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Pig cell transplants show early promise for Parkinson's treatment Copyright © 1998 Nando.net Copyright © 1998 The Associated Press NEW YORK (April 13, 1998 http://www.nando.net) -- Researchers are finding encouraging early results for treating Parkinson's disease by transplanting fetal pig cells into patients' brains. In one case, a man who spent most of his time in a wheelchair is "really up and moving ... He can play golf again," said neurosurgeon Dr. James M. Schumacher. Another patient has been able to stop using a cane to walk, said Schumacher, of Neurological Associates in Sarasota, Fla. Schumacher will report on a study of pig cell transplants later this month at the annual meeting of the American Association of Neurological Surgeons. The study was designed to look at the procedure's safety rather than effectiveness, and Schumacher said no major side effects appeared. Most of the recipients improved to some degree, he said. As a group, the 11 patients improved about 14 percent on standard rating scales by six months after surgery and about 20 percent by a year afterward, Schumacher said. One other patient died from a cause unrelated to the treatment. "The patients continually improve," he said. "They're not made immediately better, but they improve over time as the graft matures." Schumacher stressed that the transplant results are only preliminary. "It's very early. It's like the little Wright brothers' plane has gotten off the ground. Don't buy any tickets to Tokyo yet," he said in a elephone interview. More than a half-million Americans have Parkinson's, which produces such symptoms as tremors, rigidity and slowing of movement. Medicines can help, but often lose effectiveness over time. So scientists have een looking at ways to fix the basic problem, which is a deficit of a chemical messenger called dopamine in a particular part of the brain. For a decade, scientists have been studying transplants of human fetal brain cells into patients' brains. The cells pump out dopamine. But using human fetal tissue is controversial, and Schumacher said it's also logistically hard to round up enough fetal brain cells of just the right age to work. So he and colleagues have turned to pig cells, doing the first transplant three years ago. But using pig cells raises another concern that has shadowed the prospects of using animal organs for transplants into people: will animal germs get a free ride into the human population, creating deadly new human diseases? "As of now we have found no evidence that any viruses have been transferred," Schumacher said, "but further studies remain to be done. There's a lot to learn." To do the transplant, a surgeon drills a hole about the size of a pencil eraser in the top of a patient's skull. The pig cells are suspended in a liquid that slowly seeps into the brain through a tube. The operation, done under local anesthesia, takes about three hours. Schumacher said researchers are planning another study, with bigger doses of pig cells, for better assessment of how effective the transplants can be. Dr. Curt Freed of the University of Colorado, who is studying transplants of human fetal tissue for Parkinson's, said Schumacher's preliminary results look promising. If scientists can keep the human brain from rejecting the pig cells, "this could become an important transplant therapy," he said. By MALCOLM RITTER, AP Science Writer