Naturally dead embryos yield stem cells - 'Stalled' embryos could be new source of cell lines.

news@nature.com ^ | 21 September 2006 | Alison Abbott

[neverdem]

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Published online: 21 September 2006; | doi:10.1038/news060918-10

Naturally dead embryos yield stem cells

'Stalled' embryos could be new source of cell lines.

Alison Abbott

The new technique could remove the need to deliberately destroy embryos for stem cells.Punchstock

Researchers have succeeded in developing a human embryonic stem-cell line from an embryo that had died naturally.

The development may offer a non-problematic source of embryonic cells in countries such as Germany and the United States where the law does not allow the use of cell lines whose creation caused the destruction of embryos.

If the work bears fruit, researchers could instead create stem-cell lines from embryos that had naturally stopped developing during in vitro fertilization procedures.

"Fewer than half of human eggs fertilized in vitro do not develop to the 'blastocyst' stage, which is required for implantation," says Miodrag Stojkovic, who led the project at the University of Newcastle in the UK. He is now deputy director of the Principe Felipe Research Centre in Valencia, Spain. "There are many different reasons why they don't survive."

Arrested development

Stojkovic used 161 donated embryos in his study, which is scheduled to be published in Stem Cells¹. The embryos came from two local in vitro fertilization clinics. Of these, 29 were developing, 119 'arrested' (stopped dividing) 3 to 5 days after fertilization, and 13 arrested 6 to 7 days after fertilization.

If everything is confirmed, I don't see how anyone could attack such cell lines as unethical.  Hans Schöler Max Planck Institute for Molecular Biomedicine in Münster, Germany

Arrested embryos were monitored for up to two days to make sure they would not revive, thus meeting the standard embryologists' criteria for being dead.

Stojkovic's team derived healthy embryonic stem-cell lines from one of the 13 late-arrested embryos, along with eight of the normally developing embryos. They had no success using embryos that arrested early.

Only a few of the cells, called blastomeres, in the arrested embryos had remained healthy — many had distorted shapes or damaged chromosomes. "But there were enough undamaged blastomeres to allow us some limited success," says Stojkovic.

The efficiency of the process is very low at the moment, but scientists may be able to improve on this in the future, he says.

Maximum potential

Stojkovic says he did not set out to find ways to address the concerns of politicians, but rather to maximize the use of donated material. "I think that if you are given donated human embryos for research, you have a moral duty to use as much of the material as possible — and we have now found that we don't have to discard half of the embryos immediately, as we used to."

Nevertheless, stem-cell scientists in countries with restrictive embryo-protection laws are excited by the potential of Stojkovic's achievement. "There is no destruction of an embryo," says Hans Schöler, a director of the Max Planck Institute for Molecular Biomedicine in Münster, Germany. "If everything is confirmed, I don't see how anyone could attack such cell lines as unethical."

Schöler has been critical of another recent paper on 'ethically acceptable' embryonic stem cells. That paper, by Robert Lanza and his colleagues from Advanced Cell Technologies in Worcester, Massachusetts, proved in principle the idea that human embryonic stem-cell lines can be created without destroying embryos, but did not actually do it (see ''Ethical' stem-cell paper under attack'). This method, which Lanza is pursuing, could theoretically be used to create an embryonic stem-cell line from an embryo that grows into a healthy baby.

So why have researchers not done this before? Stojkovic says the procedure is difficult, and puts his success down to the methodology. "We had to try a lot of tricks to coax the blastomeres to grow," he says, including removing the sheath of the embryo and using very specific culture conditions.

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References

1. Zhang X., et al. Stem Cells Express, (in the press) (2006).

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http://news.nature.com//news/2006/060918/060918-10.html

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[Howlin]

I can hardly wait to read why these can't be used either.

[onyx]

You cynic...lol.

[Howlin]

You know it's coming.

[onyx]

LOL

[neverdem]

SC Ping

[Mogollon]

Their great for causing cancer dontcha know.

[hocndoc]

I could accept this as an ethical alternative, if the cells are pleuripotent and not totipotent.

Of course, like all embryonic cells, they're only good for the basic research, in order to discover the factors and stimulants necessary to obtain what will be needed/used in the human body: adult stem cells and progenitor cells. Much better than transplants: activate the body's own cells and stimulate them to achieve repair or regeneration.

[Sir Francis Dashwood]

Frankenstein...

[Tinian]

The development may offer a non-problematic source of embryonic cells in countries such as Germany and the United States where the law does not allow the use of cell lines whose creation caused the destruction of embryos.

I don't know about Germany, but U.S. law does allow research using stem cell lines created by the destruction of human embryos. U.S. law only forbids the federal funding of such research.

If Nature can't even get this basic fact straight, how on earth can I trust their science?

[ovrtaxt]

Cool. This research is flying so fast it's astounding! Every week, it seems I read about something I didn't ever expect to see.

[right-wingin_It]

DUH...embyos belong in a womb--That's Natural...This "natural death" they claim in this article is a load of crap!!!

[syriacus]

From the article:

"There are many different reasons why they don't survive."

I guess the scientists have figured out what stalled the embryos' development and will be able to make sure that using the cells is safe.

Right?

[GingisK]

'Stalled' embryos could be new source of cell lines....

Yeah, and maybe they harbor the reason the embryo died in the first place.

[hocndoc]

email 'em at "news@nature.com"

[Coleus]

they can't be used because, after 25 years, embryonic stem cell research has been a failure and yielded no cures. when are people like you going to wake up?

[Sloth]

Good catch.

[RightWhale]

This source cannot represent a lot of material. 161 such embryos would be a microscopic amount of stem cells.

[Coleus]

Embryonic stem cell use has been stalled and dead for 25 years since the research started. It is dead because it's use failed and actually killed people. It's time to appropriate funds and energy to adult stem cell research which has yielded, to date, 72 cures.

[Irish_Thatcherite]

The once formidable anti-life empire is now crumbling.