By Elizabeth Lopatto - May 9, 2012 12:00 PM MT
An experimental therapy that reprograms the immune system then spurs the growth of healthy insulin-producing cells reversed late-stage diabetes in mice and may lead to a cure for people, researchers said.
Mice with Type 1 diabetes, a form of the disease in which the body’s immune system destroys cells that secrete insulin, were free of illness after scientists shut down the immune attack, reprogrammed the errant cells and coaxed the growth of healthy, new insulin-producers. The study was published today in the journal Science Translational Medicine.
About 3 million Americans have Type 1 diabetes, which is usually diagnosed in children, according to the Juvenile Diabetes Research Foundation. The only treatment is insulin injected to replace the body’s naturally-occurring version of the hormone, which is needed to convert blood sugar into energy. The experimental immune system approach appears promising because it’s the first time diabetes has been cured in mice with advanced disease, said Anita Chong, a medical researcher at the University of Chicago.
“Conceptually, each component isn’t novel, people have thought about them, but put it together and show it can work?” said Chong, who wrote an accompanying editorial to the study. “That’s very exciting.”
There are many more steps before the treatment will be tested in humans, starting with non-human primate models, she said in a telephone interview.
Forms of Diabetes
Type 1 diabetes differs from the more common Type 2 form in that it is an autoimmune disease, in which the immune system kills the cells needed to produce insulin. In Type 2 diabetes, the body produces insulin but cells no longer respond to it.
Diabetics must test their blood sugar several times a day, and sometimes experience hypoglycemia, or dangerously low blood sugar, while they sleep at night.
In the study, the mice were given antibodies to attack two kinds of immune cells that kill the pancreas insulin-producing beta cells. Then the mice had a bone marrow transplant to replenish the vanquished cells. Bone marrow is where blood cells are made, and the transplant let the mice make immune cells that wouldn’t attack the beta cells. A treatment with pancreas growth factor spurred creation of new beta cells.
The study was led by Defu Zeng, an endocrinologist at City of Hope medical center in Duarte, California, and funded by the Iacocca Family Foundation, and private donations from Todd and Karen Wanek and the Davis family.