The finding, to appear in the journal Science and reported online in the Dec. 12 issue of Science Express, offers promise for what could be the first broadly adaptable way to find such master cells, which can create tissue as needed and are seen as the foundation for regenerative medicine. Before this finding, the only stem cells that had been isolated and characterized were from blood, nerve cells and embryonic tissue.
In order to avoid accumulating damaging mutations, long-lived stem cells in their natural home (niche) are often "slow cycling," dividing only infrequently. However, upon injury or normal "wear and tear," stem cells are mobilized to leave their niche, divide and replenish the damaged tissue. The study provides a list of more than 150 genetic factors that distinguish the long-lived, "slow cycling" stem cells of the skin from their short-lived, rapidly dividing "daughter cells."
This information will help scientists understand how these mysterious cells are able to replenish both skin epidermis and hair, and what nutrients may help stem cells produce more stem cells in the laboratory. In addition, some of these new genes are likely to serve as markers for these stem cells, making them easier to identify and isolate in the future.
"We now have a much better picture of the traits of mouse skin stem cells, and we can now use these genetic data to examine whether human skin stem cells possess similar traits to the mouse stem cells," says the study's lead investigator, Elaine Fuchs, Ph.D., professor and head of the Laboratory of Mammalian C
Contact: Joseph Bonner