Researchers have demonstrated for the first time that the progression of Type 1 diabetes can be halted -- and possibly reversed -- by a stem-cell transplant that preserves the body's diminishing ability to make insulin, according to a study published today.
The experimental therapy eliminated the need for insulin injections for months or even years in 14 of 15 patients recently diagnosed with the disease. One subject, a 30-year-old male, hasn't taken insulin since his stem-cell transplant more than three years ago, according to the study in the Journal of the American Medical Assn.
The study suggests a new avenue for treating the intractable disease, in which the immune system destroys insulin-producing beta cells in the pancreas. Without insulin, patients can't metabolize sugar and run the risk of developing nerve damage, cardiovascular disease, kidney failure and blindness.
Patients with Type 1 diabetes typically compensate by monitoring their blood-sugar levels every few hours and injecting themselves with insulin as many as five times a day.
After the stem-cell treatment, "patients are absolutely medication-free -- they're off insulin," said Dr. Richard Burt, chief of the Division of Immunotherapy for Autoimmune Diseases at Northwestern University's Feinberg School of Medicine in Chicago and senior author of the study.
The strategy is similar to an approach that has shown some success in treating other immune system disorders, such as rheumatoid arthritis, lupus and multiple sclerosis.
"We all realize that without addressing the problem at the level of the immune system, we'll never really beat Type 1 diabetes," said Dr. Francisco Prieto, who treats diabetics in his Elk Grove, Calif., practice and wasn't involved in the study. "This is very encouraging work."
Burt and his colleagues cautioned that they didn't know whether the fix was permanent and, if it was not, how long it would last. One of the subjects was insulin-free for one year but relapsed after a respiratory viral infection, said lead author Dr. Julio Voltarelli, associate professor of medicine at Ribeirao Preto medical school at the University of Sao Paulo in Brazil.
The researchers also cautioned that the process was not without risk, because patients are vulnerable to infection during part of the therapy. Burt's research group at Northwestern has performed 170 stem-cell transplants to treat a variety of immune system disorders, and two patients have died from the treatment.
