Small populations of stem cells sustain the limbal-corneal and the conjunctival lineages. In the limbal-corneal system, where stem cells localize preferentially to the limbus, total or zonal damage produces epithelial limbal stem cell deficiency syndromes. In recent years, a variety of surgical stem cell transplant methodologies have been applied to reestablish the limbal stem cell niche for vision restoration. The long term goals of our studies are a) understand the functional nature of ocular surface stem cells, in particular those of the limbus;and b) apply this critical knowledge for the optimization of ex vivo limbal cell population expansion to improve surface reconstructive procedures based on transplantation of stem cell-rich cell populations. During the initial funding period of this grant we characterized small stem cell cohorts known as side populations (SPs) from both conjunctival and limbal epithelia. Our studies showed that these cells derive from cells that have been in the slow cycling state in vivo and to display several other features recognized for stem cells in vitro. Based on finding during this period we now propose, in Specific Aim1 to test the hypothesis that cell cohorts expressing CD62E or excluding mitotrakcker deep red constitute additional component of an heterogeneous stem/precursor limbal and conjunctival epithelial cell population and in Specific Aim2 to test the hypothesis that observed overexpressions of several genes capable of affecting gene transcription globally and usually referred as master or cell fate genes (PAX6, MEIS1, SIX1, MSX1, HES1 ID1, the MXD1/MAX system controlling MYC activity) contribute to cell stemness in the limbal epithelium. The knowledge acquired in the comparative characterization of the cell cohorts associated with the stem/precursor cell compartment in Aim 1, combined with the identification of gene expressions and signal pathways that are associated with preservation or loss of the stem/precursor cell state in Specific Aim 2, will provide the cogent basis to improve strategies for either maximization of stem/precursor cell yields during limbal cells expansion in vitro, or alternatively, facilitate stem cell rescue from generic proliferative (basal) epithelial cells through reversion of phenotype for the benefit of reconstructive ocular surface procedures.
Specific aim 3 seeks to apply the knowledge and expertise acquired in the two previous specific aims for the genetic and/pharmacological manipulation of freshly isolated limbal epithelial cells to attain effective expansion of these cells while maintaining their capacity for corneal epithelial function recovery in vivo.

Public Health Relevance

Damage to the limbus by chemical or thermal injuries, microbial infection, or autoimmune reactions result in limbal stem cell deficiencies (LSCD) causing visual loss and blindness. Transplants with expanded limbal cell populations incorporating stem cells can restore or improve vision. We now propose a roadmap to test the impact of genes identified in these stem cells on their phenotype and survival and to apply the gained insight to increase the content of stem cells in expanded limbal populations and thereby improve the outcome of corneal reconstruction surgeries.

National Institute of Health (NIH)
National Eye Institute (NEI)
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Anterior Eye Disease Study Section (AED)
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Mckie, George Ann
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Icahn School of Medicine at Mount Sinai
Schools of Medicine
New York
United States
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Wolosin, J Mario; Ritch, Robert; Bernstein, Audrey M (2018) Is Autophagy Dysfunction a Key to Exfoliation Glaucoma? J Glaucoma 27:197-201
Bernstein, Audrey M; Ritch, Robert; Wolosin, Jose M (2018) Exfoliation Syndrome: A Disease of Autophagy and LOXL1 Proteopathy. J Glaucoma 27 Suppl 1:S44-S53
Lee, Hyun Jung; Wolosin, J Mario; Chung, So-Hyang (2017) Divergent effects of Wnt/?-catenin signaling modifiers on the preservation of human limbal epithelial progenitors according to culture condition. Sci Rep 7:15241
Wolosin, J Mario; Zamudio, Aldo; Wang, Zheng (2017) Application of JC1 for non-toxic isolation of cells with MDR transporter activity by flow cytometry. PLoS One 12:e0174905
Selver, Ozlem Barut; Durak, Ismet; G├╝rdal, Mehmet et al. (2016) Corneal recovery in a rabbit limbal stem cell deficiency model by autologous grafts of tertiary outgrowths from cultivated limbal biopsy explants. Mol Vis 22:138-49
Zamudio, Aldo; Wang, Zheng; Chung, So-Hyang et al. (2016) Inhibition of TGF? cell signaling for limbal explant culture in serumless, defined xeno-free conditions. Exp Eye Res 145:48-57
Want, Andrew; Gillespie, Stephanie R; Wang, Zheng et al. (2016) Autophagy and Mitochondrial Dysfunction in Tenon Fibroblasts from Exfoliation Glaucoma Patients. PLoS One 11:e0157404
Yang, Yuanquan; Wang, Zheng; Yang, Hua et al. (2013) TRPV1 potentiates TGF?-induction of corneal myofibroblast development through an oxidative stress-mediated p38-SMAD2 signaling loop. PLoS One 8:e77300
Jeon, Sohee; Choi, Seong Hyun; Wolosin, J Mario et al. (2013) Regeneration of the corneal epithelium with conjunctival epithelial equivalents generated in serum- and feeder-cell-free media. Mol Vis 19:2542-50
Yang, Yuanquan; Yang, Hua; Wang, Zheng et al. (2013) Functional TRPV1 expression in human corneal fibroblasts. Exp Eye Res 107:121-9

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