Under normal circumstances the endothelium of retinal capillaries divide infrequently. This fact suggests that there is a very powerful mechanism which controls growth at the microvascular level. Although the exact nature of this mechanism is not known, it is likely that a number of factors contribute to vascular growth control. Clinical and experimental observations have implicated the following four factors in the regulation of capillary growth: capillary integrity, cell-cell interactions, the nutrient supply (oxygen) and the extracellular matrix. Because of the inaccessibility of the capillary it is difficult to investigate these factors in vivo. However, using cultures of microvascular endothelial cells (EC) and pericytes the contribution of each of these variables to the control process can be investigated. Specifically, this application proposes the following: (1) To characterize pericyte function with particular emphasis on contractile potential using affinity-purified antibodies to contractile proteins, time-lapse video microscopy and computer-assisted quantitation. (2) To investigate the interactions between capillary EC and pericytes with respect to their influence on capillary growth using conditioned media and co-cultures studies. (3) To elucidate the differential effects of oxygen on capillary EC and pericytes and to investigate the mechanism of oxygen damage to EC. The cells will be grown under altered oxygen concentrations and examined for changes in enzymes involved in protection against oxygen by-products. The effect of vessel source and age and cell density on sensitivity to oxygen will be assessed. Finally, the effect of oxygen exposure on the ability of the cells to migrate will be investigated using migration assays and specific cytoskeletal probes. (4) To investigate the interactions of pericytes and EC with basement membrane-associated glycosaminoglycans by quantitating and characterizing the specific binding of hyaluronic acid and heparin-like glycosaminoglycans to EC and pericytes in vitro. The ultimate goal of these studies is to identify and characterize the individual factors which contribute to microvascular growth control. By providing specific information on the role of microvascular cells, the results of these studies will add to our understanding of the multiple factors which play a role in retinal neovascularization.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
5R01EY005318-05
Application #
3260344
Study Section
Visual Sciences A Study Section (VISA)
Project Start
1983-07-01
Project End
1991-06-30
Budget Start
1987-07-01
Budget End
1988-06-30
Support Year
5
Fiscal Year
1987
Total Cost
Indirect Cost
Name
Children's Hospital Boston
Department
Type
DUNS #
076593722
City
Boston
State
MA
Country
United States
Zip Code
02115
Pearsall, Elizabeth A; Cheng, Rui; Zhou, Kelu et al. (2017) PPAR? is essential for retinal lipid metabolism and neuronal survival. BMC Biol 15:113
Machuca-Parra, Arturo I; Bigger-Allen, Alexander A; Sanchez, Angie V et al. (2017) Therapeutic antibody targeting of Notch3 signaling prevents mural cell loss in CADASIL. J Exp Med 214:2271-2282
Lam, Jonathan D; Oh, Daniel J; Wong, Lindsay L et al. (2017) Identification of RUNX1 as a Mediator of Aberrant Retinal Angiogenesis. Diabetes 66:1950-1956
Zahr, Alisar; Alcaide, Pilar; Yang, Jinling et al. (2016) Endomucin prevents leukocyte-endothelial cell adhesion and has a critical role under resting and inflammatory conditions. Nat Commun 7:10363
Sánchez-Palencia, Diana M; Bigger-Allen, Alex; Saint-Geniez, Magali et al. (2016) Coculture Assays for Endothelial Cells-Mural Cells Interactions. Methods Mol Biol 1464:35-47
Wong, Lindsay L; Lee, Nahyoung Grace; Amarnani, Dhanesh et al. (2016) Orbital Angiogenesis and Lymphangiogenesis in Thyroid Eye Disease: An Analysis of Vascular Growth Factors with Clinical Correlation. Ophthalmology 123:2028-36
Primo, Vincent; Graham, Mark; Bigger-Allen, Alexander A et al. (2016) Blood biomarkers in a mouse model of CADASIL. Brain Res 1644:118-26
Arboleda-Velasquez, Joseph F; Valdez, Cammi N; Marko, Christina K et al. (2015) From pathobiology to the targeting of pericytes for the treatment of diabetic retinopathy. Curr Diab Rep 15:573
Kim, Leo A; Wong, Lindsay L; Amarnani, Dhanesh S et al. (2015) Characterization of cells from patient-derived fibrovascular membranes in proliferative diabetic retinopathy. Mol Vis 21:673-87
Arboleda-Velasquez, Joseph F; Primo, Vincent; Graham, Mark et al. (2014) Notch signaling functions in retinal pericyte survival. Invest Ophthalmol Vis Sci 55:5191-9

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