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Stem Cells: Hope and Controversy on the Bio-Tech Frontier New research on stem cells might lead to cures for diabetes, Parkinson's and Alzheimer's, and to growing replacement organs from a patient's own tissue. Start Date: 1/25/99 The biotech world is buzzing with news about stem cells. Recent scientific research indicates that these cells, which develop early in the life of an embryo and then differentiate into all kinds of specific tissue, might provide the means to cure a host of ravaging diseases from diabetes to Parkinson's to Alzheimer's. There are even indications that stem cell research could lead to growing new organs from a patient's own tissue, allowing virtually unlimited "replacement parts" to be transplanted without threat of rejection. "In fact, the list of possible therapeutic uses is almost endless," says Lawrence Goldstein, a professor of pharmacology at the University of San Diego School of Medicine. Controversy over human stem cell research has focused on the main source of such cells: embryos. Stem cells can be isolated from aborted fetuses, from unused embryos created in-vitro, or from cloning. All the ethical issues associated with abortion and human cloning thus come to bear upon those who advocate aggressive research on stem cells. A number of leading U.S. legislators have argued strongly that a way must be found to allow such research to go forward with federal support. In recent Congressional hearings, Goldstein and others testified that, if stem cell research were conducted only with private or corporate funds, the valuable results might be tied up in patents and proprietary contracts that could restrict access not only for further medical research but also to patients. At issue is a federal ban on funding research involving the creation, manipulation or killing of human embryos. Senator Arlen Specter (R, Pennsylvania), chairman of the hearings, said, "My hope is that we might move legislation to lift the ban at a very early stage... Many people have the idea that using human embryos destroys lives. We have to disabuse them of this notion." Senator Tom Harkin (D, Iowa) agreed, saying that he was persuaded that embryonic material discarded from abortion clinics did not have the potential to grow a living human being and therefore could be exempted from the ban. "It seems obvious to me and to every scientist testifying here last month that this research can be federally funded," he said. The latest development in this controversy, announced on January 19, 1999 by the National Institutes of Health (NIH), is a somewhat tortured ruling that federal funds may be used in stem cell research as long as such funds are not used to actually grow stem cells from embryonic tissue. This means, in effect, that researchers working under federal grants must acquire stem cells from privately funded sources. Meanwhile, the private sector is moving swiftly forward in this arena. A leader in the field, Geron Corporation of Menlo Park, California, is negotiating with dozens of potential collaborators, notably Dr. Ian Wilmut of Scotland's Roslin Institute, who successfully cloned the famous sheep Dolly. Geron's publicly traded stock has gone up significantly since they announced recent breakthroughs in stem cell research. In the longer run, however, the controversy over embryos could be sidestepped altogether. According to Angelo L. Vescovi, of the National Neurological Institute in Milan, Italy, it may be possible to isolate stem cells from the tissue of an adult patient, then grow new tissue, even whole organs, from them. Vescovi headed a team that recently succeeded in isolating stem cells from the brain tissue of an adult mouse, then caused those stem cells to become blood-creating cells. Though Vescovi acknowledges that there is a huge gap between one experiment with a mouse and successful procedures in humans, his research is undeniably promising. "You may be able to use your own stem cells to make new tissue," he says. "As a concept, I don't see any problem in adult stem cells being used to make new skin, for instance." Even that one application, if successfully developed, could revolutionize the medical treatment of any condition that currently depends upon skin grafts, such as major burn trauma or cosmetic birth defects. But innumerable other applications are also imagined, if the research lives up to its promise. Vescovi's work, which was reported in the journal Science on January 21, 1999, shows that "mature stem cells are a lot more plastic than we imagined ... they can produce a lot more cell types than was previously thought," said Christopher Bjornson, a researcher at the University of Washington and a member of Vescovi's team.
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