The BDC-2.5 clone was identified among a panel of islet-specific CD4+ T cell clones expanded from the pancreas of a diabetic NOD mouse and was capable of inducing rapid diabetes in prediabetic NOD mice after only 2-weeks post-adoptive transfer in a manner partially dependent upon CD8+ T cell cytotoxicity (134–137). This evidence concerns the gene CD8A and diabetes mellitus.