Non-cohoused NOD.NOD2−/− mice exhibit reduced T1D incidence and a decrease in CD4+ IFN-γ+/CD8+ IFN-γ+ (Th1/Tc1) and CD4+ IL-17+/CD8+ IL-17+ (Th17/Tc17) T cells in PLNs, indicating that NOD2 activation regulates T1D development by altering the composition of gut microbiota and by modulating the adaptive immune response (86). The gene discussed is IL17A; the disease is type 1 diabetes mellitus.