CD1D and infection: In the latter regard, it has been reported that maturation of hepatic DC were dependent upon the activation of NKT cells through either administration of alpha-galactosylceramide (αGalCer) or through infection with MCMV [11]; however, mature DC, based upon co-stimulatory expression, were still observed following IL-12 administration to CD1d knock-out mice, which developmentally lack NKT cells (our unpublished observations).