Bloomberg August 7, 2008
Harvard Team Makes 10 Disease-Bearing Stem Cell Lines
By Rob Waters
Aug. 7 (Bloomberg)
-- Harvard University scientists have made lines of stem cells, able to turn
into any other cell in the body, from bits of skin or blood of 10 patients
with genetic diseases including muscular dystrophy and juvenile diabetes.
The findings will
help researchers decipher the workings of these diseases, enabling them to
study what happens as cells that carry a condition's genetic seeds develop
and age. The lines will be made available for a ``nominal fee'' to
researchers around the world, the Harvard scientists said.
Teams at the Harvard Stem Cell
Institute in Cambridge ,
Massachusetts , created the
lines using a technique that reprograms cells to give them the same power as
those from embryos to become any of the roughly 210 cell types in the body.
Their advance was described in a paper appearing today in the journal Cell.
The advance will
``allow researchers for the first time to get access'' to cells that are
defective in a particular disease ``and to watch the disease progress in a
dish, to watch what goes right or wrong,'' said Doug
Melton, a Harvard cell biologist and co-director of the institute.
The Harvard teams
created the new lines from tissue taken from 10 patients who ranged in age
from a 3-month-old child with a form of immune deficiency sometimes known as
``bubble boy disease'' to a 57-year-old with Parkinson's. Last week, another
Harvard team said they'd performed the same feat using the skin of two
patients in their 80s with the neurodegenerative condition known as Lou
Gehrig's disease.
Yamanaka Technique
The technique used
to create the stem cells, developed by Shinya
Yamanaka of Kyoto
University in
Japan , has captivated scientists
and transformed the research they're performing. The method involves using
viruses to insert four different genes into skin cells. The genes turn on a
process that causes the cells to revert to a primordial state similar to
embryonic stem cells.
Yamanaka announced
his breakthrough two years ago at a scientific meeting in
Toronto , when he described how he had been
able to endow skin cells from mice with the power of those from embryos.
Other advances followed rapidly. Last November, two research teams, one led
by Yamanaka and the other by James Thompson of the University
of Wisconsin in
Madison , announced independently that
they'd done the same thing with the skin of living people.
Research teams
around the world have rushed to use Yamanaka's technique for creating what he
calls induced pluripotent stem cells, or IPS cells, for two key reasons. It
is relatively easy and inexpensive to perform and it doesn't require the use
of human embryos or unfertilized eggs, both of which can be difficult to
obtain.
Ethical Concerns
Because human
embryos aren't used or harmed to create the IPS cells, the method sidesteps
ethical concerns that have dogged researchers. Religious and political
leaders including President George W. Bush have objected to traditional stem
cell research because embryos are destroyed in the process of creating the
lines.
Still, because
Yamanaka's technique uses viruses and genes that are known to cause cancer,
lines created with this method can't be used as treatments. They will allow
researchers to peer into the complex molecular and genetic processes that
occur in defective cells as they develop, giving them a greater understanding
of how and why disease begins.
``We are so ignorant
at the moment we don't even know if when patients gets diabetes, they all get
it the same way,'' Melton said in a conference call yesterday with reporters.
``There could be 50 different ways of getting Type 1 diabetes.''
Next Steps
George
Daley, the lead author of today's paper and a researcher at Children's
Hospital in Boston
who studies blood diseases, said he and his colleagues will now take the
newly minted stem cells and coax them to become blood cells of various types.
He said he hopes
that by comparing them with normal healthy blood, ``we can find the
particular development points where the defects arise and we can look at
gene-repair strategies.''
He and other
scientists also will be able to test thousands of existing drugs to see
whether any of them remedy the defects, he said.
Daley said the new
lines, and those developed in the future, will be maintained in a new
laboratory at Massachusetts General
Hospital in Boston .
Setting up the lab will enable other researchers to obtain the Harvard cells
for their own experiments, something that didn't happen quickly after
embryonic stem cells were first isolated in 1998, he said.
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