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Title: Neural stem cells in the adult ciliary epithelium express GFAP and are regulated by Wnt signaling

Abstract

The identification of neural stem cells with retinal potential in the ciliary epithelium (CE) of the adult mammals is of considerable interest because of their potential for replacing or rescuing degenerating retinal neurons in disease or injury. The evaluation of such a potential requires characterization of these cells with regard to their phenotypic properties, potential, and regulatory mechanisms. Here, we demonstrate that rat CE stem cells/progenitors in neurosphere culture display astrocytic nature in terms of expressing glial intermediate neurofilament protein, GFAP. The GFAP-expressing CE stem cells/progenitors form neurospheres in proliferating conditions and generate neurons when shifted to differentiating conditions. These cells express components of the canonical Wnt pathway and its activation promotes their proliferation. Furthermore, we demonstrate that the activation of the canonical Wnt pathway influences neuronal differentiation of CE stem cells/progenitors in a context dependent manner. Our observations suggest that CE stem cells/progenitors share phenotypic properties and regulatory mechanism(s) with neural stem cells elsewhere in the adult CNS.

Authors:
 [1];  [1];  [1];  [2];  [2];  [3]
  1. Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68198-5840 (United States)
  2. Eppley Institute for Cancer Research, University of Nebraska Medical Center, Omaha, NE 68198-6805 (United States)
  3. Department of Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68198-5840 (United States). E-mail: iahmad@unmc.edu
Publication Date:
OSTI Identifier:
20798750
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 339; Journal Issue: 2; Other Information: DOI: 10.1016/j.bbrc.2005.11.064; PII: S0006-291X(05)02572-6; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; EPITHELIUM; EVALUATION; INJURIES; NERVE CELLS; PROTEINS; RATS; RETINA; STEM CELLS

Citation Formats

Das, Ani V., Zhao Xing, James, Jackson, Kim, Min, Cowan, Kenneth H., and Ahmad, Iqbal. Neural stem cells in the adult ciliary epithelium express GFAP and are regulated by Wnt signaling. United States: N. p., 2006. Web. doi:10.1016/j.bbrc.2005.11.064.
Das, Ani V., Zhao Xing, James, Jackson, Kim, Min, Cowan, Kenneth H., & Ahmad, Iqbal. Neural stem cells in the adult ciliary epithelium express GFAP and are regulated by Wnt signaling. United States. doi:10.1016/j.bbrc.2005.11.064.
Das, Ani V., Zhao Xing, James, Jackson, Kim, Min, Cowan, Kenneth H., and Ahmad, Iqbal. Fri . "Neural stem cells in the adult ciliary epithelium express GFAP and are regulated by Wnt signaling". United States. doi:10.1016/j.bbrc.2005.11.064.
@article{osti_20798750,
title = {Neural stem cells in the adult ciliary epithelium express GFAP and are regulated by Wnt signaling},
author = {Das, Ani V. and Zhao Xing and James, Jackson and Kim, Min and Cowan, Kenneth H. and Ahmad, Iqbal},
abstractNote = {The identification of neural stem cells with retinal potential in the ciliary epithelium (CE) of the adult mammals is of considerable interest because of their potential for replacing or rescuing degenerating retinal neurons in disease or injury. The evaluation of such a potential requires characterization of these cells with regard to their phenotypic properties, potential, and regulatory mechanisms. Here, we demonstrate that rat CE stem cells/progenitors in neurosphere culture display astrocytic nature in terms of expressing glial intermediate neurofilament protein, GFAP. The GFAP-expressing CE stem cells/progenitors form neurospheres in proliferating conditions and generate neurons when shifted to differentiating conditions. These cells express components of the canonical Wnt pathway and its activation promotes their proliferation. Furthermore, we demonstrate that the activation of the canonical Wnt pathway influences neuronal differentiation of CE stem cells/progenitors in a context dependent manner. Our observations suggest that CE stem cells/progenitors share phenotypic properties and regulatory mechanism(s) with neural stem cells elsewhere in the adult CNS.},
doi = {10.1016/j.bbrc.2005.11.064},
journal = {Biochemical and Biophysical Research Communications},
number = 2,
volume = 339,
place = {United States},
year = {Fri Jan 13 00:00:00 EST 2006},
month = {Fri Jan 13 00:00:00 EST 2006}
}
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