LONDON, DEC. 1, 2000 (ZENIT.org).- Scientists have shown it is possible to
convert bone marrow tissue into brain cells in an experiment that could
undermine arguments for using human embryos to treat patients suffering
from neurological disorders such as Parkinson's disease, The Independent
reported.

Two independent teams of U.S. researchers have demonstrated that the bone
marrow of adult mice can be used as a rich supply of stem cells -- the
master cells of the body -- which developed into functional nerve cells in
the brain, the newspaper said.

The findings indicate that it might be possible to use human bone marrow as
a source of stem cells for repairing damaged tissues in a range of organs,
from heart and kidneys to liver and brain, which would be ethically more
acceptable than creating embryos for the purpose, The Independent noted.
Later this month, members of Parliament are scheduled to take a free vote
on whether to extend the exploitation of embryos for stem-cell research.

The pioneering research, published today in the journal Science, was
carried out by a team from the U.S. National Institute of Neurological
Disorders and Stroke near Washington, D.C., and a second group from
Stanford University in California. Gerald Fischbach, the director of the
institute, said the findings could have "monumental" implications.

The neurological institute's team, led by Eva Mezey, injected bone marrow
cells from adult male mice into newborn female mice. The presence of the
male Y chromosome allowed the scientists to track the movements of the
injected stem cells in the female body, The Independent said.

At the end of four months they found that a significant number of cells had
migrated to several regions of the brain, such as the outer cortex, the
hypothalamus and the striatum, and had fully differentiated into working
nerve cells.

"This suggests that stem cells from elsewhere in the body can enter the
brain and differentiate into neuronal cells," Mezey said.

The second study, led by Helen Blau of Stanford, used bone marrow stems
that had been labeled with a fluorescent dye. The group found that if
labeled bone marrow cells from adult mice were injected into mice lacking
any functioning bone marrow, the cells migrated to the brain and took up
residence in regions such as the cortex, hippocampus and cerebellum.

The researchers said: "These studies suggest that bone marrow, which is an
easily available source of cells, could be used as a source of neurons to
replace those damaged or lost in neurological disorders. The fact that even
bone marrow from adult mice generated neuronal cells shows an unexpected
amount of flexibility in older cells and suggests that patients with brain
disorders could be treated with their own cells."
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