CHGA and type 1 diabetes mellitus: We first sought to use this approach to ascertain the ability of the 4.1-TCR to recognize previously described T1D-relevant autoantigens (19, 20), including pro-insulin (INS), chromogranin A (ChrA), islet amyloid polypeptide (IAPP), islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP), glutamic acid decarboxylase 65 (GAD65), zinc transporter 8 (ZnT8), and islet tyrosine phosphatase 2 (I-A2).