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Stem Cell Research: the Possibilities

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Author Topic: Stem Cell Research: the Possibilities  (Read 103 times)
Kristina
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« on: July 30, 2007, 02:15:25 am »

This topic is a replay of one I originally posted elsewhere:

Yesterday, Bush vetoed stem cell research bill because the Consituencey that controls him (as well as the government), the religious right, wanted him to, and in so doing, shut the door to all the people suffering from all the diseases that stem cell resarch can cure.

To all the people who have spinal chord injuries, he has told them he didn't care. To all the people who have heart disease and diabetes, he said he didn't care either. To all the people who need organ transplants, who have Alzheimers, cancer, any other disease that this technology could cure, Bush simply told them that he could care less. He left untold millions in not only America, but in the world to suffer, all because his administration is held hostage by religious zealots who don't even know what the facts are in this science, as usual, guided more by their fear than by anything that is reality.

Other countries are moving ahead of the United States on this, some states are already trying to fund it. But for any new technology to make serious advances, the United States has to be the leader on it, and it's sad to see the scicce of the U.S. controlled by people still stuck in the Dark Ages.

This is a setback, it is not the end. However, for all the people who will die from heart disease, cancer, Alzheimers and all the other diseases this treatment has the capacity to cure, they cannot wait for another year or two, while this research is expanded. Time is of the essence, and, make no mistake, this action, like many that Bush takes, will be the difference between life and death and will end up killing more people, who need these treatments now, not ten years frok now.

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Kristina
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« Reply #1 on: July 30, 2007, 02:17:08 am »

Bush vetoes stem-cell research bill on 'moral' grounds
MARY DALRYMPLE

Associated Press


WASHINGTON -- President George W. Bush cast the first veto of his 5-year presidency yesterday, saying legislation easing limits on federal funding for embryonic stem-cell research "crosses a moral boundary" and is wrong.

"This bill would support the taking of innocent human life in the hope of finding medical benefits for others," Mr. Bush said at a White House event where he was surrounded by 18 families who "adopted" frozen embryos not used by other couples, and then used those embryos to have children.

"Each of these children was adopted while still an embryo and has been blessed with a chance to grow, to grow up in a loving family. These boys and girls are not spare parts," he said.

The veto came a day after the Senate defied Mr. Bush and approved the legislation 63-37, four votes short of the two-thirds margin needed to override the veto. White House officials and Republican congressional leaders claimed it was unlikely that Congress could override the veto.

Mr. Bush's support was the strongest in the House, which was expected to take up the veto as early as late yesterday.

Mr. Bush has supported federally funded research on only those stem-cell lines created before Aug. 9, 2001 -- the date of his speech to the nation on the subject.

The President vetoed the measure shortly after it came to his desk. His position was politically popular among conservative Republicans, and it was sure to be an issue in the midterm congressional elections.

At the same time, Mr. Bush announced he had signed another bill, passed unanimously in the House and Senate, that would pre-emptively ban "fetal farming," the prospect of raising and aborting fetuses for scientific research.

Senate Majority Leader Bill Frist was quick to criticize the President's veto.

"I am pro-life, but I disagree with the President's decision to veto the Stem Cell Research Enhancement Act," said Mr. Frist. "Given the potential of this research and the limitations of the existing lines eligible for federally funded research, I think additional lines should be made available."

Said Mr. Bush: "As science brings us ever closer to unlocking the secrets of human biology, it also offers temptations to manipulate human life and violate human dignity. Our conscience in history as a nation demands that we resist this temptation.

"America was founded on the principle that we are all created equal and endowed by our creator with the right to life," he added. "We can advance the cause of science while upholding this founding promise. We can harness the promise of technology without becoming slaves to technology. And we can ensure that science serves the cause of humanity, instead of the other way around."

http://www.theglobeandmail.com/servlet/story/LAC.20060720.VETO20/TPStory/TPInternational/America/
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Kristina
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« Reply #2 on: July 30, 2007, 02:20:45 am »

There are three sources for stem cells:

   Adult stem cells are undifferentiated cells found throughout the body that divide to replenish dying cells and regenerate damaged tissues. Also known as somatic (from Greek Σωματικς, of the body) stem cells, they can be found in children, as well as adults.
   Embryonic stem cells are cultured cells obtained from the undifferentiated inner mass cells of an early stage human embryo (sometimes called a blastocyst, which is an embryo that is between 50 to 150 cells).
   Cord blood stem cells are derived from the blood of the placenta and umbilical cord after birth.


The other day, the Presiden't chief advisor, Karl Rove, suggested that all the same things could be done with adult stem cells as with embryonic stem cells. That idea is wrong:
quote:
________________________________________
Experts rip Rove stem cell remark
Researchers doubt value of adult cells

By Jeremy Manier and Judith Graham
Tribune staff reporters
Published July 19, 2006


When White House political adviser Karl Rove signaled last week that President Bush planned to veto the stem cell bill being considered by the Senate, the reasons he gave went beyond the president's moral qualms with research on human embryos.

In fact, Rove waded into deeply contentious scientific territory, telling the Denver Post's editorial board that researchers have found "far more promise from adult stem cells than from embryonic stem cells."

The administration's assessment of stem cell science has extra meaning in the wake of the Senate's 63-37 vote Tuesday to expand federal funding of embryonic stem cell research. The measure, which passed the House last year, will now head to Bush, who has vowed to veto it.

But Rove's negative appraisal of embryonic stem cell research--echoed by many opponents of funding for such research--is inaccurate, according to most stem cell research scientists, including a dozen contacted for this story.

The field of stem cell medicine is too young and unproven to make such judgments, experts say. Many of those researchers either specialize in adult stem cells or share Bush's moral reservations about embryonic stem cells.

"[Rove's] statement is just not true," said Dr. Michael Clarke, associate director of the stem cell institute at Stanford University, who in 2003 published the first study showing how adult stem cells replenish themselves.

If opponents of embryonic stem cell research object on moral grounds, "I'm willing to live with that," Clarke said, though he disagrees. But, he said, "I'm not willing to live with statements that are misleading."


Dr. Markus Grompe, director of the stem cell center at the Oregon Health and Science University, is a Catholic who objects to research involving the destruction of embryos and is seeking alternative ways of making stem cells. But Grompe said there is "no factual basis to compare the promise" of adult stem cells and cells taken from embryos.

Grompe said, "I think it's a problem when [opponents of embryonic research] make a scientific argument as opposed to stating the real reason they are opposed--which is [that] it's a moral, ethical problem."


Last week, the journal Science published a letter from three researchers criticizing the claim that adult stem cells are preferable to embryonic stem cells. The authors included Dr. Steven Teitelbaum of Washington University in St. Louis, who has used adult stem cells to treat bone diseases in children. The authors wrote that the exaggerated claims for adult stem cells "mislead laypeople and cruelly deceive patients."

The bill heading for Bush's desk would expand federal funding of work on stem cells taken from embryos. Such cells come from extra embryos originally created for in-vitro fertilization. Many experts believe embryonic stem cells could one day help regenerate damaged tissue for patients with conditions such as diabetes, spinal cord injury or Parkinson's disease, though embryonic cells have not yet been tested in humans.

Adult stem cells, which usually come from bone marrow transplants or umbilical cord blood, are widely considered less flexible than embryonic stem cells in forming many types of tissue. Yet adult stem cells already are in common use for certain conditions, such as replenishing immune cells after cancer treatment and treating some bone and blood disorders.


Bush allowed limited funding of embryonic stem cell work in August 2001, but he banned funding of cells taken from embryos after that date. However, private foundations and companies have continued to fund new embryonic research.

Many scientists and lawmakers argue that the federal funding limitation has hindered progress.

White House spokesman Ken Lisaius on Tuesday could not provide the name of a stem cell researcher who shares Rove's views on the superior promise of adult stem cells.

One of the only published scientists arguing that adult stem cells are better is David Prentice, a former professor of life sciences at Indiana State University and now a fellow at the Family Research Council, a conservative advocacy group.

The letter to Science last week was critical of a list Prentice compiled of 72 diseases that have been treated with adult stem cells.

Yet most of the treatments on the list "remain unproven," wrote Teitelbaum of Washington University and his co-authors, who claimed that Prentice "misrepresents existing adult stem cell treatments."

Prentice said in an interview that the Science authors "put words in our mouths"--he never claimed that the adult stem cell therapies were proven, only that they had benefited some patients. But he said some of his citations were unwarranted..

"We've cleaned up that list now," he said. Asked how the errors occurred, he said, "I think things just got stuck in."

One of the scientists on Prentice's list is Dr. Joanne Kurtzberg, a pediatric hematologist at Duke University Medical Center who has used umbilical cord blood to treat Tay-Sachs disease and other rare disorders. Kurtzberg said it's wrong to see stem cell science as a competition with only one winner.

"We don't know enough about the potential of either kind of cell," Kurtzberg said. "I don't think one type is going to be the answer to everything."

----------

jmanier@tribune.com

jegraham@tribune.com
________________________________________
http://www.chicagotribune.com/features/health/chi-0607190211jul19,1,5676240.story

With this issue, like so many others, the Bush Administration is lying about it.
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Kristina
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« Reply #3 on: July 30, 2007, 02:22:24 am »

Now then, how do we know just what stem cell research can do? Easy, there have already been some tests (successful ones) where the spinal chords of rats have been severed and then repaired and the rats have been able to walk around again, just like normal (though this has yet to be achieved in humans):



quote:
--------------------------------------------------------------------------------
Jell-O Fix for Spinal Cords


By Elizabeth Svoboda| Also by this reporter
02:00 AM Mar, 29, 2006


Stem cells embedded in futuristic materials may heal decades-old spinal cord injuries and rescue patients from paralysis, if recent experiments in rodents can be replicated in humans.

Stem cells have cured many rats of spinal cord injuries, but the treatment has yet to benefit humans. When it does, most scientists say the first treatments will benefit only the newly injured.

But Pavla Jendelova, a biologist at the Institute of Experimental Medicine in Prague, Czech Republic, found that adding stem cells to spinal implants made of hydrogels -- jelly-like polymers consisting of latticed networks of amino acids -- could build a bridge in spinal cords even with older injuries, and help patients to regain function.

"In chronic spinal cord injuries, there's a large cavity that develops over time in the injured area," she said. "We want to see if the hydrogels can breach this gap."


Hydrogels resemble the soft tissue that surrounds a human spinal cord as it develops in the womb, Jendelova said. Neurons grow through pores in the material, creating a scaffold that supports delicate cells. The pores are also large enough to allow the transmission of chemical signals that orchestrate neural development.

Jendelova believes hydrogels' physical properties, which are similar to those of Jell-O, increase the likelihood that stem cells will integrate successfully with existing spinal tissue.

"An ideal matrix for neurons would be soft, chemically inert and would have a high water content like a sponge -- something that resembles the natural environment around developing neural tissue," she said. Made of up to 99 percent water, hydrogels come closer to meeting these criteria than any other artificial material.

The Institute of Experimental Medicine team induced spinal cord lesions in 28 rats by removing small sections of the cord or compressing spinal cord tissue. They then filled the spinal cavity around the injured area with blocks of hydrogel laced with stem cells from rat bone marrow.

Four weeks later, the scientists analyzed the treated areas and found that the stem cells had successfully built new spinal cord tissue with nerve fibers that grew through the gaps in the hydrogel's amino-acid lattice. "We observed significant growth of neural tissue into the hydrogels," Jendelova said. "There were neurofilaments, axons and connective tissue growing into the whole area of the lesion."

Not only did the rats show unprecedented neural regrowth, they also recovered much of the limb function they had lost when the researchers initially injured them. Jendelova presented her findings last month at the Cambridge Healthtech Institute's molecular medicine conference in San Francisco.

"If you create a physical architecture, cells will often follow it," said Erin Lavik, a biomedical engineer at Yale University who is developing hydrogels that can be used as matrices to build blood vessel networks. The technique could prove crucial in tissue and spinal cord repair procedures.

Scientists have also tried nanofibers as frameworks for stem cell growth, according to Itzhak Fischer, a molecular neurobiologist at Drexel University who specializes in spinal cord repair. But because nanofibers are engineered to be strong and tough, they are less flexible and don't readily mold to a lesion.

--------------------------------------------------------------------------------

http://www.wired.com/news/technology/medtech/0,70513-0.html

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Kristina
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« Reply #4 on: July 30, 2007, 02:24:39 am »

The nervous system is not a particularly hospitable environment for nerve regeneration to begin with, Fischer said, "but if you can insert a scaffold that directs neural cells exactly where you want them, you're going to have a much better result."

For several years, Fischer has been investigating which hydrogel formulations best facilitate neural tissue growth. He is currently experimenting with "permissive peptides" -- protein strands attached to the gel's surface that attract newly developing nerve fibers.

In late 2004, Fischer and his colleagues implanted hydrogels drenched with a growth-factor compound similar to that secreted by stem cells into the severed spinal cords of 24 adult rats. The rats grew new, mature neurons, which are necessary for spinal cord development.

Despite his and Jendelova's early success, Fischer foresees future roadblocks. "It's tricky to make stem cells compatible with the nervous system environment," he said. Even if a hydrogel scaffold works beautifully, the body's immune system still might reject the foreign cells.

Like Fischer, Jendelova is cautious -- she estimates gel-based spinal cord repair clinical trials will begin within the next five years, but it's too soon to predict whether the treatment will translate into humans.

"The problem with transferring results from rodents to humans is that there are so many size differences," she said. "The hydrogels may be fine for a rat's small spinal cord, but we can't say whether they will work as well in a human one, which is more than 10 times thicker." Recently, however, she conducted hydrogel experiments in five pigs with injured spinal cords. The results suggest the gel implants may scale up better than she expected.

Several other stem cell-based techniques have cured rats of paralysis, but scientists have yet to try the techniques in humans. Hans Keirstead, an assistant professor of anatomy and neurobiology at the Reeve-Irvine Research Center, is one of them. His work is funded by Geron, and the company's chief scientific officer, Tom Okarma, said his scientists could begin human clinical trials using Keirstead's technique in 2007 -- but the first study will focus on newly injured patients.

Evan Snyder has also restored movement to previously paralyzed rats using a stem cell therapy.

Ultimately, according to Aileen Anderson, a neurobiologist at the University of California at Irvine, hydrogels could emerge as front-runners among the many stem cell-based spinal cord repair strategies being developed.

"There have certainly been experiments showing that you don't have to have a hydrogel scaffold to achieve some spinal cord regeneration," she said. "But they might be really useful in certain situations -- especially in injuries where the spinal cord is completely cut in two, and the scaffold forms a bridge between the sections."

http://www.wired.com/news/technology/medtech/0,70513-1.html?tw=wn_story_page_next1
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Kristina
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« Reply #5 on: July 30, 2007, 02:25:48 am »

Imagine the possibilities. Chris Reeve would have been able to walk again. Anyone suffering a spinal chord injury, in a wheelchair would be able to live their wildest dreams: get up and walk again. Most life-threatening diseases are caused by cell tissue damaged in some way. Stem cells could replace all of them. It's still years off from making the research work in humans, and that is why it is so vital that the work begin now.

And that is why it is so sad for all the people suffering now that we have a President still stuck in the Dark Ages in this, perhaps the most anti-science administration we have ever seen.

I would like to devote this thread to the science behind stem cell research so that people can see for themselves what it can do, however, I will leave this one political message: if there was a Democratic President or even enough Democrats in Congress to override the President's veto, this would have passed yesterday. It will pass eventually, it's just a matter of time. I hope that all the people suffering right now still have that time.
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« Reply #6 on: July 30, 2007, 02:26:40 am »

A petition to get the government to support stem cell research:

http://www.tomharkin.com/petition/stemcellcampaign.asp
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« Reply #7 on: July 30, 2007, 02:27:53 am »

New method makes embryo-safe stem cells
By MATT CRENSON, AP National Writer
Wed Aug 23, 10:57 PM ET



NEW YORK - In an innovative move, a biotech company has found a new way of making stem cells without destroying embryos, touting it as a way to defuse one of the country's fiercest political and ethical debates.


Some opponents of the research said the method still doesn't satisfy their objections and many stem cell scientists and their supporters called it inefficient and politically wrong-headed.

But a spokeswoman for President Bush, who vetoed legislation last month that would have allowed federal funding for embryonic stem cell research, called it a step in the right direction.

And Dr. Robert Lanza, an executive with Advanced Cell Technology, which created the new stem cell lines, said: "This will make it far more difficult to oppose this research."

Stem cells have become a Holy Grail for advocates of patients with a wide variety of illnesses because of the cells' potential to transform into any type of human tissue, perhaps leading to new treatments. But the Vatican, President Bush and others have argued that the promise of stem cells should not be realized at the expense of human life, even in its most nascent stages.

The new method works by taking an embryo at a very early stage of development and removing a single cell, which can be coaxed into spawning an embryonic stem cell line. With only one cell removed, the rest of the embryo retains its full potential for development.

The method was described online Wednesday in the British journal Nature. The journal published a similar paper by Advanced Cell Technology last year demonstrating the technique's viability in mice.

"The science is interesting and important," said John Harris, a professor of bioethics at the University of Manchester in Great Britain, commenting on the biotech company's efforts.

But few believe it will resolve the bitter ethical battle over stem cell research.

"This will please no one," predicted a longtime critic of the company, Glenn McGee, director of the Alden March Bioethics Institute in Albany, N.Y.

Some stem cell researchers complain that the new approach, though it may hold future promise, simply isn't as efficient as their current method of creating stem cells. That procedure involves the destruction of embryos after about five days of development, when they consist of about 100 cells.

Meanwhile, hard-line opponents of stem cell science argue that the technique solves nothing, because even the single cell removed by the new approach could theoretically grow into a full-fledged human. Some also object over the possibility the procedure could harm the embryo in an unknown way.

The method "raises more ethical questions than it answers," said Richard Doerflinger of the U.S. Conference of Catholic Bishops.

U.S. law currently bans federal funding of any research that harms human embryos. A White House spokeswoman said the method's eligibility for funding could not yet be determined, "but it is encouraging to see scientists at least making serious efforts to move away from research that involves the destruction of embryos."

President Bush has said that he personally opposes any research that sacrifices embryonic life, even to save an existing person. In August 2001 the president limited federal funding to research on a few dozen stem cell lines that had been created up to that point.

Scientists complain that the decree has severely crippled progress in the field. But recent developments have moved them toward their twin goals of attracting non-federal money for stem cell research and overturning the restrictions.

Several states, including California, New Jersey and Illinois, have set up ways to fund the research. A number of Democratic candidates in this year's congressional elections are focusing on the issue.

The research at Advanced Cell Technology subverts those efforts, McGee said. But writing in Nature earlier this year about the demonstration of the technique in mice, Stanford University stem cell researcher Irving Weissman disagreed.

"Although the efforts cited here will be criticized as a diversion of good science by politics, I believe all of these attempts to advance and translate medical science should be pursued in parallel," Weissman wrote.

Scientists at Advanced Cell, based in Alameda, Calif., devised a clever means of piggybacking on existing fertility treatments to avoid the creation, manipulation or destruction of embryos specifically for the production of stem cells. The fertility procedure, known as preimplantation genetic diagnosis, or PGD, is used when parents want to avoid having a child with a lethal or severely debilitating birth defect. About 1,000 such procedures are performed each year in the United States.

PGD begins with in vitro fertilization to produce numerous embryos. At a very early stage of development, when the embryos are no more than a ball of eight to 10 cells, a technician extracts a single cell from each one. The extracted cells are tested for genetic disorders, and those free of defect are then implanted in the mother in the hope they will develop.

The new stem cell production method takes a cell extracted during PGD and allows it to divide. One of the two resulting cells is genetically tested as in normal PGD; the other is cultured to encourage the development of stem cells.

"It's nothing revolutionary," said Yury Verlinsky, a Chicago geneticist who specializes in PGD.

Though the new procedure may satisfy the president's objections to stem cell research, it does not meet the ethical standards of the Roman Catholic church, which opposes both PGD and in vitro fertilization.

Advanced Cell Technology was able to produce two viable stem cell lines from a total of 16 embryos. The lines appeared to exhibit the full potential of embryonic stem cells to develop into any type of human tissue, the researchers reported, but additional study is needed to verify that.

"I think this will become a standard way of producing stem cell lines," said Ronald M. Green, a Dartmouth College professor of religion who is an unpaid bioethics adviser to Advanced Cell Technology.

The company, which has been struggling financially, owns about 300 patents that it hopes to develop into medical treatments. After news of its announcement broke on Wednesday, the price of its over-the-counter stock shot up from 42 cents to close at $1.83 per share.

http://news.yahoo.com/s/ap/stem_cells
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« Reply #8 on: July 30, 2007, 02:28:47 am »

Mass. governor says stem-cell research "Orwellian" Fri Sep 1, 12:10 PM ET

BOSTON (Reuters) - Massachusetts Gov. Mitt Romney, a 2008 Republican presidential hopeful, said on Thursday his administration's new restrictions on stem cell research are aimed at heading off an "Orwellian" future.


The state's Department of Public Health this week issued regulations banning the creation of embryos for research purposes. Scientists say stem cell research could lead to breakthroughs in treatments for diseases including cancer. But the issue has become ethically and politically volatile because extracting the cells entails destruction of an embryo.

"I believe it crosses a very bright moral line to take sperm and eggs in the laboratory and start creating human life," Romney told reporters. "It is Orwellian in its scope. In laboratories you could have trays of new embryos being created."

Romney spoke a week after a Massachusetts company, Advanced Cell Technology, said it had developed a way to make human embryonic stem cells without harming the original embryo, a finding it said could dispel ethical objections.

Stem cells are the body's master cells, capable of turning into any other type of cell. They are available from many sources, but experts believe the most powerful and versatile cells may be those taken from days-old embryos.

President Bush last month vetoed a bill that would have raised federal funding for research using embryonic stem cells, which he views as the destruction of life.

Romney appears to be positioning himself for the 2008 Republican primaries, when he will need to win over conservative voters to get the party's nomination, said Julian Zelizer, a Boston University history professor who follows Romney closely.

"Stem cells are like the new abortion, in that it's become a litmus test for conservatives nationally," Zelizer said. Massachusetts legislators opposed Romney's move, noting that in May 2005 they enacted a law over Romney's veto allowing stem cell research to take place in the state.

At that time Romney offered an amendment that would have banned the creation of embryos for research purpose. "The legislature debated, and soundly defeated, the exact language the Department (of Public Health) has adopted as a regulation," wrote State Rep. Daniel Bosley, a Democrat, a memo to fellow legislators. "Consequently, we should oppose this language."

http://news.yahoo.com/s/nm/20060901/hl_nm/stemcell_research_dc

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« Reply #9 on: July 30, 2007, 02:30:00 am »

Scientists hail a stem cell experiment
Research is seen helping in studies of birth defects
By Raja Mishra, Globe Staff | December 11, 2003


Harvard-affiliated researchers fertilized mouse eggs with sperm grown from embryonic stem cells, according to a new study with broad implications for understanding infertility and birth defects.

In the same study, the researchers created a continuously regenerating pool of embryonic germ cells, early-stage cells that go on to become sperm and eggs. Scientists suspect many birth defects originate in these early cells. But they can only be harvested from aborted fetuses, and thus have not been widely studied. The new study shows how to grow them from stem cells in a petri dish.

"Germ cells are given the responsibility for perpetuating the species, and understanding how germ-cell formation goes awry may teach us about early developmental defects, as well as some forms of male infertility," said Dr. George Q. Daley of Children's Hospital and Harvard Medical School, the study's senior author. "Our research is aimed at understanding normal and pathologic tissue formation, and not so much at futuristic means of assisted reproduction."

The study, which appeared yesterday in the online version of the journal Nature, gives scientists powerful new tools to study the initial stages of life, when tiny multicell embryos quickly become complex creatures with a wide variety of tissues. Genetic errors in this period may account for numerous afflictions after birth. But because the time frame involved is fleeting and controversial ethical issues are involved, work has moved slowly.

"This study may eliminate the need to generate germ cells from aborted fetuses," sad Daley, whose study did not involve any human cells.

Embryonic germ cells are rare yet crucial to life. About 50 of the cells appear briefly during the first weeks of pregnancy. They quickly turn into sperm in males and eggs in females. They are ultimately responsible for passing down genes to offspring.

These embryonic germ cells develop alongside embryonic stem cells, the source of much recent controversy. Stem cells go on to form every tissue in the body. Scientists want to use them to develop replacement tissues to treat diseases like diabetes and spinal injuries. Opponents argue the embryo destruction necessary to get them is immoral.

Daley's team plucked germ cells out of mouse embryos less than 10 days old. Then, in a petri dish, they added nutrients that kept the germ cells regenerating rather than evolving into sperm or eggs. In some sense, these germ cells are immortal: they carry on a parent's entire genetic legacy to the next generation. Most other cells in the body become very narrow and specific in function, as various genes turn off and on. Then, they die.

Germ cells' immortality may point to ways to control another immortal cell type, the cancer cell. And their role in the reproductive process might shed light on birth defects that occur very early after fertilization.

After the researchers attained this goal, they decided to push on.

"We said, well, jeepers, if we have germ cells we should see if they can develop into sperm or egg cells," said Daley.

They grew some of the germ cells into sperm. However, the sperm did not develop completely, lacking tails, which normal sperm use to swim their way to eggs. The researchers injected the tail-less sperm into mice eggs, successfully fertilizing them. The lab will soon implant the eggs into mice.

"We will see if they make pups," said Niels Geijsen, lead author of the study and a principal investigator at the Center for Regenerative Medicine and Technology at Massachusetts General Hospital. This process may offer insights into infertility. Researchers suspect many cases originate in the transition from germ cell to sperm cell.

Japanese researchers announced in September that they, too, had created sperm from stem cells. But stem cell specialist Hans R. Schoeler of the University of Pennsylvania said the Japanese study was conducted largely inside living mice, something he called cumbersome and labor-intensive.

"But here we have the example where everything has been done in the dish and you can really study it in this way because it's right in front of you," he said.

Material from the Associated Press was used in this report. Raja Mishra can be reached at rmishra@globe.com.

Copyright 2006 Globe Newspaper Company.

http://www.boston.com/news/nation/articles/2003/12/11/scientists_hail_a_stem_cell_experiment/
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« Reply #10 on: July 30, 2007, 02:31:16 am »

Foes of stem-cell research create their own scientific reality

The Stowers Institute for Medical Research has spoken. If Missouri bans embryonic stem-cell research, as some legislators want, the institute will not build a second facility in Kansas City. Is that understood?

California needs no such warnings. Not only does the state allow this research, but it may soon raise $3 billion of its own money to pay for it. New Jersey, meanwhile, plans to spend $6.5 million on a stem-cell-research facility.

All these things are happening at the state level because President Bush has refused to commit the federal government to advancing the study of embryonic stem cells. The research could find cures for Alzheimer's, Parkinson's, diabetes and other diseases. Polls show a public solidly for it. But anti-abortion groups object to the research because it destroys embryos, and Bush wants the groups' support.

So rather than ban embryonic stem-cell research in an honest and straightforward manner, Bush has created confusion and a pretend compromise. His famous executive order of three years ago allowed funding for research only on the 79 embryonic stem-cell lines existing on Aug. 9, 2001 58 of which were useless.

And he was willing to spend a big $25 million a year on it. That number must have Californians rolling with laughter as they prepare to approve a bond issue allocating eight times as much each year for 10 years.

If Bush believes destroying embryos is immoral, why does he support any research on embryonic stem cells at all? And why doesn't he ban the practice of in vitro fertilization, which creates embryos that get thrown out? And, finally, what's so magical about the date Aug. 9, 2001?

Opponents of embryonic stem-cell research must contend with polls showing that 73 percent of the public supports it. So they have created their own scientific reality. They drag in scientists who claim that adult stem cells, taken from bone marrow or umbilical cords, can also produce cures no need to destroy embryos.

Serious biologists say that's nonsense. Adult stem cells may have their uses, but only the embryonic stem cells can divide and produce new cells for replacing tissue. Really, if the nation's biotech centers thought adult stem cells would do the trick, would they be out fighting the religious right over the use of embryos?

Meanwhile, first lady Laura Bush has been sent out to throw cold water on the hopes for embryonic stem-cell research and also drum up some resentment against its backers. "My dad died of Alzheimer's," she said recently. "And to hear people say that cures are right at our fingertips it's just not right."

What's not right is to deprive Americans of reasonable hope for a medical breakthrough, even if it takes 10 or 20 years. There's something else Laura Bush doesn't get: For people who have lost a loved one to an awful disease, the fight is not over. Many dedicate themselves to helping find a cure for the disease that caused such suffering often as a tribute to the one who died. Laura Bush needs a long talk with former first lady Nancy Reagan, who is pushing for embryonic stem-cell research. The death of Nancy's husband, Ronald Reagan, from the ravages of Alzheimer's has not dimmed her desire for a cure.

Of course, the Californians supporting the bond issue expect rewards beyond the joy of finding miracle cures. The $3 billion would stay in the state as a giant welcome mat for biotech companies. If you were a big company looking for a place to put your biotech research park, where would you rather go: to Missouri, where lawmakers want to make your life's work into a felony? Or to California, where the state is strewing dollars in your path?

While a few states struggle to move forward, Bush seems content to let American medical research fall into decline. John Kerry says he would not stand by as the states and private philanthropy go it alone against Britain, South Korea and other biotech powers.

But even if Bush wins in November, the more enlightened states have their Plan B: to groom themselves as American refuges for 21st-century science. The others will become backwaters. And it will be up to Missouri to decide what kind of state it wants to be.

Providence Journal columnist Froma Harrop's column appears regularly on editorial pages of The Times. Her e-mail address is fharrop@projo.com


Copyright 2004, The Providence Journal Co.

http://seattletimes.nwsource.com/html/opinion/2002043479_harrop23.html
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« Reply #11 on: July 30, 2007, 02:32:55 am »

Stem cells fill in for liver in mouse experiment Sun Nov 5, 4:42 PM ET


WASHINGTON (Reuters) - Stem cells grown from mouse embryos helped power a liver replacement device, Japanese and U.S. researchers reported on Sunday.


Their experiment suggests another use for the cells, controversial when taken from human embryos. They used the cells in a bioartificial liver, an implanted device that uses liver cells to replace some liver function.

Writing in the journal Nature Biotechnology, Ira Fox of the University of Nebraska Medical Center, Naoya Kobayashi of Okayama University in Japan and others said their cells saved the lives of mice that otherwise would have died of liver failure.

"Use of this device in mice with acute liver failure, which uniformly die within 4 days of inducing hepatic (liver) failure, resulted in 90 percent long-term animal survival," they wrote.

Stem cells are the body's master cells, and those taken from days-old embryos have the power to transform into any kind of cell or tissue in the body.

But the use of human embryonic stem cells is controversial, with some conservatives, including President George W. Bush, opposing their use on moral grounds.

Proponents say stem cells taken from a variety of sources could transform medicine, offering ways to understand disease and replace damaged organs and tissues.

Liver failure can be caused by viruses such as hepatitis, by drug or alcohol damage and by a range of other diseases. Often the only cure is a transplant, and more than 5,000 liver transplants are done in the United States each year.

More than 17,000 Americans are on the waiting list for a new liver.

"Treatment could be improved by bioartificial liver support, but this approach is hindered by a shortage of human hepatocytes (liver cells)," the researchers wrote.

The researchers grew mouse embryonic stem cells and coaxed them into becoming liver cells. They caused liver failure in some lab mice and implanted the bioartificial livers, seeded with the newly grown liver stem cells.

The new cells "developed characteristics nearly identical to those of primary hepatocytes (liver cells)."

The new cells filtered the blood much as the liver does, and kept the mice alive, while mice not fitted with a device died within two days, the researchers wrote.
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« Reply #12 on: July 30, 2007, 02:34:09 am »

Stem cells help dogs with dystrophy
By MALCOLM RITTER, AP Science Writer



NEW YORK - In promising new research, stem cells worked remarkably well at easing symptoms of muscular dystrophy in dogs, an experiment that experts call a significant step toward treating people.


"It's a great breakthrough for all of us working on stem cells for muscular dystrophy," said researcher Johnny Huard of the University of Pittsburgh, who wasn't involved in the work.

Sharon Hesterlee, vice president of translational research at the Muscular Dystrophy Association, called the result one of the most exciting she's seen in her eight years with the organization. Her group helped pay for the work.

She stressed that it's not yet clear whether such a treatment would work in people, but said she had "cautious optimism" about it.

Two dogs that were severely disabled by the disease were able to walk faster and even jump after the treatments.

The study was published online Wednesday by the journal Nature. It used stem cells taken from the affected dogs or other dogs, rather than from embryos.
For human use, the idea of using such "adult" stem cells from humans would avoid the controversial method of destroying human embryos to obtain stem cells.

The Nature paper focuses on Duchenne muscular dystrophy, a muscle-wasting genetic disorder that occurs in about 1 in every 3,500 male births. It's the most severe and most common childhood form of muscular dystrophy and the best-known. In theory, the stem cell treatment might also help other muscle dystrophies or even age-related muscle wasting, Hesterlee said.

Children with the disorder have trouble walking as early as preschool, and nearly all of them lose their ability to walk between ages 7 and 12. Typically, they die in their 20s because of weakness in their heart and lung muscles. There is no known cure.

The dog study was done by Giulio Cossu, director of the stem cell institute at the San Raffaele Scientific Institute in Milan, Italy, with colleagues there and elsewhere.

"We do not know whether this will work in patients," Cossu said in a telephone interview. He said he hopes to start a small experiment in children in the next year or two.

The scientists worked with golden retrievers that suffer a crippling form of dystrophy very much like the human one. Researchers studied the effect of repeated injections into the bloodstream of a kind of stem cell extracted from blood vessel walls.

The best results appeared when the cells were taken from healthy dogs. But Cossu said scientists should pursue the possibility of genetically manipulating a patient's own cells and using them instead. That way, patients wouldn't have to undergo lifelong treatment to avoid rejection of donated cells.

In one of several experiments, three dogs that had not yet shown impairment in walking were injected five times, a month apart, with cells taken from other dogs.

One dog completely avoided symptoms and continued to walk well even five months after both the injections and the anti-rejection therapy were stopped.

A second dog also did well initially but died suddenly of a heart problem after just two months on the treatment. It's not clear whether the problem had anything to do with the treatment, or whether the initial good result would have continued, Cossu said.

The third dog showed partial protection, being able to walk and even run with a limp, but then progressively lost walking ability within a few days after the anti-rejection treatment was stopped.

The researchers also treated two dogs that were severely impaired by the disease. Both gained the ability to move much faster and to jump, and one was even able to run, although neither could use the hind legs normally.

One of these dogs rapidly lost walking ability when the anti-rejection treatment was stopped, but the other continued to walk well for five months until succumbing to pneumonia. That's a common fate for dogs with the genetic condition because of weakness in breathing muscles.

Cossu said he believed that a human treatment could be directed more at breathing muscles than it was in the dogs.

The cells helped strengthen muscle by fusing with regenerating muscle fibers and pumping out a protein that's missing in dogs with the disease.

___

On the Net:

Nature: http://www.nature.com/nature

Muscular Dystrophy Association: http://www.mda.org

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