Medicine: Help From The Unborn Fetal-cell

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Indeed, surgeons at Shanghai People's Hospital have been treating diabetics with fetal islet cells since 1982. Of 39 patients monitored for more than two years, three no longer need insulin shots and the others have reduced their insulin requirements anywhere from 30% to nearly 100%. In some of these diabetics, the progress of related kidney and eye disease has been either halted or reversed. Results in the U.S. have been less remarkable. Only three of 17 diabetic patients treated so far by Lafferty's colleague Everett Spees, chief of transplant surgery at AMI St. Luke's Hospital in Denver, are any less dependent on insulin, and none of them by more than 30%. "We don't know how long it takes for the fetal tissue to mature," Spees explains, "nor how much of it we need to treat an adult."

Swedish researchers at the Karolinska Institute and the University of Lund hope to transplant fetal brain cells into the brains of patients with Parkinson's disease. Says Dr. Anders Bjorklund: "The cells of an eight-to- twelve-week-old fetus are still developing and can be 'persuaded' to take on particular functions." In this case, the function is producing dopamine, a neurotransmitter that is in short supply in Parkinson's victims. Bjorklund predicts a trial with humans will begin "within a couple of years."

Michael Harrison, a pediatric surgeon at the University of California at San Francisco, believes fetal liver tissue may be the key to curing hereditary blood diseases like thalassemia, in which red blood cells carry defective hemoglobin molecules. Reason: fetal liver tissue contains cells that migrate and become bone marrow, the substance that produces blood cells. Harrison has used this tissue to change the blood type of unborn sheep, and is gearing up for a trial in humans. "We're perfecting our techniques and looking for an appropriate case," he says. "You don't want to cut corners on something like this. We need the right circumstances, both biologically and socially."

Concern about those circumstances extends beyond the medical community. While few object to the use of tissue from fetuses that have aborted spontaneously, the Roman Catholic Church and right-to-life groups draw the line when intentional abortion is involved. But doctors warn that spontaneously aborted fetuses often have genetic defects that make their tissue unacceptable for implantation. As fetal-cell surgery advances, they fear, the need for tissue -- whatever the source -- will grow. Warns Ethicist Arthur Caplan of the Hastings Center in Hastings-on-Hudson, N.Y.: "The use of fetuses as organ and tissue donors is a ticking time bomb of bioethics."