Sunday, July 22, 2001

Schwann Cell (SC) Transplantation Trial in MS

Medical history was made by researchers at Yale University School of Medicine when they transplanted myelin-forming cells into the human central nervous system (CNS) on July 17-18. The subject of the trial was a 53-year-old woman suffering from the progressive form of multiple sclerosis (MS). To date no complications have been reported and the patient is recovering well.

The transplant was a phase-1 study designed to prove the safety of the procedure. The team that performed the operation included, among others, Dr. Timothy Vollmer, the principal investigator; Dr. Jeffery Kocsis, in charge of cell preparation; and Dr. Dennis Spencer, who performed the surgery.

The two-part procedure involved obtaining Schwann (SC) cells from the patient's sural nerve and then transplanting them stereotaxically into a demyelinated plaque located in the right frontal lobe of her brain.

The reasons for using autologous SC cells were twofold. Since the cells were derived from the patient herself, the risk of their being rejected was small. In addition, SC and the myelin they produce are not a target of the inflammation that characterizes MS. Accordingly, they may be better able to withstand any new MS attacks than other types of glial cells. The next step will be to biopsy the brain tissue at the site of the implant to determine if the new cells have “taken,” i.e., whether they were integrated into the brain tissue. The biopsy, to be conducted in six months, will also enable researchers to detect possible myelin formation. The new myelin, if any, will be subjected to electron microscopy to verify whether it has normal structure. The six-month interval between implant and biopsy was selected to determine if the transplanted cells can survive long term.

The transplantation procedure will be repeated on four additional MS patients over the next twelve to eighteen months. Two additional patients are scheduled to have surgery six months after the first has been operated on -- a time interval considered adequate for a full safety assessment of the initial surgical procedure. The last two patients would be transplanted in approximately one year. Each group of patients will receive a larger dose of SCs than the previous one.

The MS transplantation trial, as well as its preparation, was financed entirely by The Myelin Project (TMP).

The surgical intervention was preceded by intensive preparatory work to confirm the feasibility of transplanting myelin-forming cells in humans and to ensure that an adequate supply of these would be available when needed.

It was also preceded by several meetings in which the Yale Team was able to compare notes with other TMP Work Group members.

Although initiating the transplantation trial at Yale has been challenging, it will lay the foundation for further transplantation work with SCs and, should these prove ineffective, with olfactory ensheathing cells or other cells of the oligodendrocyte lineage.

The trial gives new hope not only to MS patients, whose population is estimated to be over one million world-wide, but also to patients affected by other demyelinating diseases, such as the leukodystrophies, a group of hereditary diseases that strikes children in their early infancy.

For further information, please contact The Myelin Project at 1 800 8MYELIN