- The Washington Times - Tuesday, August 14, 2001

For the first time, researchers have captured from the skin of adult mice and humans stem cells capable of growing into brain cells and a range of other tissues.
The feat offers new hope for treating neurological disorders, and comfort to President Bush, who last week set strict limits on publicly funded U.S. research using stem cells derived from human embryos, which are destroyed when the powerful cells are extracted.
The new research, published Monday in Nature Cell Biology, bolsters the view that scientists can find alternative — and less controversial sources of stem cells, which have the unique power to divide indefinitely before growing into the various tissues and parts that constitute any living being.
The stem cells harvested at McGill University's Montreal Neurological Institute have grown into smooth muscle cells, fat cells and brain cells — including neurons, the individual thinking units of the human mind, and glial cells, which, among other things, produce the fatty white sheaths around nerve fibers in the brain that speed signals between neurons.
"They are beautiful neurons," said molecular biologist and co-author Freda Miller. "You kind of look at them and say, 'This can't be true.' But then you go back and do it 10 times, and you realize it is true."
While no one yet knows if these neurons can transmit electrical and chemical signals as they do in the brain, one intriguing aspect of growing them from stem cells found in skin is that scientists could have a vast and easily accessible supply.
Dr. Ronald Worton, CEO and scientific director of the Ottawa Health Research Institute and head of Canada's Stem Cell Network, said stem cells that can produce brain cells have been found in the brain itself, but this is the first time they have been grown from stem cells found in skin.
"Two years ago, I would have said this is a big surprise, and I wouldn't have believed it unless it could be widely reproduced," Dr. Worton said. "But then the dogma used to be that if you were a stem cell in [adult] bone marrow, you could only make blood cells, or if you were a stem cell in skin, you only make skin. There's now enough lab work to say the dogma was wrong."
Scientists hope to one day chemically goad stem cells into becoming replacement tissues for ailing patients, such as insulin-producing cells for diabetics, brain cells that pump out dopamine for Parkinson's sufferers, or cells rich in dystrophin for people with muscular dystrophy.
Patients receiving new tissue grown from stem cells taken from their own skin would face far fewer problems of rejection, if any, than they would after receiving a transplant of stem cells derived from human embryos.
Miss Miller and Jean Toma, the paper's lead author, thought several years ago that because skin, like blood, regenerates itself on a rapid and regular basis, it could be a rich source of stem cells.
In particular, they wondered about cells beneath the epidermis in the skin's second layer, the dermis. That layer contains nerve cells that relay sensations such as touch to the brain. Since these cells regenerate after injuries such as burns or gashes, the Montreal group looked for the precursors of these sensory cells, hoping to find the stem cells that produce them.
They isolated them first in the nasal passages of mice. But the source was not practical, given the difficulty of extracting enough from a tiny, damp airway. Then they tested their hypothesis with skin from mice and from a human scalp.
c Distributed by Scripps Howard News Service.

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