What are autoantibodies, and how are they related to diabetes?
Henry Rodriguez, MD, responds
Type 1 diabetes is an autoimmune disease. Autoantibodies are formed as part of the process leading to the disease. These can be detected in the blood years before type 1 is diagnosed.
What to Know
The body’s immune system typically defends against harmful invaders, such as infections and cancer. In the process, it produces antibodies, which identify the target to be destroyed. But sometimes the immune system mistakenly attacks the body’s tissues, creating “autoimmune antibodies,” or autoantibodies, to do so. This is the basis for autoimmune diseases.
In type 1 diabetes, the immune system targets the insulin-producing beta cells in the pancreas. During the attack, which can last for years, various autoantibodies may be produced. When most of the beta cells have been damaged or destroyed, the body can’t make enough insulin, and type 1 diabetes develops.
Find Out More
Currently, researchers can identify five autoantibodies linked to type 1 diabetes. Only 2 to 3 percent of the general population has one or more of these autoantibodies, compared with 4 to 5 percent of people who have a mother, father, or sibling with type 1 diabetes. People who have two or more of these autoantibodies have a greater than 90 percent chance of developing type 1 diabetes in their lifetimes.
Research groups such as Type 1 Diabetes TrialNet test people with a family history of type 1 for autoantibodies. Those who test positive may be asked to join a clinical trial so researchers can investigate therapies and learn more about preventing or delaying the disease.
Type 2 diabetes, meanwhile, is not an autoimmune disease, and people with type 2 don’t typically have diabetes-specific autoantibodies. However, some adults develop a type of autoimmune diabetes that progresses slowly, known as latent autoimmune diabetes in adults (LADA). Some people with LADA are misdiagnosed with type 2, based on their age. This can lead to treatment with the non-insulin medications typically used in type 2 diabetes, which are not likely to be effective in LADA.
Researchers use diabetes-specific autoantibodies to predict future risk of developing type 1 diabetes. Doctors may test for autoantibodies to distinguish between type 2 and autoimmune diabetes so that the best treatment can be offered.
Henry Rodriguez, MD, is a professor of pediatrics and the clinical director of the University of South Florida Diabetes and Endocrinology Center in Tampa, and an associate editor of Diabetes Forecast.