Fetal tissue transplantation
Indications and Procedures (Magill’s Medical Guide, Sixth Edition)
Advances in technology sometimes catapult a society into ethical arenas that are not yet circumscribed by laws and clear moral boundaries. Fetal tissue transplantation is one of these advances. It is a technology that carries the hope of curing a diverse array of severe, often tragic, ailments but one that raises many difficult questions. Tissues from aborted fetuses have been shown in experimental trials to be an excellent source of replacement tissue for patients whose diseases have destroyed their own vital tissues. Parkinson’s, Huntington’s, and Alzheimer’s diseases (in which regions of the brain deteriorate) or juvenile-onset diabetes mellitus (in which insulin-secreting cells of the pancreas degenerate) theoretically could be cured with suitable tissue replacement.
The two sources of tissue used in transplantations, donations from adult cadavers and from aborted fetuses, differ significantly in their suitability. Tissues from cadavers have the severe disadvantage of being immunologically rejected when grafted into anyone who is not an identical twin. The body’s surveillance system that protects against infection is designed to attack and destroy any cells that carry molecular markers identifying them as foreign. Patients receiving tissue transplants from other individuals, therefore, will tolerate the tissue graft only if their immune systems are first suppressed with a battery of potent drugs,...
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Uses and Complications (Magill’s Medical Guide, Sixth Edition)
The major focus for fetal tissue transplantation has been the treatment of patients with Parkinson’s disease, and results have been encouraging. The disease is caused by a deterioration of dopamine-producing regions of the midbrain, the substantia nigra, so named because of the presence of pigmented neurons, which secrete dopamine, in the putamen and caudate nucleus of the basal ganglia. There these neurons send their processes (projecting parts). There is an accompanying loss of motor control causing slowness of movement (bradykinesia), tremors, rigidity, and finally paralysis. Death is most typically a result of accompanying illnesses, such as infections, or caused by the loss of balance and falls. The key drug used to treat the disorder, L-dopa, produces side effects that cause unrelenting and uncontrolled movement of the limbs (dyskinesias) and hallucinations, and the drug loses its effectiveness over time. Advanced patients, who are no longer taking the medication, often remain in a “frozen” state.
A number of patients who have received fetal tissue transplants have shown remarkable improvement and diminished requirements for drug treatment. The first case in the United States to be treated was a man with a twenty-year history of parkinsonian symptoms. He had frequent freezing spells, could not walk without a cane, and suffered from chronic constipation. He also was unable to whistle, a beloved hobby of his....
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Perspective and Prospects (Magill’s Medical Guide, Sixth Edition)
Though controversy surrounds the use of fetal tissue for transplantation, such controversy has not included all facets of fetal tissue research. Indeed, fetal cells were used in the 1950’s to develop the Salk polio vaccine and later the vaccine against rubella (German measles). With the scourge of acquired immunodeficiency syndrome (AIDS), in the 1990’s fetal cells were first used to help design treatments against the AIDS virus. Even the early attempts at fetal tissue transplantation occurred quietly. Reports date as far back as 1928, when Italian surgeons attempted unsuccessfully to cure a patient with diabetes using fetal pancreatic tissue, a procedure repeated, again unsuccessfully, in the United States in 1939. In 1959, American physicians tried to cure leukemia with fetal tissue transplants, but again without success.
The first real indicator that such techniques might work came in 1968, when fetal liver cells were used to treat a patient with DiGeorge syndrome. The success of this procedure resulted in its becoming the accepted treatment for this usually fatal genetic disorder, which results from a deletion of a part of chromosome 22. Because many of the DiGeorge patients are athymic (fail to develop a thymus), they lack T cells, making them immunodeficient. Because the fetal liver supports hematopoiesis (the production of blood cells, including immune cells) during development, fetal liver cells have...
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For Further Information: (Magill’s Medical Guide, Sixth Edition)
Beardsley, Tim. “Aborting Research.” Scientific American 267, no. 2 (August, 1992): 17-18. An excellent encapsulation of the debate over fetal tissue transplantation and the instances in which it has been used.
Beauchamp, Tom, and James F. Childress. Principles of Biomedical Ethics. 6th ed. New York: Oxford University Press, 2009. A classic text that introduces the field of ethics, its theories, and their application to biomedical issues and presents ten cases covering a wide range of issues in biomedical ethics, some of which have led to landmark decisions.
Begley, Sharon. “From Human Embryos, Hope for ’Spare Parts.’” Newsweek, November 16, 1998, 73. Researchers have teased out clumps of cells from human embryos and induced them to burst into a veritable cellular symphony, forming most of the 210 kinds of cells that constitute the human body. These colonies could revolutionize transplantation medicine.
Brundin, Patrik, and C. Warren Olanow, eds. Restorative Therapies in Parkinson’s Disease. New York: Springer, 2006. Covers in depth the ethical, clinical, and scientific issues surrounding neural grafting in Parkinson’s disease and prospects for the future use of stem cell-derived grafts. The book is appropriate for clinicians, scientists, and anyone interested in restorative therapies for the brain.
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