The long term goal of this project is to use molecular approaches to define a set of cell specific surface narkers for human as well as rodent limbal stem cells and to use those markers as tools to characterize stem cells for the corneal epithelium in humans, rats, and mice in health and disease. Clinical experience and practice has shown us that limbal stem cells serve as the source for the cells comprising the corneal epithelium. At present, experimental confirmation that cells in the limbus are stem cells relies upon data from studies of vitro cell proliferation capacity and on the identification of a subset of these cells as slow-cycling. We hypothesize that a specific repertoire of cell surface markers exists which can define and select stem cells within the corneal limbus. Identification of such markers will aid in the study of the human ocular surface by providing tools to use to both select for and to target specific drugs or genes to these cells. Further, they will provide tools to allow for the analysis of limbal stem cell properties both in vivo and in vitro.
The specific aims of this application are: 1) Identification of corneal stem-like cells from donor human corneas by selection based on cell adhesion properties, integrin expression profiles, and the ability of cells to proliferate in vitro, 2. Using phage displayed peptide libraries, identification of peptides that bind specifically to human, mouse, and rat limbal basal cells and use of those peptides to isolate and characterize stem cell specific surface markers, 3. In the mouse and rat, determine whether the slow-cycling cells observed in the limbus after neonatal BrdU administration possess similar cell surface markers as do human corneal stem cells, and 4. Using the knowledge and tools developed in Aims 1-3, characterize the limbal stem cells in the mouse under conditions where their differentiation and/or proliferation is altered in wild-type and in genetically engineered mice exhibiting symptoms of stem cell disease. Discovering specific molecular markers for the limbal stem cells will aid in the development of treatments for stem cell deficiency diseases of the ocular surface in humans.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
1R01EY013559-01
Application #
6360365
Study Section
Visual Sciences A Study Section (VISA)
Program Officer
Fisher, Richard S
Project Start
2001-09-01
Project End
2006-08-31
Budget Start
2001-09-01
Budget End
2002-08-31
Support Year
1
Fiscal Year
2001
Total Cost
$323,800
Indirect Cost
Name
George Washington University
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
City
Washington
State
DC
Country
United States
Zip Code
20052
Pal-Ghosh, Sonali; Pajoohesh-Ganji, Ahdeah; Tadvalkar, Gauri et al. (2016) Topical Mitomycin-C enhances subbasal nerve regeneration and reduces erosion frequency in the debridement wounded mouse cornea. Exp Eye Res 146:361-9
Pajoohesh-Ganji, Ahdeah; Pal-Ghosh, Sonali; Tadvalkar, Gauri et al. (2015) Partial denervation of sub-basal axons persists following debridement wounds to the mouse cornea. Lab Invest 95:1305-18
Pajoohesh-Ganji, Ahdeah; Pal-Ghosh, Sonali; Tadvalkar, Gauri et al. (2012) Corneal goblet cells and their niche: implications for corneal stem cell deficiency. Stem Cells 30:2032-43
Stepp, Mary Ann; Pal-Ghosh, Sonali; Tadvalkar, Gauri et al. (2010) Loss of syndecan-1 is associated with malignant conversion in skin carcinogenesis. Mol Carcinog 49:363-73
Pal-Ghosh, Sonali; Tadvalkar, Gauri; Jurjus, Rosalyn A et al. (2008) BALB/c and C57BL6 mouse strains vary in their ability to heal corneal epithelial debridement wounds. Exp Eye Res 87:478-86
Jurjus, Rosalyn A; Liu, Yueyuan; Pal-Ghosh, Sonali et al. (2008) Primary dermal fibroblasts derived from sdc-1 deficient mice migrate faster and have altered alphav integrin function. Wound Repair Regen 16:649-60
Stepp, Mary Ann; Liu, Yueyuan; Pal-Ghosh, Sonali et al. (2007) Reduced migration, altered matrix and enhanced TGFbeta1 signaling are signatures of mouse keratinocytes lacking Sdc1. J Cell Sci 120:2851-63
Pajoohesh-Ganji, Ahdeah; Pal-Ghosh, Sonali; Simmens, Samuel J et al. (2006) Integrins in slow-cycling corneal epithelial cells at the limbus in the mouse. Stem Cells 24:1075-86
Pajoohesh-Ganji, Ahdeah; Stepp, Mary Ann (2005) In search of markers for the stem cells of the corneal epithelium. Biol Cell 97:265-76
Hutcheon, Audrey E K; Guo, Xiaoqing Q; Stepp, Mary Ann et al. (2005) Effect of wound type on Smad 2 and 4 translocation. Invest Ophthalmol Vis Sci 46:2362-8

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