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New Potential for Stem Cells Suggested Findings of Three Studies May Affect Treatment of Diabetes, Alzheimer's Disease By Rick Weiss - Washington Post Staff Writer Friday, April 27, 2001; Page A02 Three research reports provide evidence that cells from human embryos and fetuses have the potential to cure ailments affecting millions of Americans -- a conclusion that is likely to intensify an already heated debate over the ethics of human embryo cell research. In one report, old rats performed better on a test of memory and learning after scientists injected brain cells from aborted human fetuses into the rodents' age-addled brains. It's the first indication that such transplants can prompt cognitive improvements, and it hints at a treatment for Alzheimer's disease and other forms of dementia. In a second report, scientists coaxed embryo cells in laboratory dishes to become the specialized parts of the pancreas responsible for regulating blood sugar levels -- an advance that could lead to an effective treatment for many of the nation's 16 million diabetics. A third study demonstrates that in mice, at least, cloned embryos contain bona fide "embryonic stem cells," capable of growing into virtually every kind of adult tissue. That suggests people may someday want to clone their cells -- not to make full-grown duplicates of themselves but to create embryos from which precious stem cells could be retrieved. Those stem cells could be grown into replacement tissues for transplantation into the patient, and they would not be rejected because they would match the patient's genes exactly. The three studies, released by scientific journals yesterday, add a sense of urgency to the escalating political and ethical controversy surrounding human cloning and embryonic stem cell research. Congress is poised to consider several anti-cloning bills -- including one introduced yesterday by Sen. Sam Brownback (R-Kan.) and Rep. Dave Weldon (R-Fla.) -- some of which could end up criminalizing not only human cloning, but also cloning of human embryos. A plan by the National Institutes of Health to fund research on human embryo cells has been put on hold pending a Bush administration review of the work's legal and ethical implications. Critics find the work offensive because stem cells are typically retrieved from aborted fetuses or human embryos slated for destruction at fertility clinics. By contrast, Bush and others support work on what are called adult stem cells, which have not shown the same range of potential as embryo and fetal cells. The new report do not suggest cures based on cloning or embryo cells are imminent; indeed, human testing may be many years away. But several scientists said yesterday the studies solidify the argument for federal support of human embryo cell research. "You need to do this kind of research to get to the goal of helping people," said Robert Goldstein, chief scientific officer of the Juvenile Diabetes Research Foundation in New York. "These kinds of results have not been achieved with adult stem cells. And we'd really like to see this helping kids." In the most dramatic, but least well documented, of yesterday's reports, Kiminobu Sugaya and his colleagues at the University of Illinois injected "neural stem cells" from aborted human fetuses into 24-month- old rats, which are equivalent in age to people about 80 years old. The cells developed into neurons and other brain cells, the team says in NeuroReport, a little known online journal. When tested for their ability to learn and remember the location of a movable submerged platform in a tub of milky water, the rats scored better than they had before getting the transplants, on average doing as well as young adult rats. Sugaya said he thought the new cells provided added brainpower and also secreted natural chemicals that nurtured older brain cells. Several neuroscientists gave guarded assessments, saying the report, though promising, lacked critical details. "I'd be really shocked because it's asking a lot for this to happen in old brains," said Stanford University's Irving Weissman, co-founder of StemCells Inc. of Palo Alto, Calif., which hopes to commercialize stem cell cures. "But this is a new field and I'm shocked a lot these days, so who knows?" By contrast, many scientists were enthusiastic about the report by NIH scientist Ron McKay in today's issue of Science. McKay's group turned mouse embryo stem cells into complex, many-celled structures that look and act like islets of Langerhans -- the pancreatic structures that detect high blood sugar levels and respond by secreting insulin. The work suggests that similar clusters, grown from human embryo cells, could be transplanted into children with type I diabetes, who lack functioning islet cells. The islets worked properly when transplanted into diabetic mice, albeit at a level too low to normalize the animals' blood sugar. McKay and others said they think the cells will work better when allowed to mature. "This work is about the most exciting in the diabetes field in the last decade," said Doug Melton, Harvard's chairman of molecular and cell biology. "You don't have to be a rocket scientist to say, 'Let's try this with human ES cells and see what happens.' " In the third study, Teruhiko Wakayama and colleagues showed that when mice are cloned, the resulting embryos contain true stem cells that can be turned into all the major cell and tissue types. In one effort, the team turned stem cells into dopamine-secreting neurons, the type of brain cells that degenerate in Parkinson's disease. A long-term goal is for Parkinson's patients to grow compatible replacement neurons from their own cloned embryos, said Anthony Perry, a co-author of the report in Science. Perry and Wakayama recently left Rockefeller University for Advanced Cell Technology in Worcester, Mass. © 2001 The Washington Post Company http://www.washingtonpost.com/wp-dyn/articles/A7411-2001Apr26.html ******** ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn