CD8A and type 1 diabetes mellitus: NOD mice spontaneously develop T1DM; however, they do not develop pancreatic islet inflammation if they lack MHC class I molecules to present antigens to CD8+ T cells.72 Additionally, depletion of CD4+ T cells in NOD mice inhibits the development of T1DM.73 Studies have shown that intestinal flora can induce the proliferation of specific types of T cells, thereby influencing the immune response.