Mast cells produce a large amount of the proinflammatory cytokine interleukin-6 (IL-6), which favors differentiation of IL-17-secreting T-cells rather than the tolerogenic Tregs differentiation, contributing to the damage of insulin-producing β-cells and the progression of T1D [80, 81]. The gene discussed is IL17A; the disease is type 1 diabetes mellitus.