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-- [ From: Seymour Gross * EMC.Ver #2.5.3 ] -- Philadelphia Inquirer, January 20, 1999, Page 1 U.S. to finance research on stem cells from embryos Promise is great, but ethics are an issue. ------------------------------------------------------------------------ -------- Researchers give nod to experimental diet drug HEALTH PHILADELPHIA: More health news and Q&A's with doctors ------------------------------------------------------------------------ -------- By Usha Lee McFarling INQUIRER WASHINGTON BUREAU WASHINGTON -- The federal government has decided to fund research on embryonic stem cells -- controversial biological entities that promise revolutionary medical advances like patching hearts, reversing paralysis , and curing such maladies as Parkinson's disease. A federal ban on all experiments that destroy human embryos does not apply to stem cells, because once they are taken from an embryo and cultivated in a laboratory dish, the cells can no longer develop into a whole organism, said Dr. Harold Varmus, director of the National Institutes of Health. The decision, which some see as an ethical stamp of approval, marks an important turn in a debate over the newly discovered cells. While researchers who finally captured and tamed the elusive cells this winter certainly pushed back a biological barrier, they are still confronting an ethical one. For instance, scientists have yet to agree on exactly what these new cells represent -- if they are closer to embryos and merit moral consideration, or if they are more like basic cells that can be casually discarded. The debate is rife with larger questions: Should scientists use "spare embryos" from infertility clinics for work that could benefit millions? Should the moral arguments surrounding abortion make fetal tissue off- limits as a source of stem cells? And might a clump of stem cells have independent "moral status"? "Biology is changing the way we think about each cell in our body," said Varmus. "Our perspective on life has been changed profoundly by these developments." Varmus made his comments yesterday before the National Bioethics Advisory Commission, which met in Washington to address the ethics of stem-cell research at the request of President Clinton. While federally funded researchers may work on cells that have already been cultivated by scientists working with private funds, they are not permitted to use federal dollars to obtain new cells by destroying living embryos or creating human clones, Varmus said. Work on obtaining cells from the tissue of aborted fetuses could be funded because it does not involve destroying an embryo, he said. Varmus said his decision was based on a legal ruling by lawyers at the Department of Health and Human Services, which would fund any such research. He said no federally funded research would be allowed until ethical guidelines were in place and the issue had been discussed with Congress and the public. He estimated that stem cell research could account for up to several million dollars' worth of the NIH's $16 billion budget. Sen. Arlen Specter (R., Pa.) has said he is also drafting legislation that would ensure that bans on embryo research do not impede stem-cell research. "I think every day that we lose on lifting the NIH ban costs lives," he said last week during a Senate subcommittee hearing on stem cells. Disagreement over the decision was already surfacing yesterday from those who oppose any research linked to the destruction of embryos. "The method of obtaining the cells is lethal to the embryo," said Richard M. Doerflinger of the National Conference of Catholic Bishops. "The fact that NIH will not fund the act of destruction itself seems secondary. It will reward those who use the fruits of that destruction." Others argued that any decisions on the ethics of the research must take into account possible medical benefits. "The potential of this area makes it unthinkable not to proceed," said Austin Smith, a leading stem-cell researcher from Edinburgh, Scotland. Doerflinger said that scientists should pursue other ways to obtain stem cells, such as obtaining tissue from miscarriages, and that no matter what the medical benefits are, "the ends do not justify the means." New scientific developments in the rapidly moving field have some scientists hoping for a way to harness the power of stem cells that avoids using controversial embryonic tissue. This month, Swedish scientists reported finding neural stem cells in the brains of adult mice. The cells might be raw material to create new neurons for people with spinal cord injuries or Parkinson's or Alzheimer's disease. Using cells from adult human brains would sidestep ethical issues, but it is unclear whether the neural stem cells could be converted into other, non-brain tissues. Varmus said it might be possible to reengineer a patient's own adult cells back into stem cells and use those to create various types of new tissues. Human embryonic stem cells made their long-awaited debut in November, when James Thompson, a developmental biologist from the University of Wisconsin, published a paper describing how he had isolated the elusive and finicky cells from extra embryos that had been donated by infertility clinic patrons and coaxed them to grow in his laboratory dishes. Days later, John Gearhart of Johns Hopkins University reported that his lab had accomplished the same feat using tissue from fetuses that had been aborted. Embryonic stem cells are difficult to capture because they are so fleeting. In the elegant choreography that transforms a single cell into a human baby, cells leap quickly down paths of individual and irreversible development: Some are destined to become heart, some muscle and others brain. But if captured early enough, the cells can turn themselves into virtually any one of the body's 210 cell types. Corralling the cells offers the potential to create tissues-to-order -- new nerve cells or new heart muscle -- a veritable spare-parts kit for the human body. The cells could also be used to create batches of living human tissue, now a rare and costly commodity, in which to screen new drugs. That potential will not be turned into therapy until scientists overcome two major obstacles. The first is finding ways to keep stem-cell transplants from being rejected by a recipient's immune system. This might require genetically engineering the cells so they aren't recognized as foreign, or using cloning techniques so cells match a donor exactly. Second, scientists will not be able to create a catalog of tissues until they unravel the chemical cocktails that swirl inside and outside stem cells and goad them into becoming different types of tissue. Breaking those codes will require much work at the laboratory benches of numerous scientific teams. "The challenge that's facing us is to make this real," said Smith, the researcher. "How long will this take?" Those in the field estimate that it will be five to 12 years before any of the new stem-cell findings are converted into medical therapies. That timetable would be speeded by federal funding, which is likely to attract more scientists to the field. Proponents also say federal funding would offer more ethical oversight and academic openness than research conducted in private, for-profit laboratories. The current research, all legal, was funded privately by Geron Corp., a Silicon Valley biotechnology company. The company's stock nearly doubled after the stem-cell research was announced in November. © 1998 Philadelphia Newspapers Inc.