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The following is a paper on the fetal transplant program at the Hospital of the Good Samaritan at Los Angeles. ----------------------------- Begin ----------------------------------------- Two-year Experience of Fetal Mesencephalic Tissue Transplants Deane B Jacques, M.D. Oleg V. Kopyov, M.D., Ph.d., The Good Samaritan Hospital The data accumulated during the last decade from both animal and preliminary human clinical transplantation of ventral mesencephalic fetal tissue offers the promise of ameliorating the kinetic symptomatology of Parkinson's Disease (PD), especially among patients who are refractory to pharmacological treatment of the disease. A large number of PD patients who have been on levodopa therapy for extended periods of time eventually show reduced responsiveness to the drug and eventually develop severe disabling symptoms. PD has received a majority of the attention in neurotransplantation programs because of the strong relationship of this disease to the single neurotransmitter, dopamine (DA). Early histologic studies were able to demonstrate a loss of DA-producing cells in the substantia nigra among PD patients. This, combined with substantial evidence that pharmacological replacement of DA results in reduced somatic anomalies, suggests that intracerebral replacement of DA-secreting cells has the potential to benefit these patients. One of the major goals of the neurotransplantation program at the Hospital of the Good Samaritan was to develop a new technique for treating PD by implantation of fetal ventral mesencephalon (FMV) into the human striatum. In our study we have tried to show that refined surgical technique, optimized handling and processing of fetal tissue, and careful patient selection are the key elements of successful neurotransplantation. Eight men and three women with idiopathic PD (Hoehn and Yahr stage 3-5) underwent fetal brain tissue transplantation using MRI-guided stereotaxis. Clinical evaluations were performed by Professor of Neurology Charles M. Markham (UCLA, Los Angeles) every three to four months several times pre-operatively and at the same intervals post-operatively, consisting of neurological and brief general physical exams, UCLA Parkinson's Disability Scale, Hoehn and Yahr rating, and Unified Parkinson's Disease Rating Scale, all in both "on" and "off" states. Timed tests of walking, hand and foot dexterity and video recordings were made, and self-ratings of symptoms and dyskinesia were completed for seven consecutive days prior to each visit. Fluorodopa PET scans were performed by Barry Snow, M.D. and F. Vinghoets (University of British Columbia) on six patients pre-operatively five to six months and 13 to 15 months post-operatively. A novel hydraulic system was employed to implant solid pieces of fetal ventral mesencephalon of about 0.5-1.0 cubic mm into three needle tracks in the putamen and one needle track in the caudate. Eight patients were operated on unilaterally and three, bilaterally. Each patient received 8-21 pieces of brain tissue (total volume of the implanted tissue is approximately 4-12mm) from one to two human fetuses of seven to nine week's gestation and was given immunosuppressants for 18 months post-operatively. Levodopa was decreased post-operatively to avoid possible injury to fetal tissue and was later gradually increased to optimal level. Four men and two women are distinctly improved at two years post-operatively. Their mean age at transplantation was 49 years; mean disease duration was 13.6 years. Two of these patients received bilateral implants. One of these two patients discontinued antiparkinsonian medication. One woman and three men have not improved. Two of these patients are currently on 60% to 70% of their preoperative medication. All patients of the unimproved group showed no progress of their PD during two to two and one-half years post-operatively. Mean age of the unimproved patients at transplantation was 58.4 years; mean duration of disease was 11.8 years. Our bilaterally-operated patients experienced pronounced inactivity in the immediate postoperative period. Recently, we operated on six patients bilaterally, employing somewhat different surgical and post-operative tactics: 1) All needle, tracks (3-4) were placed in the posterior putamen only; 2) after surgery the pro-operative level of medication was maintained, and only 7-10 days later, we began decreasing levodopa medication; 3) total volume of the implanted tissue was raised up to 25 cubic mm. No one of these patients experienced the above-mentioned post-operative immobility. All of them showed different signs of improvement on the third or fourth day post-operatively. Our results show that age at operation may be a determinant of outcome. Stereotactical targets and amount of the implanted tissue also noticeably affect post-operative regression of Parkinson's Disease. ----------------------------------- End -------------------------------------- Greg Johnson ([log in to unmask])