At 16 weeks of age, total IgG1, IgG3, and IgA did not differ across treatment groups (Fig. S5E–G) or between progressors and non-progressors to T1D (Fig. S5H–J), but total serum IgM was elevated in the 250 μg CTB-hpINS-treated animals (Fig. 6A) that progressed to diabetes (Fig. 6B). Here, IGHG3 is linked to type 1 diabetes mellitus.