The etiology and pathogenesis of Type 1 Diabetes (T1D) remains largely unknown. In humans insulitis is discrete, affects few islets and is present only in about one third of subjects with recent onset T1D. Also, during the last few years several large phase II-III studies targeting T cell autoimmunity in recent onset subjects with T1D failed to reach the primary endpoint.
Thus, in humans there is limited support for T1D being primarily an autoimmune disease, instead available findings support the view that T1D can be regarded as an innate inflammatory disease affecting the entire pancreas, but with its main clinical manifestations emanating from the loss of the insulin-producing cells.