Cells transformed in promising research

<http://edition.cnn.com/2008/HEALTH/08/27/cell.identity.ap/index.html?eref=rss_latest>http://edition.cnn.com/2008/HEALTH/08/27/cell.identity.ap/index.html?eref=rss_latest

Story Highlights
    * Ordinary pancreas cells were changed into insulin-producing 
cells in living mice
    * Suggests doctors might be able to use a patient's own cells to 
treat disease or injury
    * The approach is not ready for people, researchers say
NEW YORK (AP) -- Talk about an extreme makeover: Scientists have 
transformed one type of cell into another in living mice, a big step 
toward the goal of growing replacement tissues to treat a variety of diseases.
New research suggests doctors could use a patient's own cells i


New research suggests doctors could use a patient's own cells instead 
of embryonic stem cells to treat disease.
[]


The cell identity switch turned ordinary pancreas cells into the 
rarer type that churns out insulin, essential for preventing 
diabetes. But its implications go beyond diabetes to a host of 
possibilities, scientists said.

It's the second advance in about a year that suggests that someday 
doctors might be able to use a patient's own cells to treat disease 
or injury without turning to stem cells taken from embryos.

The work is "a major leap" in reprogramming cells from one kind to 
another, said one expert not involved in the research, John Gearhart 
of the University of Pennsylvania.

That's because the feat was performed in living mice rather than a 
lab dish, the process was efficient and it was achieved directly 
without going through a middleman like embryonic stem cells, he said.

The newly created cells made insulin in 
<http://topics.edition.cnn.com/topics/Diabetes>diabetic mice, though 
they were not cured. But if the experiment's approach proves viable, 
it might lead to treatments like growing new heart cells after a 
heart attack or nerve cells to treat disorders like ALS, also known 
as Lou Gehrig's disease.

Douglas Melton, co-director of the Harvard Stem Cell Institute and a 
researcher with the Howard Hughes Medical Institute, cautioned that 
the approach is not ready for people.


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    * TIME.com: 
<http://www.time.com/time/health/article/0,8599,1828345,00.html?imw=Y>Scientists
 
reach stem cell milestone

He and his colleagues report the research in a paper published online 
Wednesday by the journal Nature.

Basically, the identity switch comes about by a reprogramming process 
that changes the pattern of which genes are active and which are shut off.

Scientists have long hoped to find a way to reprogram a patient's 
cells to produce new ones. Research with 
<http://topics.edition.cnn.com/topics/stem_cell_research>stem cells, 
and similar entities called iPS cells that were announced last year, 
has aimed to achieve this in a two-step process.

The first step results in a primitive and highly versatile cell. This 
intermediary is then guided to mature into whatever cell type 
scientists want. That guiding process has proven difficult to do 
efficiently, especially for creating insulin-producing cells, Gearhart noted.

In contrast, the new method holds the promise of going directly from 
one mature cell type to another. It's like a scientist becoming a 
lawyer without having to go back to kindergarten and grow up again, 
Melton says.

So, he says, someday scientists may be able to replace dead nerve or 
heart cells in people by converting some neighboring cells. At the 
same time, he stressed that it's still important to study embryonic 
stem cells and iPS cells.

The Melton team started its work with pancreas cells that pump out 
gut enzymes used in digestion and turned them into pancreatic "beta" 
cells, which make insulin.


Health Library

    * MayoClinic.com: Diabetes

The researchers destroyed beta cells in mice with a poison, giving 
the mice diabetes. Then they injected the pancreas with viruses that 
slipped into the enzyme-making cells. These viruses delivered three 
genes that control the activity of other genes.

Just three days later, new insulin-secreting cells started to show 
up. By a week after that, more than a fifth of the virally infected 
cells started making insulin. That shows "an amazingly efficient 
effect," commented Richard Insel, executive vice president of 
research at the Juvenile Diabetes Research Foundation.

Scientists found evidence that the newcomers were converts from 
mature enzyme-making cells. They identified the new cells as beta 
cells by their detailed appearance and behavior, and Melton said 
they've continued functioning for months.

The new cells didn't fully replenish the insulin supply, but maybe 
there were too few of them, or they were hampered by not forming 
clusters like ordinary beta cells do, researchers said.

The work brings "more excitement to the idea of using reprogramming 
as a way to treat diabetes," said researcher Mark Kay of Stanford 
University, who is studying the approach with liver cells.

Christopher Newgard, who studies beta cells at Duke University 
Medical Center, called the work convincing but cautioned that 
significant scientific questions remained about using the approach in 
treating disease.

Melton, who began his diabetes research in 1993 when his infant son 
was diagnosed with the illness, said he's obsessed with trying to 
find a new treatment or cure for Type 1 diabetes, in which beta cells 
are destroyed.

"I wake up every day thinking about how to make beta cells," he said.

Melton said he hopes drugs can replace the virus approach because of 
concern about injecting viruses into people.

As for converting other kinds of cells, scientists noted that the two 
cell types in the mouse experiment are closely related, and it 
remains to be shown whether the trick can be achieved with more 
distant combinations. In any case, scientists would have to deliver 
different reprogramming signals to other kinds of cells, Melton said.



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Holy Postage ~ Share your faith


Lord, may everything we do begin with Your inspiration and continue 
with Your help,
so that all our prayers and works may begin in You and by You be happily ended.
We ask this through Christ our Lord.
Amen.

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