http://www.nationalmssociety.org/articles.asp?SMContentIndex=0&SMContentSet=0

August 16, 2001
Agence France-Presse

SYDNEY, Aug 16 (AFP) - Australian scientists said Thursday they may have discovered a way to successfully treat brain, nerve and spinal injuries by harvesting adult neural stem cells.

Conditions such as Parkinson's and Alzheimer's could also be reversed after researchers at the prestigious Walter and Eliza Hall Institute of Medical Research in Melbourne claimed an international breakthrough.

They isolated large volumes of neural stem cells capable of regenerating into new tissue, nerves and muscle, according to research published in the international journal Nature Thursday.

The discovery could also end the ethical controversy surrounding stem-cell research on cloned human embryos, which are destroyed when the cells are extracted.

Research team head Perry Bartlett said the work had proved the versatility of adult stem cells beyond a doubt.

"It's really taken us this last nine or 10 years to be able to find what the cell looks like, and having found it, we can now look at ways of being able to stimulate it into making new nerve cells with the possibility of replacing damaged or lost nerve cells in the adult brain," he said.

"It's important in the sense that there's been a debate about whether stem cells from adult tissues, whether that be brain or blood or elsewhere, do have the potential of embryonic stem cells to give rise to various tissues.

"I guess this is one of the very first unequivocal demonstrations that these cells are able to give rise to a larger number of cell types than was previously thought."

An internationally recognised expert on infant genetic disorders welcomed the breakthrough, but cast doubt on whether it would ease the controversy over the use of stem cells taken from cloned embryos.

Hugo Moser, head of neurology and paediatrics at Johns Hopkins University Hospital in the United States, said mature adult stem cells would prove less useful to researchers that ones taken from embryos.

"The experience has been, and it makes logical sense, that the adult cells have some capacity of turning themselves into something else, but they're not as good at it as embryonic stem cells," he said.

The Australian researchers said they were the first in the world to extract mouse neural stem cells pure enough for scientists to be able to experiment with their versatility.

PhD student Rodney Rietze developed a way of sifting through the cells lining the brain's cavities to find the elusive neural stem cells with 80 percent purity, compared to the previously achieved five percent purity.

"We mixed these cells with muscle cells in the test tube, and we found that the majority of these cells within three to four days turned into muscle cells, " Bartlett said.

"The big question has been, can we use these new stem cells to repopulate or repair nerve cells lost after injury or disease?"

The ultimate aim will be to develop a drug to stimulate this regrowth, avoiding the need for surgery to transplant cloned embryonic stem cells.

"With certain neurological conditions, like injury or stroke, you wouldn't want to be going in and transplanting tissue to a site which was already compromised," Bartlett said.

If adult stem cells could be used to restore nerve function lost through diseases such as Parkinson's or Alzheimer's, it would also get around the likely problem of cloned embryonic stem cells being rejected by the body's immune system, he said.

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