New insight into "stem'' cells in brain, marrow
April 3, 1997
5.53 p.m. EST (2253 GMT)
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WASHINGTON -- Contrary to what scientists have long believed,
the central nervous system has stem cells capable of dividing
and forming other kind of cells, researchers reported Thursday.
The finding has potential implications for people with
Parkinson's disease, spinal cord injury, and other central
nervous system disorders.
The work will appear Friday in the journal Science, which
contains several reports on stem cells and their potential
for regeneration, repair and healing.
"Stem cells'' are precursors of specialized cells. For
instance, stem cells in bone marrow give rise to blood cells.
But it has long been thought that one reason the adult central
nervous system could not repair itself was because stem cells
could not divide and form other types of cells. Fetal stem
cells do develop or differentiate into one of three kinds of
nerve cells -- a neuron, astrocyte or oligodendrocyte.
Now, Ronald McKay at the National Institute of Neurological
Disorders and Stroke has shown that these fundamental cells
can be grown in culture with growth factors and directed to
act like fetal cells.
Although he does not yet know the exact chemical signals
that this process requires, he has established that the adult
cells are essentially the same as fetal cells and he has
identified some proteins involved in cell differentiation.
Scientists' ability to culture these cells will enable them
to study their role in brain development and possibly to develop
ways of replacing injured brain cells. This may eventually
help treat Parkinsons and other brain diseases.
In a separate report in Science, a team from Allegheny
University of the Health Sciences in Pittsburgh focused on
another kind of basic cell, known as Marrow Stromal Cells,
found in bone marrow.
Bone marrow transplants are already used to derive stem
cells, which make blood cells. But now Dr. Darwin Prockop at
Allegheny and his colleagues report that they are exploring
how to use these marrow stromal cells, which are the
precursors of bone and connective tissue cells.
The goal is to develop ways of treating diseases ranging
from osteoporosis, which afflicts the old, and "brittle
bone disease'' that afflicts the young.
One approach would be to replace flawed cells with healthy
ones that could produce normal bone and tissue. Another
approach could be to remove some of those cells from a
patient, genetically re-engineer them to treat a flaw that
causes diseases, and then implant them back into the patient.
[log in to unmask] That man may last, but never lives,
Who much receives, but nothing gives;
HomeBoy #Parkinsons Whom none can love, whom none can thank,--
Creation's blot, creation's blank.
John Cottingham Thomas Gibbons (1720-1785): When Jesus dwelt.
