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March 13, 2001 The Week in Science: The Arrow of Progress The arrow of progress does not invariably point forward. A serious disappointment has been inflicted on patients with Parkinson's disease and those who hoped to treat it with injections of brain cells from aborted fetuses. The technique, promising in concept and experiment, seemed ready to be tested by the final arbiter of truth, a double-blinded clinical trial in which neither patients nor doctors would know who had received the real treatment and who a pretend one. But the result, published this week, showed that patients get no benefit on the whole, at least from the treatment in its present form. Parkinson's disease is caused by the unexplained death of cells in a special region of the brain that produce dopamine, a chemical the brain uses in transmitting nerve signals, particularly those that control movement. The idea of the treatment was to take dopamine-producing cells from the same brain region of aborted fetuses and inject them into patient's brains, in the hope that the fetal cells would survive whatever was killing the patient's own cells. On a case by case basis, the treatment seemed to work, but then experimental drugs and treatments often do seem more promising than they really are, because both patients and physicians and so keen for them to work. In the controlled study, the cells didn't seem to do anything much for older patients, but helped some younger patients initially. Unfortunately the fetal cells worked too well. They grew and produced too much dopamine, causing uncontrolled limb movements which were not reversible. The patients in the control group, who had been told they could have the real treatment if it worked, all decided not to. "The operation was a success but the patient died" is a cynical comment on medicine's often partial victories but it seems to apply in this case. The fetal cells do grow and do produce dopamine. The only thing worse than failure would have been success: there are not enough aborted fetuses to treat more than a tiny percentage of Parkinson's patients. The concept of cell therapy seems the right way to go because the drug L-dopa works fine at first but then loses its power. After the work with fetal cells started, human embryonic stem cells have become available. Mouse embryonic stem cells seem to work well in treating mice with a mouse version of Parkinson's. Human embryonic stem cells could probably be engineered in some way so as to make the treatment reversible in the event of side-effects, for example by making them vulnerable to a specific drug. Human embryonic stem cells were first cultured in November 1998 but university researchers dependent on government grants are still waiting to use them because lobbying by foes of abortion has blocked government approval. By NICHOLAS WADE Copyright 2001 The New York Times Company http://www.nytimes.com/2001/03/13/science/13WEEK.html?searchpv=site01&pagewa nted=print janet paterson, an akinetic rigid subtype, albeit perky, parky PD: 54/41/37 CD: 54/44/43 TEL: 613 256 8340 EMAIL: [log in to unmask] "A New Voice" home page: http://www.geocities.com/janet313/ . "New Voice News" latest posts: http://groups.yahoo.com/group/nvnNET/ . ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn