Fig. 7. Relationship of ZnT8A levels to GADA, IA2A, and IAA. Assays with ZnT8 constructs were compared with GADA, IA2A, and IAA on the same new-onset T1D samples. Results of linear regression analyses are shown together with a quadrant showing negative and positive in each assay (left lower quadrant, double negative; upper right quadrant, double positive).

Fig. 8. Relationship of ZnT8A levels to age at diabetes onset. New-onset T1D subjects ranging from <1 yr to 18 yr old were grouped in 2-yr intervals to illustrate the level of Zn C-terminal autoreactivity. Prevalence of antibodies to ZnT C-terminal and N/C constructs in relation to one another and to GADA, IA2A, and IAA is shown for the samples in Fig. 5.

Fig. 9. Levels of ZnT8A in prediabetic subjects. ZnT8 C-terminal autoreactivity is shown for 27 prediabetic subjects followed to T1D onset grouped by age up to 4 yr and a 2-yr countdown to diagnosis ( Dx, Dx-1, and Dx-2).

Fig. 10. Individual progression of autoantibodies in prediabetic subjects. ZnT8 C-terminal levels are shown for 10 individuals who were followed from <1 yr to the onset of diabetes. ZnT8A and IAA are grouped (Upper) as are GADA and IA2A (Lower). Autoreactivity in each is indexed as the log₁₀ SD score The area below 4 SD is shaded to denote the cutoff for statistical significance. For each individual, the relationship to the diabetic first-degree relative, gender, HLA-DR genotype, and age at diabetes onset (Dx) is recorded above each. Individuals from the newborn cohort (NEC) have no family history of T1D and were selected on the basis of HLA-DR genotype alone.