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While politicians debate the ethics of embryonic stem cell research,
While politicians debate the ethics of embryonic stem cell research,
scientists at UW and elsewhere push the envelope with more breakthroughs By MARILYNN MARCHIONE of the Journal Sentinel staff Last Updated: July 29, 2001 Medical Science Photo/Jeff Miller, UW-Madison Great promise, great concern: Culture trays containing human embryonic stem cells are studied in developmental biologist James Thomson's research lab. Photo/Jeff Miller, UW-Madison All-purpose cells: Microscopic views show human embryonic stem cell colonies in different stages of development. The stem cells sometimes include a core of undifferentiated cells surrounded by a margin of differentiated cells, such as the small colony at right in Figure B. The Stem Cell Process Related Coverage Funding ban: Complicates life for researchers Delegation: Divided on stem cell research Quotable The decision will be made. I doubt it will be quickly. . . . We've committed to continuing regardless of what the decision is. - James Thomson, stem cell discoverer Coming Monday The state's biotechnology industry is working harder than ever - not just in the labs, but also in the political arena, where it hopes to head off restrictions on research. Madison - While politicians debate whether to let tax money be used for embryonic stem cell research, scientists are advancing it in ways that significantly raise the stakes. "We're not waiting," said the cells' discoverer, James Thomson of the University of Wisconsin-Madison. Thomson has quietly started from scratch to grow new embryonic stem cells - the body's most primitive and universal building blocks - that would comply with existing federal funding rules in case President Bush lets them stand. None of the current cells would qualify. Another UW scientist has taken Thomson's cells and grown blood "master cells" from them - an extraordinary, soon-to-be-published feat that some experts say might one day provide a cure for leukemias and other cancers as well as safer blood for transfusions, free of health threats such as viruses and mad cow disease. A third UW researcher has grown clumps of human nerve cells, a hoped-for treatment for spinal cord injuries and neurological diseases, and a fourth just made a key discovery toward growing cells that would make insulin, a potential treatment or cure for diabetes. Both just submitted their work to medical journals. Meanwhile, at Johns Hopkins University in Baltimore, researchers led by John Gearhart are helping paralyzed mice walk by giving them primitive, stemlike cells from aborted human fetuses. Fetal cell research has long been eligible for federal funding; abortion opponents have been unable to block that work. In the private business world, scientists recently announced some very controversial experiments: A Virginia infertility clinic made embryos just to do medical research on them, and a Massachusetts firm started trying to clone embryos to collect their stem cells. In some respects, the science is advancing at a dizzying pace. In others, it is moving agonizingly slowly, hurt by a lack of resources. "There are a lot of things we'd like to do but can't," said Jon Odorico, an assistant professor of surgery at UW who is working on the insulin-producing pancreatic cells. Only two applications were received by the March 15 deadline that the National Institutes of Health had set for the first round of grants for embryonic stem cell research, a process Bush stopped until he decides whether the work should be publicly funded at all. "The decision will be made," Thomson said. "I doubt it will be quickly. It could be tomorrow or it could be six months from now. We've committed to continuing regardless of what the decision is." Bush's decision will be one step in a long process, Thomson noted. Congress may intervene, and lawsuits inevitably will be filed by whatever side loses. Two suits already have been filed, one by Thomson and other researchers. The final word may be years away. In Thomson's view, stem cells represent the discovery of a lifetime. He compares it with polymerase chain reaction or PCR, a way to amplify DNA that made genetic research possible and affected everything from crime investigations to testing for diseases. "PCR revolutionized biology, and embryonic stem cells are going to do the same thing," Thomson said. "They're going to be used for a whole host of things we can't predict right now." The scientific community stands solidly behind him on that point. In February, 80 Nobel Prize winners wrote a letter urging federal funding. The heads of dozens of universities and academic medical research centers did the same, and a recent report by NIH scientists concluded that embryonic stem cells have unique potential for treating diseases and unraveling basic biological mysteries. But anti-abortion activists, Roman Catholics and many others oppose the research because an embryo must be destroyed to get the stem cells. Between the proponents and opponents are people who hope that some compromise can be found to allow promising areas of science to move forward in a limited and ethically controlled way. In the meantime, without federal funds for their work, Thomson and about a dozen others at UW are continuing embryonic stem cell research at two privately funded labs with money from the Wisconsin Alumni Research Foundation, other foundations, biotech firms, disease advocacy groups and drug companies. Blood 'master cells' The most stunning recent development has been UW scientist Dan Kaufman's work to grow from Thomson's embryonic cells hundreds of colonies of blood "master cells," which then formed red blood cells, clotting factors called platelets and other blood cell types. Isolating the blood master cell, called the adult hematopoietic stem cell, and getting it to grow and multiply in a lab dish has been the ultimate quest in hematology, said Richard Aster, a Medical College of Wisconsin professor and former president of the Blood Center of Southeastern Wisconsin who's nationally known for his pioneering work on platelets. "It's something people have been trying to do for a long, long time, the Holy Grail in this kind of work," he said. The hematopoietic stem cell is what's actually being given when patients have bone marrow transplants to try to cure cancer or replenish immune systems destroyed by cancer treatment. But scientists have never been able to isolate that cell from marrow or circulating blood. Because they can't, when they do a transplant, they remove all of a donor's white blood cells, knowing that the stem cells are somewhere in the mix. "There are very few of them, to be sure, maybe one in 1,000 (cells) at best," Aster said. That leads to the second problem - trying to multiply those scarce adult stem cells into enough to treat a cancer patient. Even when researchers establish colonies containing such cells, it's not possible to expand them without the cells losing their "stemness." "They immediately differentiate. It's like trying to catch a greased pig. They won't sit still," Aster said. If Kaufman has gotten blood master cells from embryonic stem cells and multiplied them in the lab, "that would remove a huge obstacle" to treating diseases, especially for the three out of four people who can't have marrow transplants because they lack a matched donor, Aster said. "That's exciting if that's true," he said of what Kaufman reportedly has achieved. Blood grown from embryonic stem cells could have other big uses. "This could potentially be used to make cells that could be transfused, and you would not have to worry about viruses," Kaufman said. "Theoretically, there is no limit to the number of cells you could produce." Aster doubted that Kaufman's work would replace donated blood for transfusions, saying the growth factors and culture media needed to make the blood cells are so expensive that it probably wouldn't be worth it except for rare blood types. "This isn't going to happen for another hundred years, that people would actually make blood for transfusions that way," Aster said. Thomson disagreed. "Just because the growth factors now cost $200 for a tiny vial doesn't mean they always will," he said, pointing out past examples where such things became cheaper once they were commercialized and mass-produced in industrial settings. Other research Other promising work is being done by Su Chun Zhang, a UW scientist who has taken Thomson's embryonic stem cells and grown them into colonies of neural cells. He can't direct the cells to form specific nerves yet but is working on that next, Thomson said. Odorico, an assistant professor of surgery, has a $500,000 grant from the Juvenile Diabetes Research Foundation to try to grow the kind of pancreatic cells that are damaged by diabetes. He started that work in January and recently made a key discovery on the genetics of how embryonic stem cells can be made to turn into cells that produce insulin. All this work involves differentiation, or getting the embryonic stem cells to turn into specific kinds of cells and tissues. Thomson is involved in remaking the embryonic cells themselves. When he first isolated such cells in 1998, it was before the NIH published rules for funding such research. His cells now conflict with the rules on two points. The first is a wording issue with the embryo donation consent form that is more style than substance but still an obstacle. The bigger problem is that the NIH rules say the cells have to have been derived from frozen embryos. Thomson used fresh and frozen. Ironically, the very steps he used to ensure the anonymity of the embryos he was working with now prevent him from separating donated embryos that came from Israel, which were frozen, from those that came from the UW infertility clinic, which were a mix of fresh and frozen. "I have in my notebook I got five embryos today," but not which came from where, he said. "We pretty much do know which ones are fresh (and which are) frozen, but we can't document it in a satisfactory way." So he started over last fall. The new consent forms and experimental procedures were just approved by the UW committee that oversees human research. "If we got the appropriate (embryo) donations today, it would take six months" to establish a self-perpetuating colony of stem cells, Thomson said. "What I'm worried about is Washington will change (the rules) and our new cell lines won't qualify," he confessed. That would send him back to the lab, to start all over yet again. Appeared in the Milwaukee Journal Sentinel on July 29, 2001. __________________________________________________ __ Maksim (Max) Bily mail to : imax@odyssee.net ---------------------------------------------------------------------------- --------------- Visit http://carecure.rutgers.edu/spinewire/index.html for best sci research info on Web www.thinkwave.com -Where Teachers, Students and Parents Communicate Play International Red Cross Lottery online for weekly jackpot of 20.000.000 Swiss Franks tax free... http://www.pluslotto.com/default.asp...=3300003298889
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