The transplant procedure is no walk in the park -- especially for people who are very ill. It requires that patients first receive treatment with a moderate dose of a powerful immune-suppressing drug to put their disease into temporary remission. Patients then get a treatment that makes their bone marrow produce stem cells, and these cells must be collected in a process that takes three or four days. When these naïve cells have been stored safely in a freezer, the patients then get three days of high-dose chemotherapy to clear the way for the stem cell transplant. They also get a horse serum that kills off all of their T cells.
Finally, the stored stem cells are thawed, heated to body temperature, and transfused back to the patient.
Conn questions whether stem cell transplants really offer a long-term solution. "You're giving the patient's own cells back, so it is hard to see why this would work in the long term," he says. "You would think that it is possible that the same agents that caused [lupus] would cause it again. He also notes the dangerous drugs that suppress the immune system also carry huge risks to the patient.
Because of the promising results in treating severe lupus, Traynor and colleagues already are planning a larger study. Such a trial will require patients to be less severely ill.
The Northwestern University group asks lupus patients not to try to contact them unless they have severe kidney, brain, heart, or lung disease that has already been treated with chemotherapy. "I think for the time being we would encourage only those patients to contact us who have an indication for chemotherapy," Traynor says.
As-yet-unpublished results from another trial of the treatment with multiple sclerosis patients suggest that stem cell transplant halts multiple sclerosis progression but does not reverse the disease.
Early results in patients with rheumatoid arthritis are more disappointing -- only half of patients responded -- but Traynor says work is under way to better adapt the technique to this disease.
Traynor notes that her team intends to expand their research to multiple sclerosis patients, as the procedure appears to be far less traumatic for them than it is for those with lupus. Because they have seen no disease reversal in multiple sclerosis patients even three years after transplant, they intend to begin treating patients at earlier stages of the disease.