MGH study shows vaccine could permanently reverse type 1 diabetes

Two years after beginning a groundbreaking phase II clinical trial in reversing type 1 diabetes, researchers from Massachusetts General Hospital have discovered that a vaccine could permanently reverse the disease.

The five-year long, mid-stage clinical trial is looking at the bacillus Calmette-Guerin vaccine, an inexpensive and already generic vaccine that is used around the world to prevent tuberculosis.

Dr. Denise Faustman, director of the Massachusetts General Hospital immunobiology laboratory and principal investigator of the trial, said interim results show that unlike other vaccines that irritate white blood cells to prompt an immune response, the BCG vaccine affects white blood cells at the genetic level, regulating which genes are expressed and which are not. The body consequently stops producing the abnormal white blood cells responsible for the autoimmune disease, suggesting that the vaccine could permanently reverse type 1 diabetes.

“The vaccine actually resets your genes to restore normality,” Faustman said in an interview. “What it is showing is it’s not merely the vaccine you’re being given and it causes inflammation or an immune response. It’s actually working at the most basic DNA level to normalize expression of genes related to this abnormal immune response.”

The findings were presented Saturday during the 77th Scientific Sessions of the American Diabetes Association, one of the largest diabetes gatherings in the country.

The findings not only bring a broader understanding to ongoing studies of the vaccine for type 1 diabetes, but also explain why the vaccine is so effective in treating other autoimmune disorders — from multiple sclerosis (studies with the vaccine are ongoing in Italy) to food allergies (studies with the vaccine are ongoing in Australia).

“It’s because the immune system hasn’t bent been reset correctly in childhood,” Faustman said. “There are trials using this vaccine to reverse allergies in Australia. It’s putting the environment back into people.”

Used in China, Africa and South America to vaccinate against TB, the BCG vaccine has been utilized 4 billion times over the last 100 years. Last year alone, 100 million doses of the vaccine were given to newborns. Because TB isn’t common in the U.S., children here do not receive the vaccine.