Continual Discovery of Stem Cell Populations
A few years ago, uncovering another multipotent stem cell population would have been big news. That this one will pass by without much notice is a sign of progress. From ScienceDaily: scientists have "succeeded in finding and manipulating a population of cells that strongly resemble stem cells in the stomachs of mice. They have been able to show that these cells, which they call 'gastric progenitor cells,' can give rise to all the different types (or lineages) of specialized cells needed to form the functional stomach glands that line the lower portion of the stomach. ... The epithelial cells that make up the millions of glands of the stomach are constantly turning over. Most of the mature functioning cells live only 20 to 60 days before being replaced by progeny of dividing resident stem cells. These stem cells are not only a constant source of new cells, but they represent an important reservoir for repair of damage to the stomach caused by injury or inflammation. In addition, since the stem cells are the longest-lived of the gastric cells, it is thought that these are the only cells that live long enough to accumulate the multiple mutations that can cause cancers. For these reasons, the ability to identify and manipulate stomach progenitor cells has been an important goal for decades."
Link: http://www.sciencedaily.com/releases/2007/10/071003171925.htm