Stem Cells without Side Effects

[n2doc]

Researchers have created healthy stem cells from adult cells--no embryo required.
By Lauren Gravitz

Last year, researchers announced one of the most promising methods yet for creating ethically neutral stem cells: reprogramming adult human cells to act like embryonic stem cells. This involved using four transcription factor proteins to turn specific genes on and off. But the resulting cells, called induced pluripotent stem (iPS) cells for their ability to develop into just about any tissue, have one huge flaw. They're made with a virus that embeds itself into the cells' DNA and, over time, can induce cancer. Now, scientists at Harvard University have found a way to effect the same reprogramming without using a harmful virus--a method that paves the way for tissue transplants made from a patient's own cells.

The first generation of iPS cells was created using a retrovirus to insert the four transcription factors into skin cells. Because a retrovirus, by definition, inserts itself permanently into its host's DNA, this ensured that the transcription factors were transferred,, but it also led to the propagation of the virus itself. Furthermore, since the virus confers self-renewal capabilities to its new host cell, many believed that the retrovirus might be required for iPS cells to reproduce.

New research by Konrad Hochedlinger and his colleagues at Harvard University, the Harvard Stem Cell Institute, and the MGH Center for Regenerative Medicine shows that a different type of virus--an adenovirus--can make the transfer in mouse cells without permanently integrating itself. The resulting iPS cells can divide indefinitely but show no trace of the virus--just a temporary infection that disappears within a short time. "That means that the four transcription factors themselves are sufficient to induce pluripotency in adult cells," Hochedlinger says.

Many view the creation of genetically unmodified iPS cells as regenerative medicine's magic bullet. The cells are not derived from embryos, so researchers can circumnavigate the ethical gray areas. And if these cells turn out to be as potent as embryonic stem cells, they could be used to help regrow tissues damaged in conditions ranging from paralysis to Parkinson's disease to diabetes. If they can be grown from a patient's own cells, they could furthermore be transplanted without triggering immune rejection.

Until now, however, creating iPS cells without integrated viruses had been a major hurdle for stem-cell researchers. Although Hochedlinger has overcome that hurdle, he says there is still some distance to travel. While retroviral techniques allow scientists to turn about one in every 1,000 skin cells into an iPS cell, the adenovirus is far less efficient: only one in every 10,000 to 100,000 fetal liver cells can be converted. "It may be that people have tried adenoviruses before but missed the iPS cells because the efficiency is so low," Hochedlinger says. "We ourselves tried to use adenoviruses a year ago, and it didn't work."

more:
http://www.technologyreview.com/Biotech/21430/

[Warren Stupidity]

1. What a waste of valuable research talent and money.

Everytime I read about one of these 'we created stem cell like stuff just as good as real stem cells' I want to go dope slap somebody.

Embryonic stem cells - from embryos that are going to be thrown out - are cheap and easy to obtain. These other 'just as good as' things are neither. The money and talent ought to be going into using stem cells to make sick people healthy, not pandering to the religously impaired idiots.

[Fire_Medic_Dave]

2. It's a shame the Bush gets credit for being the President that lifted the ban on stem cell research.

[Fire_Medic_Dave]

3. No one is stopping them from using private stem cell lines.

Or from using private or state funds. If the research is so promising why is the money so hard to come by?

David

[Celebration]

4. any private funding is hard to come by when it is basic reasearch

That is why the government needs to fund basic research, and let the private sector fund things that are further along and more easily marketable.

Also, please remember that when no federal funds can be used for embryonic stem cells research, that is strictly applied. So, whole new laboratories and facilities need to be set up. Seriously, it is stricter than keeping a kosher kitchen. One can't even use the same sink in a labortory if the depreciation on that sink is somewhere rolled into the administrative cost of another grant that got federal money. The rules are that strict. Needless to say, buying a whole new building with a different lab gets a wee bit expensive.

So you have something against federally funded embryonic stem cell studies? Man, you are really out of step with folks here.

[Fire_Medic_Dave]

6. Do you still beat your dog?

When did I say I was against federally funded embryonic stem cell studies?

David

[Celebration]

7. you didn't say one way or another

which is why I asked-- I asked in good faith because your other response seems based on the talking points of those who reject federal funding of embryonic stem cell research (private money can pay for it, yada, yada)...

[Fire_Medic_Dave]

8. You didn't ask in good faith, which makes you well...

Your, "Man, you are really out of step with folks here." was kind of a dead give away. Bill Clinton should have taken care of this when he was in office and it's ridiculous that more private and state money hasn't been made available for embryonic stem cell research considering the current state of federal funds. I don't hold fault with the people who are working with stem cells of any sort unlike the person I was responding to.

David

[dropkickpa]

5. Not a waste at all

ESC's are not a magic bullet, the main objection in the biomedical research community is that they are being denied even the opportunity to research their usefulness by puritannical fundie lawmakers. Mouse ESC research can only do so much!