We did observe an increase in the frequency of IL-17+ cells within the subpopulation of CD45RA− CCR6+ T cells in type 1 diabetes patients (geometric mean 4.26% [95% CI 3.25, 5.58]) compared with healthy donors (geometric mean 3.61% [95% CI 2.68, 4.86], p = 0.04; Fig. 1d and Table 3), which was also replicated (p = 0.03; Fig. 1f) in the subset of 38 donors activated using different PBMC stimulation conditions (500 ng/ml ionomycin). Here, IL17A is linked to type 1 diabetes mellitus.