Indeed, the negative association between PB Tgfb1 expression at 10-week and 14-week insulitis scores is consistent with previous reports demonstrating that islet protection by Foxp3+ regulatory T cells (Treg) is controlled by TGF-β.24 Consistent with this, a high frequency of intra-islet Treg has been demonstrated for up to 3 weeks after diabetes onset in NOD mice.25 Also consistent with our data, treatment of NOD mice with TNF during the insulitic phase suppressed diabetes development.26 The gene discussed is TNF; the disease is diabetes mellitus.