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Hi all -- The following excerpts from an article from the July 16th Chicago Tribune examines the differences between adult stem cells and embryonic stem cells. Are they really equal options for research? Full Article at: http://www.chicagotribune.com/news/nationworld/article/0,2669,1-010716022 8,FF.html Science explores stem cell options By Jeremy Manier and Ronald Kotulak, Tribune staff reporters. Tribune staff reporter Peter Gorner contributed to... " As the political fortunes of embryonic stem cell research hang in the balance, scientists increasingly are looking for alternatives in case federal funding for work on human embryos falls through. ... Opponents of such research argue that some alternatives are at least as promising as embryonic stem cells, which may be able to regenerate tissue to cure ailments such as diabetes and Parkinson's disease. The desperate search for other research options has led to possible stem cell sources in adult bone marrow, cells made by mimicking the process of cloning and even fat tissue. Yet some of the alternatives, such as fat, almost certainly are dead ends, according to stem cell experts. Adult stem cells from bone marrow show more promise and have reached human trials for some diseases. Even so, experts say, such cells have lacked the power of embryonic stem cells to form virtually any type of tissue. For those reasons even the most prominent adult stem cell researchers say they support federal funding of work on cells from embryos. "The vanguard of the field has really been the embryonic work," said Dr. Ira Black, a neuroscientist from the University of Medicine and Dentistry of New Jersey. Last year, Black presented the first report showing adult stem cells from blood could be transformed into brain cells..." "Using adult stem cells Although adult stem cells can become several different tissue types, there is little hard evidence that they can replicate essential functions, said Dr. Irv Weissman, a Stanford University scientist and pioneer of adult stem cell research. "We have a small number of intriguing experiments in mice where we could show, for example, that a blood-forming stem cell could turn into liver," Weissman said. "But almost all of the other experiments that were done, even with mice, are not rigorous experiments--they're sort of flashes out of the box." Most adult stem cell research has focused on cells from bone marrow. A potential advantage of adult stem cells is that unlike embryonic stem cells, which have never been transplanted into humans, doctors have decades of experience with bone marrow transplants for cancer patients..." Misinterpretations "Some adult stem cell researchers, however, said the implications of their work have been exaggerated. When Dr. Diane Krause of the Yale University School of Medicine published a study in May suggesting bone marrow cells could form liver, lung and skin cells, some opponents of embryonic research claimed the results showed adult stem cells are just as flexible as stem cells from embryos. Yet Krause said her study could not show the cells were functioning in their new roles. "It was based on 10 mice," said Krause, who supports embryonic stem cell research. "I would call that scant evidence. That doesn't mean it's not true. But we have no idea how it happened." Similar misinterpretations sprang from a much-publicized April study in which researchers obtained muscle and bone cells from fat tissue, according to Gearhart of Johns Hopkins. Because the researchers never isolated individual stem cells, they could not know if the new cells came from fat or from blood that circulated through the fat tissue, Gearhart said. Many researchers said the relative strengths of adult and embryonic cells will never be known until they can be tested against each other. And that is almost impossible without federal funding for embryonic cell research, said Dr. Evan Snyder, a stem cell researcher at Harvard University...." ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn