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> -- > 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