Dysrulation of T cell peripheral tolerance in type 1 diabetes.

Type 1 diabetes (T1D) is a T cell-mediated autoimmune disease in which the insulin producing beta cells are destroyed. The breakdown of beta cell-specific self-tolerance by T cells involves a number of dysregulated events intrinsic and extrinsic to T cells. Herein, we review the key mechanisms that drive beta cell autoimmunity, with an emphasis on events that influence the expansion and differentiation of pathogenic T cells in the periphery.