Multiple β cell autoantigens are recognized by human CD4+ and CD8+ T cells found in peripheral blood, as well as the islets of T1D subjects; many of which are also targeted in the NOD mouse diabetogenic response (e.g., insulin, GAD65, IGRP, and ZnT8) (4, 25, 28, 57). This evidence concerns the gene GAD2 and type 1 diabetes mellitus.