Regulatory B cells (Bregs) express high levels of CD1d, however, its  role  in Breg biology and contribution to iNKT cell function during inflammation remains unknown. I will present data showing how Bregs  “bridge" the innate and adaptive immune responses through the  generation of iNKT cells with suppressive function. Mice lacking CD1d-expressing B cells developed exacerbated arthritis compared to wild-type mice and failed to respond to α-galactosylceramide treatment. In these mice we show that CD1d lipid presentation by B cells is critical for the induction of iNKT cells that in turn down-regulate Th1 and Th17 adaptive immune responses and arthritis. We will discuss novel data showing how Bregs via lipid presentation, in an IL-10 independent manner, control and restrain excessive inflammation in autoimmunity.