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Tollwutig
06-06-2007, 04:33 PM
This is deserving of it's own topic:

NEW YORK — In a leap forward for stem cell research, three independent teams of scientists reported Wednesday that they have produced the equivalent of embryonic stem cells in mice without the controversial destruction of embryos.

They got ordinary skin cells to behave like stem cells. If the same could be done with human cells _ a big if _ the procedure could lead to breakthrough medical treatments without the contentious ethical and political debates surrounding the use of embryos.

Experts were impressed by the achievement.

"I think it's one of the most exciting things that has come out about embryonic stem cells, period," said researcher Dr. Asa Abeliovich of Columbia University in New York, who didn't participate in the work. "It's very convincing that it's real."

But he and others cautioned that it will take further study to see whether this scientific advance can be harnessed for creating new human therapies. For one thing, the procedure used in the mouse studies wouldn't be suitable. And it's simply not known whether the mouse results can be reproduced with human cells.

"We have a long way to go," said John Gearhart of Johns Hopkins University, a stem cell researcher who also wasn't involved in the new work.

In any case, scientists said, the advance does not mean that research that involves getting stem cells from human embryos should now be abandoned. "We simply don't know which approach ... will work the best," said researcher Konrad Hochedlinger of the Harvard Stem Cell Institute, who led one of the three teams.

Embryonic stem cells are prized because they can develop into all types of tissue. So experts believe they might be used for transplant therapies in people who are paralyzed or have illnesses ranging from diabetes to Parkinson's disease.

To harvest human embryonic stem cells, embryos must be destroyed, an action many people oppose.

Scientists have long hoped to find a way to reprogram ordinary body cells to act like stem cells, avoiding the use of embryos altogether. The new mouse studies seem to have accomplished that. Past experiments seeking alternative routes to getting stem cells have generally involved tampering with an embryo or egg.

At a press conference Wednesday, Hochedlinger and a member of a second team said their work was not an attempt to evade the ethical objections to embryo destruction. Instead, they said, the goal was to learn how cell reprogramming works.

But in a telephone interview, a prominent critic of embryonic stem cell research welcomed the new work on ethical terms.

"This is what we were looking for people to explore because it may provide all the advantages of embryonic stem cells without the moral problem," said Richard Doerflinger, deputy director of pro-life activities for the U.S. Conference of Catholic Bishops. "So I'm very encouraged."

Hochedlinger and colleagues present their work in the inaugural issue of the journal Cell Stem Cell. (The first word in the journal's name refers to its publisher, Cell Press).

The other two teams reported their results Wednesday on the Web site of the journal Nature. Rudolf Jaenisch of the Whitehead Institute in Cambridge, Mass., is the senior author of one paper, and the work behind the other paper was led by Shinya Yamanaka of Kyoto University in Japan.

The new work builds on a landmark paper Yamanaka published last August. He found that by slipping four genes into mouse skin cells called fibroblasts, he could make the altered cells behave much like embryonic stem cells in lab tests.

But these so-called "iPS" cells still showed significant differences from embryonic stem cells. The three new papers report on creating iPS cells that proved virtually identical to stem cells in a variety of lab tests.

The technique used in the mouse studies could promote cancer in any patients getting therapy based on iPS cells, so researchers emphasized that a new approach that avoids that hazard would have to be developed.

Gearhart called that a major issue to be resolved. In addition, he said, scientists still must show that these cells can give rise to many cell types in the lab, as embryonic stem cells can.

And all this must be accomplished in human cells _ a difficult task, he said, because introducing genes into human cells is a major challenge.

If the technique can be harnessed for people, the iPS cells and the tissue they develop into would provide a genetic match to the person who donated the skin cells. That would make them suitable for transplant to that person, theoretically without fear of rejection.

A good achievement but if you'll notice that they new cells still have to be proven to be as effective as Embryonic stem cells, and that it would also have to be replicated in Humans.

bayushisan
06-06-2007, 05:55 PM
This is deserving of it's own topic:



A good achievement but if you'll notice that they new cells still have to be proven to be as effective as Embryonic stem cells, and that it would also have to be replicated in Humans.

A question if you will. Haven't there been more than forty plus medical breakthroughs since 2000 using donated adult cells? From what this reasearch shows it seems like they're trying to replicate the cells that have shown to have had the greatest successes so far.

EDIT: I may have misunderstood the article and if so I apologize. It was a but confusing, at least I though so anyway

Tollwutig
06-06-2007, 08:39 PM
A question if you will. Haven't there been more than forty plus medical breakthroughs since 2000 using donated adult cells? From what this reasearch shows it seems like they're trying to replicate the cells that have shown to have had the greatest successes so far.

EDIT: I may have misunderstood the article and if so I apologize. It was a but confusing, at least I though so anyway

To me it's kinda dumbed down because I usually read the Science journals when I find something like this. No these aren't adult stem cells.

This is taking a regular skin cell and "reprogramming" it to act like an embryonic stem cell.
Adult stem cells already have a partial destiny programmed in, i.e. you get an epithelialn (skin) cell to become a connective tissue (bone) cell. Embryonic stem cells have the potential to differentiate into any cell in the body. and thus the potential to grow any organ.

KN
06-06-2007, 08:45 PM
Which of course if far more desirable than using fertilized ovi, as this can be completely automated, providing a large amount of usable tissue is available.

Happy tiems ^__^

Tollwutig
06-06-2007, 08:56 PM
Which of course if far more desirable than using fertilized ovi, as this can be completely automated, providing a large amount of usable tissue is available.

Happy tiems ^__^

Since they are using skin cells there are always a lot of starting material.:D Also they could pull the cells with the correct DNA already in them.