Upon stratification of the diabetics into new-onset (<12 months) and long-standing (≥12 months—57 months) groups, we found that new-onset diabetics possessed significant expansions of MAIT cells among CD8 T cells, T cells, and total leukocytes, yet long-standing diabetics showed no evidence of increasing proportion of MAIT cells with age among any cellular compartment. Here, CD8A is linked to diabetes mellitus.