Moreover, Foxp3-deficient scurfy mice on the diabetes-prone NOD background (NOD.Foxp3sf) develop exocrine pancreatitis and peri-insulitis, but do not develop insulitis and overt diabetes, unless the CD4+ T cell receptor (TCR) repertoire of NOD.Foxp3sf mice is artificially restricted to a single highly diabetogenic specificity by transgenic expression of the BDC2.5 TCR (11). This evidence concerns the gene CD4 and diabetes mellitus.