• Provide informed consent
• Cohort A - normal eyes with no ocular disease
• Cohort B - primary open angle glaucoma/Ocular hypertension defined as mild glaucoma which is well controlled with no more than one drop of prostaglandin use daily for the past 6 months
• Cohort C - non-infectious keratopathy not using any prescription medication (OTC artificial tears are acceptable)
• Cohort D - Dry AMD (age related macular degeneration)
• Cohort E - Wet AMD
• Cohort F - diabetic retinopathy

Exclusion criteria

We will exclude subjects who meet all of the following criteria:

• Prior ocular disease either of the anterior or posterior segment
• Any medical comorbidities except well controlled DH and HTN
• Unable to follow up with study procedures as described