Fetal cells tried for Huntington's.

The controversy surrounding fetal tissue research has slowed, but not halted, progress in the field. The use of transplanted fetal brain tissue to replace brain cells lost in Parkinson's disease patients has proved promising enough that researchers have begun to test the strategy on people with Huntington's disease, another neurodegenerative disorder. Oleg V. Kopyov of Good Samaritan Hospital in Los Angeles now reports that the first three Huntington's patients receiving a transplant of fetal brain cells have all experienced some improvement in motor and cognitive skills.

The most severely affected patient, who had been wheelchair-bound, briefly regained the ability to walk, though his condition has since deteriorated dramatically, says Kopyov. The mental and motor skills of the two other patients, whose symptoms were much milder, continue to improve 8 to 9 months after surgery, he adds.

It remains unclear whether or how the fetal cells are helping these patients. Experience from work on Parkinson's disease suggested that patients would see no improvement for many months, a period during which fetal cells presumably grow and establish connections within the brain. Yet Kopyov's group found that the three Huntington patients began to improve within weeks of the surgery. "I don't understand it," admits Kopyov.

Another research group has also begun treating Huntington's patients with fetal cells, but this team uses porcine tissue. Five Huntington's patients have recently received fetal pig brain cells, and another seven transplants are scheduled, says Jonathan H. Dinsmore, director of cell transplantation at Diacrin, the Charlestown, Mass., biotech firm funding the trial. Dinsmore and his colleagues hope to establish that fetal brain cells from pigs offer a safe substitute in treating Parkinson's and other neurological illnesses (SN: 10/7/95, p. 230), thus avoiding the political controversy of using human fetal cells and the difficulty of obtaining tissue.

Dinsmore cautions that it will take a significant amount of time and testing to determine whether fetal brain cells, human or porcine, help people with Huntington's disease. "You need at least a year's data to know if there's anything more than a placebo effect," he says.