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| |  Fetal Pig Cells Transplanted Into Brains Of Parkinson's Patients PHILADELPHIA, PA -- April 16, 1998 -- For the first time in medical history, researchers have transplanted fetal brain cells from pigs into humans to treat a degenerative disease of the brain. Results of this research will be presented at the annual meeting of The American Association of Neurological Surgeons later this month in Philadelphia. This research marks the first time brain cells from an animal have been transplanted into a human. Investigators will present the one year follow-up data on 12 patients who have had moderate to severe Parkinson's Disease for an average of 13.9 years and received the treatment. "We are very excited about this research because our results have been positive and this method of treatment has the potential to help not only Parkinson's patients, but also patients with other degenerative brain diseases like Alzheimer's, Huntington's and Lou Gehrig's Diseases," said neurosurgeon James Schumacher, MD, who is the primary author of the paper. Parkinson's Disease affects over one million people in the United States and is characterized by tremor, slowness in movement, difficulty walking, balance problems, difficulty writing and holding objects. Parkinson's Disease is caused by a chemical imbalance in the brain. Normally, the substantia nigra part of the brain produces two chemicals, dopamine and acetylcholine, in equal amounts. These chemicals are called neurotransmitters and are sent to the striatum, another part of the brain, that controls movement and balance. When the body wants to make a movement, anything from walking to picking up a cup of coffee, the striatum releases these neurotransmitters through the nervous system to the appropriate muscles, producing smooth, coordinated movement within a fraction of a second. In Parkinson's Disease, the cells in the brain that produce dopamine begin to die, leading to an imbalance between the two neurotransmitters. This imbalance causes the shaking, hesitant movements that characterize Parkinsonian patients. Researchers do not know the cause of Parkinson's Disease. "Parkinson's Disease comes on slowly and at first may be as simple as an annoying shaking in the hands," said Douglas Kondziolka, MD, professor of neurosurgery at the University of Pittsburgh and a leading expert in Parkinson's Disease treatment. "But as time goes on, patients cannot write, cannot drink from a glass and have great difficulty in producing the muscle movements needed to walk." Treatment for Parkinson's Disease traditionally has included medications to reduce the amount of acetylcholine in the brain or to force the remaining cells to produce more dopamine than normal to restore the balance. In recent years, surgical techniques such as pallidotomy, thalamotomy and deep brain stimulation, have significantly reduced the symptoms of Parkinson's in patients who did not respond to drug therapy or who have become resistant to the medications. These surgical procedures involve making lesions, or cuts, in specific parts of the brain in order to prevent the symptoms of Parkinson's Disease, such as tremor. "With cell transplantation, instead of deconstructing, we are reconstructing," Dr. Schumacher said. "The cells we implant are actually producing dopamine and, therefore, are repairing the brain, not just the helping to rebalance neural activity." In cell transplantation, cells are taken from fetal, or unborn, developing, pigs and are transplanted into a human brain. These cells are primitive and are not fully developed. "The timing is extremely important," Dr. Schumacher said. "We need the cells to be primitive so they are not yet developing dopamine, but they have to be just about ready to start. At the point we take the cells, they have not yet been differentiated from human brain cells." Transplanting human fetal cells is also being studied, but the lack of availability of these cells have hampered these efforts. In Dr. Schumacher's research, both fetal pig cells and patients were treated with anti-rejection methods and no overt signs of rejection or untoward events have been seen. Heart valves from pigs have been used for human transplantation in the past with significant success and little rejection problems. "This research is a stepping stone and is something that we will continue to investigate more thoroughly over the next few years," Dr. Schumacher said.
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