A second study of transplanted fetal cells has failed to show a therapeutic benefit in Parkinson's disease patients and produced serious side effects in some patients, the Wall Street Journal reports. The findings are "a blow" to researchers who had thought that transplants of brain tissue from aborted fetuses could stem the effects of the disease.

For the study, which involved 34 participants, Mount Sinai School of Medicine and University of South Florida researchers infused brain tissue from up to eight aborted fetuses, ranging from six to nine weeks old, into 23 patients with Parkinson's disease. Brain scans of the participants indicated that the transplanted cells functioned "normally," but researchers were unable to "find any measurable improvement on tests of motor and other skills," according to the Journal.

In addition, the "most severe setback" was side effects that included uncontrolled limb movement in 13 patients. Three patients experienced such severe side effects that they required additional surgeries to control them. The study -- the second of two federally funded studies to examine if fetal cells can repair brain tissue in Parkinson's patients -- could lead to a "winding down" for future fetal-cell transplants, the Journal reports.

Anthony Lang, a Parkinson's expert at Toronto Western Hospital in Canada, said, "This is a surprising result that forces reconsideration of transplantation without a great deal more research." The study could also have implications for embryonic stem cell research, which has recently "upstaged both politically and scientifically" research using fetal cells. Some researchers consider stem cells "more versatile" than fetal cells, according to the Journal (Regalado, Wall Street Journal, 12/3).

President Bush in August 2001 established guidelines limiting federal funding for human embryonic stem cell research to 78 stem cell lines that were created prior to his announcement (Kaiser Daily Reproductive Health Report, 11/20). Research using fetal cells, however, is covered by a separate rule established in 1993 under former President Clinton, and Congress passed legislation to ensure that women are not "paid or induced to have abortions to provide tissue" for the research.