April 26, 2024

A “win-win” for ethics and science in latest stem cell advance

Harvard researcher morphs one cell into another

Douglas MeltonHarvard scientists have discovered that they can transform one cell directly
into another without an intermediate stage as an embryonic stem cell. This news
of this "feat of biological prestidigitation" was immediately lauded as an
ethical way to achieve the cures touted by embryonic stem cell scientists. "One
day, this may allow the doctor to replace the scalpel with a sort of genetic
surgery," a leading embryonic stem cell scientist, Robert Lanza said excitedly.
"If this can be perfected, it would represent one of the holy grails of
medicine."

What the Harvard biologists did was to identify three crucial molecular
switches which, when flipped, completely convert a common cell in a mouse
pancreas into the more precious insulin-producing ones that diabetics need to
survive. This raises the possibility that people suffering from diabetes, heart
disease, strokes and other ailments could be cured without the need for drugs,
transplants or other therapies.

"I see no moral problem in this basic technique," said Richard Doerflinger of
the US Conference of Catholic Bishops, a leading American opponent of embryonic
stem cell research. "This is a ‘win-win’ situation for medicine and ethics."

The experiments, which were reported in the journal Nature, were performed
upon mice, but Douglas Melton, the lead researcher, is confident that the
technique will work in humans as well.

The most remarkable feature of this latest advance in stem cell technology is
that, if successful, it completely bypasses the need for embryonic stem cells.
For several years, scientists have insisted that the way forward was the
creation of clones from which they would derive embryonic stem cells. These
would be nudged into becoming other cell types. Even last year’s advance by
Japanese scientist Shinya Yamanaka involved reprogramming a skin cells so that
they become embryonic-like stem cells. The Harvard technique may make either
strategy unnecessary.

As is the case with all work thus far with reprogrammed cells, Melton’s
experiments involve using viruses to flip the switches. Because of the risks
that approach would pose to humans, the team is looking for chemicals that might
effectively and safely replace the viruses. Stay tuned for further developments.
~ Harvard Stem Cell
Institute, Aug 27
; Washington
Post, Aug 28