New research from a University of Colorado Denver study has revealed a new class of antigens that may be involved in the development of type 1 diabetes.
In this type of diabetes, the key question is why the immune system turns against the body's own tissues - in the case of type 1 diabetes, insulin- producing beta cells located in the pancreas are targeted by immune cells, especially T cells. Without insulin, a hormone that maintains blood glucose, the results can be life-threatening, and the new results could help scientists come up with the first-ever cure for this deadly form of diabetes.
"Our lab studies the type of T cell known as a CD4 T cell," Kathryn Haskins, corresponding author of the article, said in a press release. "We have focused on autoreactive CD4 T cells using a mouse model of autoimmune diabetes. We have been especially interested in identifying the antigens that activate these T cells."
Identification of these antigens will allow scientists to detect autoreactive T cells early in the disease and in at-risk individuals, aiding the process of identification and treatment. If they can develop a method of turning off destructive T cells, they may be able to prevent the disease altogether.
The team examined the groups of beta cells that contain antigens for autoreactive CD4 T cells in order to isolate autoantigens from type 1 diabetes and discovered a new class of antigens made up of insulin fragments attached to peptides and other proteins that are also observed in beta cells. This unique fusion stimulates the creation of hybrid insulin peptides that are not present in an individual's genome.
Modified peptides are tagged as "foreign" to the immune system, and this finding could explain why some become targets for autoreactive T cells. Furthermore, it could help in the understanding of other autoimmune diseases.
The findings were published in the Feb. 12 issue of Science.
