In a mouse model of diabetes, depleting CD8+ T cells temporarily cured the disease, while depleting CD4+ T cells failed to halt its progression.[34] This suggests that activated autoimmune T cells are predominantly CD8+ T cells, consistent with the observation of specific IFN-γ CD8+ T cells infiltrating the islets and almost completely destroying islet β cells in hyperglycemic mice treated with PD-L1 antibodies. This evidence concerns the gene IFNG and diabetes mellitus.