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Stem cell advance lauded But harvesting of amniotic fluid has limits, experts say New discovery doesn't deter DeGette By Jim Erickson, Rocky Mountain News January 9, 2007 Stem cells harvested from amniotic fluid may hold great promise for treating disease, but they are not a replacement for embryonic stem cells, Denver-area researchers said Monday. Wake Forest University and Harvard scientists announced Sunday that they have found stem cells in human amniotic fluid that appear to have many of the key benefits of embryonic stem cells while avoiding thorny ethical issues. The stem cells, collected from fluid left over from amniocentesis tests on pregnant women, were able to transform into new bone, heart, muscle, blood vessel, fat, nerve and liver tissues, they reported. "It's a very exciting development that opens up a lot of possibilities," said Brian Freed, director of the University of Colorado Cord Blood Bank in Aurora. Blood from umbilical cords is rich in stem cells that churn out vital blood components: white blood cells, which fight infection; platelets, which promote clotting; and red cells, which carry oxygen. The CU bank contains about 6,000 cord-blood samples. They are used in place of bone marrow to revive leukemia victims and other severely ill patients whose immune systems have been decimated by high-dose chemotherapy. If amniotic fluid stem cells live up to their early promise, parents someday may bank samples that could later be used to treat diseases their children develop, Freed said. "You'd freeze them away, and it could potentially be used 20 or 30 years later to repair something," he said. "To me, that's the exciting potential here." Dr. Carlin Long, chief of cardiology at Denver Health Medical Center, said that amniotic fluid stem cells may allow researchers to "skirt the ethical dilemmas of embryonic stem cell work." Embryonic stem cells are uncommitted "master cells" that can form any type of body tissue. Often, the cells are obtained from leftover embryos at in-vitro fertilization clinics. Progress in the field has been hindered by moral objections to the destruction of embryos. Last year, President Bush vetoed a bill that would have allowed federal funding of research on stem cells from embryos discarded by fertility clinics. Amniotic fluid stem cells "give us another potential source for the future, without the murky ethical waters" surrounding embryonic stem cells, Long said. But he cautioned that "there's a tremendous amount of research effort that's going to have to take place between now and the end point of using these stem cells as therapies." Dr. Curt Freed, head of the clinical pharmacology division at the CU School of Medicine, called the amniotic fluid cells "an exciting addition to the tools available" - but no substitute for embryonic stem cells. Curt Freed and his colleagues have used human embryonic stem cells to treat rats that have a neurological disease similar to Parkinson's disease. "I think they'd be called politically correct stem cells by the Bush administration," Curt Freed said of amniotic fluid stem cells. They should be added to a research arsenal that includes embryonic stem cells and adult stem cells, which normally generate only the types of tissues they are derived from - skin cells or blood cells, for example. "All these stem cell types are on the table," Curt Freed said. "But embryonic stem cells are the only cells that have as their natural fate all the tissues in the body," he said. "And 400,000 frozen embryos are being discarded around the country, so there's no shortage of embryos that are otherwise being destroyed." ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn