And some positive news.
Skin Cells Can Turn Into Brain, Nerve Cells, Scientists Say
By Angela Zimm
Cambridge, Massachusetts, Aug. 13 (Bloomberg) -- Stem cells derived from skin may be more versatile than scientists have believed, capable of taking on functions that may repair damaged nerves, brain and other tissues, researchers said.
In the September issue of Nature Cell Biology, scientists at McGill University in Montreal produced stem cells from the skin of mice that can differentiate into nerve, muscle, brain and fat cells. In a smaller experiment, researchers isolated similar cells from adult human skin that can turn into nerve cells.
Scientists hope that stem cells, which can adapt to many functions, have the potential to cure disease and mend injuries. Adult stem cells, though, were thought to be limited to taking on functions of their tissue of origin. The findings are significant because stem cells extracted from adult skin appear to share some properties as pliable cells from embryos, researchers said.
"Adult stem cells, so far, really don't proliferate particularly well," said Freda Miller, professor of neurology and neurosurgery at McGill University and an author of the study. "These (skin-derived) cells more easily make up their minds to go one way or other and seem to be more promiscuous, in a sense."
Embryonic stem cells are unique because they can become any cell in the body, giving them potential in treating a wide range of diseases such as diabetes or Parkinson's. The harvesting of those cells in human research, though, has become divisive, since it requires the destruction of an embryo.
Advantages
The discovery that skin stem cells are "multipotent" -- meaning they're capable of becoming other types of cells -- raises the possibility of therapeutic approaches that may even offer some advantages over embryonic cells.
For example, a patient's own skin tissue could be used to extract stem cells that can be cultured into replacement cells and transplanted to an injury with less risk of rejection, Miller said. Skin, the body's largest organ, also is easier to access than brain or nerve tissue.
"People have been realizing that throughout the body there may be stem cells with many of the same mechanisms in growth and development throughout adult life that play a role in normal repair and regeneration," said Dr. Doros Platika, chief executive of Cambridge, Massachusetts-based Curis Inc., which funded the study.
Aegera Therapeutics Inc., a closely held biotechnology company based in Montreal, is collaborating with Curis in the research.
In the larger study, scientists isolated mouse stem cells from the dermis, or inner layer of skin, and treated them with a solution of growth-factor proteins. After isolating neural cells, scientists found they could also culture cells for brain, muscle and fat tissue.
Researchers are now testing skin-derived cells in animals to see if they grow outside a petri dish or have a therapeutic effect.
"This is a classic case of just looking under the light bulb," Miller said. "Just by simplistic manipulation we were able to direct the cells preferentially one way or another."
quote.bloomberg.com |
