However, these chemokine receptors are responsible for the recruitment of both diabetogenic and protective cells as revealed by the reduced incidence of diabetes observed in the CCR2−/− NOD mice and the accelerated incidence in the CXCR3−/− or the CCR5−/− NOD mice (Solomon et al, 2010; Yamada et al, 2012). This evidence concerns the gene CCR2 and diabetes mellitus.