Biomarker of Diabetic Retinopathy

Study Overview
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Brief Summary
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Diabetic retinopathy (DR) is a complication of diabetes in which blood vessels supplying blood to the back of the eye (retina) are dysfunctional. This can lead to an improper supply of oxygen and nutrients to the retinal tissue, or it may trigger the formation of new blood vessels in response to the oxygen/nutrient deficiency. Ultimately affecting the normal vision. There is no known marker that will provide information on the health status of retinal blood vessels. Using highly specialized cells in the blood, this study will try to discover a marker of DR.

Official Title
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Biomarker of Diabetic Retinopathy

Conditions
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Diabetic Retinopathy

Intervention / Treatment
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* Other: Blood draw


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ability to cooperate with imaging procedures. Health status: established type 2 diabetes No history of panretinal photocoagulation (PRP) No history of treatment with intravitreal agents for past 12 months Exclusion Criteria: Previous or current malignancy Acute or chronic infection (HIV, hepatitis B or C, tuberculosis) Cerebral vascular accident or cerebral vascular procedure Current pregnancy History of organ transplantation Presence of a graft (to avoid any effect of the graft) History of previous vitrectomy Subjects with a history of age-related macular degeneration age-related macular degeneration (AMD), glaucoma, uveitis, and branched or central vein occlusion.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Healthy Control<br> | Other: Blood draw<br>* Blood samples will be collected via venipuncture<br>|
| Diabetes but no retinopathy<br> | Other: Blood draw<br>* Blood samples will be collected via venipuncture<br>|
| Mild non proliferative diabetic retinopathy<br> | Other: Blood draw<br>* Blood samples will be collected via venipuncture<br>|
| Moderate non proliferative diabetic retinopathy<br> | Other: Blood draw<br>* Blood samples will be collected via venipuncture<br>|
| Severe non proliferative diabetic retinopathy<br> | Other: Blood draw<br>* Blood samples will be collected via venipuncture<br>|
| Proliferative diabetic retinopathy<br> | Other: Blood draw<br>* Blood samples will be collected via venipuncture<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| mRNA and miRNA sequencing of circulating angiogenic cells isolated from study participants |  | Baseline and change in RNA signature in follow up visit (between 3-5 years) | 
| Surface marker expression of inflammatory markers using flow cytometry |  | Baseline | 
| miRNA expression |  | Baseline | 
| Epigenetic changes in circulating angiogenic cells with different severities of diabetic retinopathy |  | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Early Treatment Diabetic Retinopathy Study (ETDRS) clinical scoring in wide-field fundus photography | The scoring will be between 10 (no retinopathy) and 85 (advanced proliferative diabetic retinopathy). Higher score means worst outcome | Baseline and follow up visit (between 3-5 years) | 
| Presence or absence of neovascularization and total area of non-perfusion in fluorescein angiography (FA) |  | Baseline and follow up visit (between 3-5 years) | 
| Change in vessel density in optical coherence tomography angiography (OCT-A) |  | Baseline and follow up visit (between 3-5 years) | 
| Change in retinal thickness in optical coherence tomography angiography (OCT-A) |  | Baseline and follow up visit (between 3-5 years) |