Stories tagged Stem cell research

President Obama has signed an executive order that expands federal funding for some embryonic stem cell research.

In 1991, President Bush signed an executive order that forbade the National Institutes for Health from funding research on embryonic stem cells beyond the 60 or so stem cell lines that already existed at the time. President Obama's order will allow scientists to use federal money to to do research on any stem cell lines, although government money still can't be used to generate new stem cell lines. (The creation of a stem cell line requires the destruction of a human embryo.)

More Buzz stories on stem cell research...

CNN's "explainer" feature on the promise of stem cell research

Oct
13
2008

A display on adult stem cells, here at the SMM: In fact, this exhibit features Catherine Verfaillie herself.    (Good looking out, BK)
A display on adult stem cells, here at the SMM: In fact, this exhibit features Catherine Verfaillie herself. (Good looking out, BK)Courtesy bryankennedy
Following the results of an evaluation by a panel of experts at the University of Minnesota, the magazine New Scientist published an article last week announcing that some of the data used in a groundbreaking study on adult stem cells had been falsified.

The study, performed at the University of Minnesota under the supervision of Catherine Verfaillie, is part of a line of research that seemed to indicate that adult stem cells, taken from bone marrow, are pluripotent—that is that they have the potential to develop into any type of cell. Previously, only embryonic stem cells were thought to be pluripotent, and Verfaillie’s research looked like it could eventually offer an alternative to the ethically complicated use of embryonic cells for research (which requires the destruction of an embryo).

Unfortunately, other scientists had trouble replicating Verfaillie’s results, which were published in the journal Nature. New Scientist began examining the research done by Verfaillie and her team, and found that key images in the research appeared several times in papers for different experiments, and, in the case of a related study in the publication Blood, were used twice in the same paper, but had been visually altered slightly, and flipped 180 degrees. New Scientist reported their findings to the University, which began a formal investigation of the matter.

The University just recently completed the investigation, and found that data in the blood article had indeed been falsified (the images in particular), by a former PhD student of Verfaillies’, Morayma Reyes. The University and Catherine Verfaillie have asked Blood to redact the study.

Verfaillie has stated that she was unaware of the problems with the published study, and while she didn’t believe that the data was deliberately falsified, she takes ultimate responsibility for the errors.

Reyes, who now works as an assistant professor at the University of Washington, denies that the images represent deliberately altered data, and blames the errors on inadequate supervision and training. She claims that she had neither the equipment (photo editing software) nor knowledge required to alter the images. The differences in the reoccurring images were likely the result of the inadvertent use of the image adjusting tools built into lab equipment, she says, and the duplication of a figure within the Blood paper was accidental. Reyes also feels that she has been treated unfairly by the University, and that the expert panel in the investigation demonstrated a clear “lack of expertise” in the field of stem cell biology.

Reyes’ full position can be read here. The University’s response can be found here.

The altered images, Reyes asserts, shouldn’t change the results of the paper, but the whole incident brings up some interesting issues on the process of vetting science. While the errors in the paper never should have made it past Verfaillie and the rest of her team, the process of peer review should have caught them anyway. Generally, before research is published in a scientific journal, the editors select several scientists in the particular field of the paper to evaluate and comment (often anonymously) on the paper. The review panel is meant to confirm that the methodology of the experiments and the interpretation of the results are sound. Research can then be recommended (or not) for publication.

Publishing research essentially formally submits it to the scientific community, and it’s common for other scientists to attempt to replicate experiments, especially if a study makes particularly striking claims (like adult stem cells being pluripotent). The work of other scientists in replicating results is, obviously, essential to the scientific method—in this case is was what finally drew attention to some of the irregularities in Verfaillie’s team’s work.

Reproducibility can be a tricky thing, though—difficulty in repeating results doesn’t necessarily mean that they aren’t reproducible. (Here’s a good article on repeating and reproducing results.) But the problems in reproducing these results drew attention to the questionable data, which brought up another aspect of scientific vetting: the University’s investigation into academic misconduct. If the problems with reproducibility seem to come from data being changed, added, or omitted to strengthen a conclusion, then there could be a serious problem. This sort of misconduct undermines scientific progress, and can call into question the reputation of the institution it came out of and the validity of other research performed there. And if Morayma Reyes seems a little extra defensive in her letter, it’s understandable, because being accused of academic misconduct is a big deal, and no good for your career and future work.

The subject of the research further complicates the situation—this isn’t the first time issues of academic dishonesty have come up with regards to stem cell research. In 2006, a Korean scientist’s claims that he had cloned human embryos (thereby eliminating the need to destroy new embryos for stem cells) turned out to be based on lies. There’s a fear that the potentially huge medical payoff of stem cell research, as well as the ethical debate surrounding the use of human embryonic stem cells, could lead to science that is less than completely thorough, or even situations like the Korean controversy. And that’s bad for science in general. There’s also the thought that errors that are unintentional (as may be the case with Reyes’ images) could be the result of “pathological science,” where results are steered in a particular direction by scientists because of “subjective effects, wishful thinking, or threshold interactions.” It doesn’t have the same ethical problems, but pathological results aren’t a whole lot better for science than straight-out misconduct, and it’s a serious potential pitfall with the benefits of stem cell research waiting out there as temptations.

So there you go. It looks like things are, for the most part, being handled appropriately in this situation, but it’s an interesting window into scientific process.

Any thoughts? Does it seem like the vetting process of science is lacking in some way? Or is it maybe too thorough? Professor Reyes, I imagine, would argue that too much has been made of this situation, and there are many who argue that the process of peer review limits the communication and dissemination of scientific ideas.

Or, even better, does it seem like I got something wrong here?

Let’s have it, Buzzketeers.

Science debate 2008
Science debate 2008Courtesy Science debate 2008.
Follow the link below to see the how presidential candidates Barack Obama and John McCain answered a series of questions about science policy, covering topics including stem cell research, global warming, renewable energy research, science education, space exploration and more. Obama's answers were submitted in August, and McCain's this past Monday.

Click here for the candidates' answers to the top 14 science questions facing America.

Dr. Hwang Woo-suk, the disgraced Korean stem cell researcher, is back in the news again with a report that he has successfully cloned dogs.

Sep
09
2007


In your dreams pal: A normal human can't keep up the facade. (photo by hanhutton on flickr.com)
I’m not sure… Half man, half spider would probably be okay, as long as you didn’t end up with a bunch more legs. Half man, half fly clearly didn’t work out. Half man, half dolphin might work. Half man, half wolf would have to be cool, plus I hunt rabbits that way already.

What? Oh, sorry, I was just thinking about something. Say, did any of you hear the news out of England? The UK government has approved the creation of human-animal hybrids.

It’s about time.

Why do I say this? Well, I’ll sum it up in two points:
1) How many octopus-like suckers have I got on my arms? Zero.
2) How long have I wanted octopus-like suckers on my arms? Forever.

British scientists are quick to point out, though, that they won’t be creating viable creatures, only embryos, and, furthermore, only a very small amount of animal DNA will be present in the embryo. Human DNA would be transferred to an animal egg (of, say, a rabbit or a cow) that had already had most of the genetic material removed. The hybrids would be allowed to grow to only a very early stage, just long enough to study the development of the stem cells.

Or so they say. This slideshow has recently been leaked onto the Internet, and it offers some pretty compelling (and, just a warning, possibly upsetting) evidence to the contrary:

So now you’ve seen the future. What do you think? Are those gentlemen-dogs better off?

Jun
09
2007

New source of stem cells without destroying embryos.

Stem cells from mouse tails: Photo adapted from Kadath
Stem cells from mouse tails: Photo adapted from Kadath

Stems cells can self-renew or go through numerous cycles of cell division while maintaining their undifferentiated state. Stem cells also have the capacity to differentiate into any mature cell type. These unique properties make stem cells very promising in research toward fixing damaged nerves, diabetes, and Alzheimer's. But research involving stem cells has been limited because obtaining stem cells involved destroying human embryos.

Piece of mouse's tail transformed into living mouse.

Researchers found a way to use skin cells from an adult mouse to create stem cells like that of an embryo.

Four genes, which code for four specific proteins known as transcription factors, are transferred into the cells using retroviruses. The proteins trigger the expression of other genes that lead the cells to become pluripotent, meaning that they could potentially become any of the body's cells. Yamanaka calls them induced pluripotent stem cells (iPS cells). "It's easy. There's no trick, no magic," says Yamanaka. Nature.

Principle proven, but not for humans, yet.

But the iPS cells aren't perfect, and could not be used safely to make genetically matched cells for transplant in, for example, spinal-cord injuries. Yamanaka found that one of the factors seems to contribute to cancer in 20% of his chimaeric mice. He thinks this can be fixed, but the retroviruses used may themselves also cause mutations and cancer.

"This is really dangerous. We would never transplant these into a patient," says Jaenisch.

In his view, research into embryonic stem cells made by cloning remains "absolutely essential". ScienceBlogs.com

"Human embryonic stem cells remain the gold standard for pluripotent cells, and it is a necessity to continue studying embryonic stem cells through traditional means." Jaenisch, MIT.edu/news

Barriers to embryonic research are breaking

After more than two years of legal wrangling, California is free to spend over $3 billion during the next decade on stem cell research. California Institute for Regenerative Medicine (CIRM) is now free to raise some $300 million per year by selling bonds. New Scientist

In the United Sates Congress, the House gave final approval on Thursday to legislation aimed at easing restrictions on federal financing of embryonic stem cell research, but Democratic leaders in both chambers conceded they were short of the votes needed to override a veto threatened by President Bush. Any effort to override a veto would begin in the Senate, where the bill passed April 11 on a 63-45 vote. Even counting the three Senate Democrats who were not present for the vote, passage was one vote shy of the two-thirds majority needed to override a veto. New York Times.

Research paper in Stem Cell journal

With the federal government refusing to fund research into new embryonic stem cell lines, reports this week of a process that created them without destroying embryos in the process had scientists excited. But critics are claiming that the researchers overstated the implications of their work.

On July 25, 1997, researchers from Johns Hopkins University announced, at an international symposium on the ethics of human cloning and stem cells, that they had cultured human stem cells in their lab, using tissue taken from aborted human embryos. (Stem cells are the basic, unspecialized cells from which all other cells develop.) The researchers made the announcement before their research was published because they wanted to spark discussion that would establish guidelines for the ethical use of embryonic stem cells--a discussion that continues today.

Jul
19
2006

On Tuesday, the US Senate passed three bills regarding stem cell research.

Two were pretty uncontroversial: one encouraged stem-cell research using cells from sources other than embryos—adult bone marrow or hair follicles, or umbilical cord/placental blood. (The National Institutes of Health is already spending $571 million this fiscal year on this kind of stem cell research.) And one prohibited “fetal farming”—gestating fetuses for the purpose of providing tissue and other material for research.

The House of Representatives passed the bill about fetal farming, but voted down the bill promoting alternative stem cell sources. President Bush signed the ban on the commercial production of human fetal tissue into law today.

The third bill—which President Bush has just vetoed—would have expanded federal support of medical research using embryonic stem cells. Right now, researchers using federal funds can only study a handful of embryonic stem cell lines that existed before August 2001. The failed bill would have allowed federal funding for research on stem cells from thousands of unneeded embryos created in fertility clinics. (Couples with extra embryos resulting from fertility treatments would have had the option of donating them to research instead of having them destroyed by the clinic.) An override of the veto is unlikely.

What ARE stem cells?
Stem cells are simply cells that can develop into other types of cells. They can make copies of themselves indefinitely, and can become specialized for various body tissues. They are produced by embryos and also found in limited numbers in adults, but embryonic stem cells are pluripotent--they can become almost any kind of cell in the body--while adult stem cells are more limited. Scientists think they might be able to grow replacements for damaged tissues if they can coax stem cells to become the specific types of cells needed. Stem cells could someday provide treatments or cures for cancer, spinal cord injuries, burns, strokes, heart disease, Alzheimer’s and Parkinson’s, diabetes, and other ailments.

Mouse stem cells: (Courtesy NSF)
Mouse stem cells: (Courtesy NSF)

Why not use the pre-2001 stem cell lines?

In August 2001, the Bush administration and National Institutes of Health said that 60 stem cell lines had already been developed. Federal funds would be limited to research on those lines, and could not be used to create any more. But further investigation showed that less than 22 lines were actually available, and all of them had been maintained in culture dishes with blood products from rodents--scientists say the cells can’t ethically be used to treat people because of the danger of animal viruses and other contamination. Many of the lines aren’t aging well; if they don’t keep growing and dividing, they die, and some lines are accumulating mutations and other defects. Most research is limited to six of the stem cell lines. And they aren’t a very genetically diverse lot.

But the White House says,

"The use of mouse cells is standard scientific practice. ... As the Food and Drug Administration has indicated, the resulting stem cell lines can be carefully screened to ensure they are safe for use in any future clinical trials. Drug and biological products are routinely co-cultured with animal cells with no adverse consequences for the millions of people who have benefited from them."

Why not use private money?
Some labs have produced additional stem cell lines using private money, but researchers have to be scrupulous about segregating work on the newer cells from work done with federal money. The University of California, San Francisco, for example, is spending $5 million to set up a separate stem cell research lab where scientists can work without the federal restrictions. All the lab equipment they need already exists elsewhere on campus, but it can't be used for new stem cell work.

Some states see an opportunity in the federal restrictions. California announced that state money--$3 billion over 10 years--would be available for research into embryonic stem cells and therapeutic cloning. But the initiative is being fought in court. Connecticut has an 10-year, $100 million initiative. Illinois spent $10 million last year. New Jersey spent about $25 million in the last two years. And Maryland has approved a $15 million budget. But scientists in other countries are doing far more work with embryonic stem cells than scientists in the US. And losing out now means that the US could lose the eventual commercial applications developed through such research to the countries with looser regulations.

What's the issue with using embryonic stem cells?
Harvesting stem cells destroys a developing embryo. That's the crux of the whole issue. Those who oppose embryonic stem cell research say that the potential cures promised by stem cell research supporters offer false hope to some suffering Americans while encouraging the destruction of embryos to provide the cells. Members of the US Senate, debating earlier this week, expressed the gamut of opinions:

Senator Orrin Hatch (R-Utah) said,

"I do not question that an embryo is a living cell. But I do not believe that a frozen embryo in a fertility clinic freezer constitutes human life."

Senator Bill Frist (R-Tenn.), the Senate majority leader and a transplant surgeon, said,

"I believe that the progress of science and a pro-life position demand that Congress can send a message. I hope that we can redeem this loss of life in part by using these embryos to seed research that will save lives in the future."

Senator David Vitter (R-Louisiana) said,

"...I firmly believe that [neither] Congress, independent researchers nor any human being should be allowed, in effect, to play God by determining that one life is more valuable than another."

Senator Tom Coburn (R-Oklahoma), who is also a physician, said,

"The fact is, there is not one cure in this country today from embryonic stem cells."

Senator Tom Harkin (D-Iowa) said,

"So the choice is this ... throw [the embryos] away or use them to ease suffering and, hopefully, cure diseases."

Senator Sam Brownback (R-Kansas) said,

"We do not need to treat humans as raw material."

and

"It is immoral to destroy the youngest of human lives for research purposes. We don't need to do it."

Public opinion polls show that 70% of Americans support embryonic stem cell research. What do YOU think? Should the US government help fund it?

American universities (including University of California, San Francisco) are trying to create stem cell lines using cloned human embryos. (This is what South Korean researchers claimed to have done in 2004 and 2005; the lab later admitted that they'd fabricated their research.) Check the NPR story on who's in the business, how they're paying for it, and what the ethical issues are.