CHGA and type 1 diabetes mellitus: RegII and specifically its N-terminal fragment (NtfrRII) presented in the context of the NOD MHC allele I-Ag7, as well as the self-antigen chromogranin A (ChgA) recognized by the I-Ag7-restricted BDC2.5 TCR of an islet-reactive T-cell clone [14]; [15] acted as model autoantigens to investigate whether the principle of anti-idiotypic vaccination could be applied to type 1 diabetes and whether vaccines could be generated based on the considerations outlined.