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THE BOSTON GLOBE APRIL 20, 1995 MAN RECEIVES PIG BRAIN CELL IMPLANT By Richard Saltus (Globe Staff) The first animal-to-human transplant of brain cells has been carried out at Lahey Hitchcock Clinic in Burlington, by researchers who placed five clumps of tissue from fetal pig brains into the brain of a 59 year-old man with severe Parkinson's disease. If successful, the cross-species transplant could eliminate the need for tissue from aborted fetuses, which is now used in brain grafts. Results won't be known for several months, the scientists said yesterday. The clinic announced the operation yesterday, the day after it was carried out, and said the patient was recovering normally. The unidentified man is the first of six patients scheduled to receive the implants in one side of the brain, leaving the other side intact, in a test of the procedure's safety. The trial is being carried out in cooperation with the Food and Drug Administration, said Schumacher. "As in trials with human tissue, we expect to see a reversal of many of the signs and symptoms of Parkinson's," said Dr. James M. Schumacher, a Lahey Hitchcock neurosurgeon who is heading the experiment. Parkinson's, an incurable degenerative brain disease, affects some 1.5 million older Americans, who progressively develop stiff, jerky movements and tremors and may become virtually "frozen" for periods of time. The death of nerves in certain brain centers causes a deficiency of dopamine, a chemical messenger that is crucial for smooth control of walking and other movements. Drugs that supply dopamine can help, but over time they lose their effect. On the premise that transplanting healthy dopamine-containing nerves will provide a more natural and long-lasting supply of the chemical, surgeons in the United States and abroad have performed brain grafts in a number of patients - with varying results. Recent reports are more encouraging, with Swedish scientists demonstrating that about 10 percent of implanted tissue survives and grows permanently into the patient's brain wiring, and improves symptoms. In one or two cases, the patients have improved to a point of not needing drug treatment, said Dr. Ole Isacson, a researcher at Harvard University and McLean Hospital who is involved in the trial. But research has been held back, particularly in the United States, by moral and legal opposition to using aborted fetuses as a source of tissue for implants. In experimental implants into rodents and non human primates, tissue from animals "has given us similar results" to those yielded by human grafts, said Isacson, head of the Neuroregeneration Laboratory at McLean. "The human brain is organized differently and is different in size from that of animals, but is similar on the cellular level." Cells transplanted into the brain are less likely to be rejected by the immune system than transplants of other organs, but some rejection can occur. Patients in the Lahey Hitchcock trial are receiving the immunosuppressive drug cyclosporin and probably will need it for life. The patient who received the implant Tuesday was awake and under local anesthetic during the four-hour operation, which involved the use of sophisticated imaging machines to guide surgeons to the correct locations in the brain. A Lahey spokeswoman said the hospital costs of the trial are being borne by an unidentified private source. The fetal pig cells, obtained from 25-week-old embryos from pigs grown and carefully screened for infectious agents, are supplied by Diacrin Inc. of Cambridge. Chief executive officer Thomas Fraser said the company is working on techniques to "mask" cells from animals so that the recipient's immune system doesn't recognize them as foreign and reject them. A veteran Parkinson's researcher, Dr. William Langston of the California Parkinson's Foundation, said the work is "potentially very important" because it could provide a solution to the problem of supplying tissues for implants. However, he said, "I am shocked that they announced this" infant operation "because that's not the way you're supposed to do science." Usually, the experiment would be reported in scientific journals after several patients had been treated and results had been evaluated by other scientists, said Langston.