The involvement of iNKT cells in type 1 diabetes was first highlighted by the observations that qualitative and quantitative defects in iNKT cells exist in nonobese diabetic (NOD) mice,7 and later confirmed in both CD1d‐deficient NOD mice8, 9, 10 and by adoptive transfer experiments of iNKT cells, which accelerated and prevented type 1 diabetes, respectively.11, 12. Here, CD1D is linked to type 1 diabetes mellitus.