Prevalence estimates suggest that 23.6 million US residents have diabetes, and this number is predicted to double over the next thirty years. Diabetic retinopathy is the leading cause of blindness, and occurs in 100% of Type 1 and 60% of Type 2 diabetic patients within 20 years of diagnosis, and more than 12,000 patients become blind each year due to ocular complications from this disease. The underlying cause of diabetic retinopathy is damage to the retinal microvasculature from chronic hyperglycemia leading to increased vascular permeability and vascular occlusion. Recent evidence has shown that all of these events follow from the initial loss of pericytes on microvessels in the retina, which makes endothelial cells susceptible to diabetic conditions that result in the microaneurysms, venous changes, retinal capillary loss, and retinal ischemia. We propose to target the aberrant loss of pericytes by developing and evaluating a novel adult stem cell therapy that, we hypothesize, will supplement the native pericyte population and maintain microvessel homeostasis, thereby preventing the downstream effects that ultimately lead to macular edema. We have recently shown that a sub-population of adult human adipose-derived stem cells (hASCs) spontaneously differentiates into pericytes when injected in vivo, and in so doing, stabilizes the microvascular endothelium. We will test the hypothesis that cultured ASCs contain a sub-population of pericytes (or, pericyte precursors) that exhibits the intracellular signaling machinery, contractil properties, and functional abilities to diminish microvascular leakage, reduce capillary dropout, and prevent pathologic angiogenic induction and/or EC hyper-proliferation in three relevant murine models: oxygen-induced retinopathy (OIR), streptozocin induced diabetes (STZ), and Akimba whose pathological outcomes are related to early non-proliferative and late proliferative aspects of human DR. Our strategy is to supplement the endogenous pericyte population in order to enhance endothelial stability and prevent vessel loss. Therefore, we have designed three aims to evaluate the putative pericyte capacity of hASCs in the retina.
Aim 1 : Identify the hASC subpopulation(s) capable of becoming functional pericytes in vitro;
Aim 2 : Determine the capacity of hASCs to stabilize retinal vessels against acute (OIR) and chronic (STZ &Akimba) vascular insults;
Aim 3 : Determine the capacity of hASCs to enhance retinal revascularization and stabilize aberrant neovascularization following acute (OIR) and chronic (STZ &Akimba) vascular insults.

Public Health Relevance

Prevalence estimates suggest that 23.6 million US residents have diabetes, and this number is predicted to double over the next thirty years. Diabetic retinopathy is the leading cause of blindness, and occurs in 100% of Type 1 and 60% of Type 2 diabetic patients within 20 years of diagnosis. Current treatments are only able to treat the symptoms (not the cause) of the disease, are inefficient (require repeated application) and, over the long-term, ineffective (recurrent macular edema is a common outcome). We will develop and evaluate an adult stem cell based approach for treating diabetes that is aimed at supplementing and replacing diseased retinal perivascular cells with healthy adult progenitor cells, thereby preventing and mitigating the abnormal vascular responses that occur during diabetic retinopathy.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
1R01EY022063-01A1
Application #
8322941
Study Section
Special Emphasis Panel (ZRG1-CB-D (02))
Program Officer
Shen, Grace L
Project Start
2012-07-01
Project End
2016-06-30
Budget Start
2012-07-01
Budget End
2013-06-30
Support Year
1
Fiscal Year
2012
Total Cost
$516,372
Indirect Cost
$138,456
Name
University of Virginia
Department
Biomedical Engineering
Type
Schools of Medicine
DUNS #
065391526
City
Charlottesville
State
VA
Country
United States
Zip Code
22904
Walpole, Joseph; Mac Gabhann, Feilim; Peirce, Shayn M et al. (2017) Agent-based computational model of retinal angiogenesis simulates microvascular network morphology as a function of pericyte coverage. Microcirculation 24:
Seaman, Scott A; Cao, Yiqi; Campbell, Chris A et al. (2017) Arteriogenesis in murine adipose tissue is contingent on CD68+ /CD206+ macrophages. Microcirculation 24:
Keller 4th, T C Stevenson; Butcher, Joshua T; Broseghini-Filho, Gilson BrĂ¡s et al. (2016) Modulating Vascular Hemodynamics With an Alpha Globin Mimetic Peptide (Hb?X). Hypertension 68:1494-1503
Corliss, Bruce A; Azimi, Mohammad S; Munson, Jennifer M et al. (2016) Macrophages: An Inflammatory Link Between Angiogenesis and Lymphangiogenesis. Microcirculation 23:95-121
Seaman, Scott A; Tannan, Shruti C; Cao, Yiqi et al. (2016) Paradoxical Adipose Hyperplasia and Cellular Effects After Cryolipolysis: A Case Report. Aesthet Surg J 36:NP6-13
Zeiger, A S; Liu, F D; Durham, J T et al. (2016) Static mechanical strain induces capillary endothelial cell cycle re-entry and sprouting. Phys Biol 13:046006
Seaman, Scott A; Cao, Yiqi; Campbell, Chris A et al. (2016) Macrophage Recruitment and Polarization During Collateral Vessel Remodeling in Murine Adipose Tissue. Microcirculation 23:75-87
Cronk, Stephen M; Kelly-Goss, Molly R; Ray, H Clifton et al. (2015) Adipose-derived stem cells from diabetic mice show impaired vascular stabilization in a murine model of diabetic retinopathy. Stem Cells Transl Med 4:459-67
Seaman, Scott A; Tannan, Shruti Chudasama; Cao, Yiqi et al. (2015) Differential Effects of Processing Time and Duration of Collagenase Digestion on Human and Murine Fat Grafts. Plast Reconstr Surg 136:189e-199e
Durham, Jennifer T; Dulmovits, Brian M; Cronk, Stephen M et al. (2015) Pericyte chemomechanics and the angiogenic switch: insights into the pathogenesis of proliferative diabetic retinopathy? Invest Ophthalmol Vis Sci 56:3441-59

Showing the most recent 10 out of 18 publications