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Publications (2)11.72 Total impact

  • Article: Circulating Mononuclear Progenitor Cells: Differential Roles for Sub-populations in Repair of Retinal Vascular Injury.
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    ABSTRACT: PURPOSE: We examined effect on retinal vascular homing of exogenous CD34+ and CD14+ progenitor cells using mouse models of chronic (streptozotocin-induced [STZ] diabetes) and acute (ischemia/reperfusion [I/R]) ocular vascular injury. METHODS: STZ-treated mice of short or long duration (≤4, ≥11 months) diabetes, along with age- and gender-matched controls, were given alone or in combination intravitreous injections of human CD34+ and CD14+ cells isolated from healthy or diabetic donors. I/R injured mice were given diabetic or non-diabetic CD34+ cells with mesenchymal stem cells (MSCs), or diabetic CD34+ cells manipulated by ex vivo fucosylation with ASC-101. Injected cells were localized by fluorescent immunocytochemistry and degree of retinal vascular co-localization quantified morphometrically. Permeability was assessed by fluorescent albumin leakage. RESULTS: Diabetic CD14+ cells associated with vessels to a greater degree than diabetic CD34+ cells. Vascular permeability was reduced only by nondiabetic cells, and only at the highest number of cells tested. Diabetic CD34+ cells consistently demonstrated reduced migration. There was 2-fold and 4-fold increase over control in the specific localization of diabetic CD34+ cells within the vasculature when these cells were co-administered with MSCs or ex vivo fucosylated prior to injection, respectively. CONCLUSIONS: Diabetic CD14+ cells, unlike diabetic CD34+ cells, retain robust homing characteristics. CD34+ or CD14+ subsets rather than whole bone marrow or peripheral blood cells may prove more beneficial in autologous cell therapy for diabetics. Co-administration with MSCs, or ex vivo fucosylation, may enhance utility of CD34+ cells in cell therapy for diabetic ocular conditions like macular ischemia and retinal nonperfusion.
    Investigative ophthalmology & visual science 04/2013; · 3.43 Impact Factor
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    Article: Ischemic vascular damage can be repaired by healthy, but not diabetic, endothelial progenitor cells.
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    ABSTRACT: Endothelial precursor cells (EPCs) play a key role in vascular repair and maintenance, and their function is impeded in diabetes. We previously demonstrated that EPCs isolated from diabetic patients have a profound inability to migrate in vitro. We asked whether EPCs from normal individuals are better able to repopulate degenerate (acellular) retinal capillaries in chronic (diabetes) and acute (ischemia/reperfusion [I/R] injury and neonatal oxygen-induced retinopathy [OIR]) animal models of ocular vascular damage. Streptozotocin-induced diabetic mice, spontaneously diabetic BBZDR/Wor rats, adult mice with I/R injury, or neonatal mice with OIR were injected within the vitreous or the systemic circulation with fluorescently labeled CD34(+) cells from either diabetic patients or age- and sex-matched healthy control subjects. At specific times after administering the cells, the degree of vascular repair of the acellular capillaries was evaluated immunohistologically and quantitated. In all four models, healthy human (hu)CD34(+) cells attached and assimilated into vasculature, whereas cells from diabetic donors uniformly were unable to integrate into damaged vasculature. These studies demonstrate that healthy huCD34(+) cells can effectively repair injured retina and that there is defective repair of vasculature in patients with diabetes. Defective EPCs may be amenable to pharmacological manipulation and restoration of the cells' natural robust reparative function.
    Diabetes 04/2007; 56(4):960-7. · 8.29 Impact Factor