More Understanding Of The Origins Of Type 1 Diabetes?

Working in mice, researchers demonstrated that to enter key areas of the pancreas known as the islets of Langerhans, immune cells known as T cells must recognize a marker on the surface of insulin-producing cells housed there. T cells play a key role in regulating immune response. Once inside the islets, T cells trigger the inflammation that can lead to destruction of the insulin-producing beta cells. The result is type I diabetes.

The report answers a fundamental question about the role of T cell entry and accumulation in the islets in development of type I disease, a disease that affects as many as 3 million Americans. The research appears in the October 16 edition of the journal Immunity. Dario Vignali, Ph.D., is the paper's senior author and vice chair of the St. Jude Immunology department.

The St. Jude results contradict a widely held theory that only a small percentage of T cells that infiltrate the islets were actively involved in causing type I diabetes. The old scenario held that most of the T cells found in the islets were recruited to the site by a small number of specialized T cells. Those recruited or bystander T cells were thought to play no role in causing diabetes.
Furthermore, it was thought that any T cell could gain access to the islets.