NEW YORK (Reuters Health) - Stem cells in the hair follicle bulge can generate all epithelial cell types within the intact follicle, a US research team reports. They propose that “the hair follicle stem cell genes could provide targets for the treatment of hair loss and other disorders of the cutaneous epithelium.”
As described in the advance issue of Nature Biotechnology, published online March 14, Dr. George Cotsarelis, at the University of Pennsylvania in Philadelphia, and his associates used a keratin gene promoter to label the bulge stem cells of transgenic mice with the lacZ gene.
The team then and forced the animals’ hair follicles into anagen growth phase, and tracked the fate of the labeled bulge cells. Multipotency was demonstrated when all epithelial cell types that grew in the lower hair follicle and hair shaft expressed lacZ.
Moreover, gene expression profiling of these stem cells revealed multiple receptor and signaling pathways, many previously unknown, the researchers report.
Compared with non-bulge basal keratinocytes, 157 genes were differentially expressed in hair follicle stem cells. Of the 97 genes that were upregulated, 34 were common to those observed in hematopoietic stem cells, while 20 and 22 have been identified in neural stem cells and in embryonic stem cells, respectively.
“Upregulation of three genes... was common to all four cell types, suggesting that these genes may serve a common function in maintaining the stem cell state,” Dr. Cotsarelis’ group adds.
They believe their findings will lead to “rapid advances in our understanding of the role of epithelial stem cells in alopecia, wounding, aging and carcinogenesis.”
Source: Nat Biotechnol 2004. [ Google search on this article ]
MeSH Headings:Biological Sciences: Biology: Gene Expression Regulation: Genetics: Genetics, Biochemical: Molecular Biology: Biological SciencesCopyright © 2002 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.