Since the late 1990s, adult stem cell therapy has been used experimentally to treat multiple sclerosis (MS), type 1 diabetes, rheumatoid arthritis, and several other diseases of the immune system, as well as heart disease.
Northwestern University researcher Richard Burt, MD, and colleagues summarize results from roughly 60 of these studies involving about 2,400 patients in a review published in tomorrow's edition of The Journal of the American Medical Association.
Burt pioneered the research on adult stem cells for the treatment of autoimmune disease. He tells WebMD that the potential uses for stem cell therapy are only now beginning to be understood.
"Traditional medicine is about three approaches -- drugs, surgery, and radiotherapy," he says. "Stem cell therapy represents a fourth arm of treatment that in some cases will be combined with other treatments and in other cases will stand alone. We are seeing the tip of the iceberg right now."
Stem Cell Patients Tell Their Stories
Barry Goudy, 48, and Tom Van Lieshout, 76, are both believers. Both are Burt's patients.
"I played hockey and racquetball and had always been very athletic, but I just couldn't do it anymore," he says. "I got to the point where I couldn't walk up the stairs without dragging my leg."
Goudy spent a month in the hospital, including five days of chemotherapy to knock out his immune system. But he tells WebMD he has been free of MS symptoms ever since.
He says he's now playing hockey and racquetball again, and is "living my life."
"I've had five good years that I wouldn't have had," the Detroit automobile sales representative says.
He says he was in such excruciating pain before having the treatment that he could only walk 50 to 100 yards at a time.
"When I went into the hospital I walked from the parking ramp to the entrance, which was a couple hundred yards, and I had to stop three times," he tells WebMD. "Just a few days after [the transplant] I was able to walk three blocks to the drugstore and back."
Stem Cell Therapy
Much of the attention and all of the controversy surrounding stem cell therapy has focused on embryonic stem cells -- cells harvested four to five days after an embryo is fertilized.
Adult stem cells exist to replace damaged or aging cells, and they are found in tissue throughout the body of adults and in the blood and bone marrow, where cells are much easier to harvest.
Stem cell therapy has been used for many decades to treat leukemia and other cancers, but the treatment-related death rate is high due to the aggressive chemotherapy and/or radiation used to dramatically suppress the immune system and kill cancer cells.
This type of treatment has generally been considered too dangerous for less life-threatening diseases, and in the review by Burt and colleagues the treatment-related death rate was 13% among patients with autoimmune diseases who had the most aggressive, bone-marrow suppressing treatments.
In contrast, the death rate among patients who had a less aggressive treatment known as a non-myeloablative transplant -- or "transplant light" -- was less than 1%.
Twenty-six studies involving 854 patients with various autoimmune diseases were included in the review.
Most of the studies involved patients with MS, who fared best when they were treated with non-myeloablative regimens.
The same thing appears to be true for patients with type 1 diabetes. The less aggressive and dangerous treatment also shows promise for the treatment of rheumatoid arthritis, Crohn's disease, lupus, and other autoimmune diseases.
Seventeen studies involving just over 1,000 heart attack patients and 16 studies involving just under 500 patients with coronary artery disease suggested a "modest benefit" for the treatment in cardiovascular disease, the researchers conclude.
Many important questions remain about the use of stem cell therapy in non-malignant disease. And only time will tell if patients like Goudy and Lieshout are cured of their diseases.
"We don't yet know what role this therapy will play in the treatment of MS," National MS Society Vice President for Biomedical Research Patricia O'Looney, PhD, tells WebMD. "We just don't have enough data."
Stem cell researcher Stanton L. Gerson, MD, of Case Medical Center's Ireland Cancer Center, says the therapy may hold the key to better treatments or even cures for a wide range of diseases.
"My sense is that this treatment will soon become mainstream for a least some of these diseases," he tells WebMD.