Study Using Human Fetal Tissue Transplants Suggests Potential For Spinal Cord Repair

The clinical study was based on a long history of laboratory research showing that transplants of embryonic nerve tissue in laboratory animals could achieve partial anatomical and functional repair following spinal cord injury (SCI). To determine whether this strategy could be successfully translated to humans, a pilot safety and feasibility study was initiated in 1997 in a group of eight patients with progressive posttraumatic syringomyelia.

The study was conducted by a team of neuroscientists and clinical investigators from the University of Florida's College of Medicine, College of Health Professionals, and Evelyn F. & William L. McKnight Brain Institute, and the Malcom Randall Veterans Administration Medical Center, all in Gainesville. One of the team members, Dr. Richard G. Fessler, moved to Rush-Presbyterian-St. Luke's Medical Center in Chicago in July 2000, and is professor of neurological surgery. He is also director of the Institute for Spine Care at the Chicago Institute of Neurosurgery and Neuroresearch (CINN). Another author, Dr. Edward D. Wirth, III, will join the faculty at Rush as assistant professor, neurological surgery, this month.

Syringomyelia, a painful and troublesome complication of SCI characterized by the formation of long cysts in the spinal cord, leads to further tissue damage and neurological problems. The reports present findings for the first two patients in the study, men aged 44 and 51. For 18 months following transplantation surgery, both patients were stable neurologically, and magnetic resonance imaging showed evidence suggesting solid tissue at the graft sites without indications of donor tissue overgrowth.

The study's primary goal is to evaluate the safety of the transplantation procedure with respect to possible early complications and long-term consequences. Although data from the study authored by Wirth and others suggest that transplantation of fetal spinal cord tissue into syringomyelia cavities is logistically feasible and procedurally safe, the long-term consequences of graft survival are still uncertain, say the authors. A secondary goal, addressed in the paper by Thompson and others, is to establish a more comprehensive diagnostic protocol, ranging from neurophysiological tests that monitor subclinical function to standardized questionnaires that measure patients' quality of life.

"We didn't set out to find a cure," said Dr. Douglas K. Anderson, a co-author of the paper. "We wanted to prove that fetal spinal cord transplantation was feasible and procedurally safe, and I think we've done that. We have also provided a template for future studies, which is extremely important. We now have a better idea of how to put these studies together, how to evaluate these patients, and what kinds of outcome measurements to include."

"Before this, there wasn't a lot going on translationally in spinal cord injury," said Dr. Wirth. "Sometimes it takes a study like this to break the ice. We're hoping it will show that with the proper preliminary data these kinds of studies are possible."

"Studies such as these are also important because they take us from the lab bench to the bedside and put us on an important learning curve about human spinal cord injury," added co-author Paul J. Reier, PhD. "They help us identify practical issues in the development of new and safe treatments. In that sense, this experience is already helping us design future laboratory studies that are more in line with real clinical conditions."

"Spinal cord injuries have been documented over the last 5,000 years, yet over that period of time, very little progress has been made in treating them. Transplantation offers us hope for the treatment of spinal cord injury that we had never had before," Dr. Fessler