alpha-Galactosylceramide (alpha-GalCer) is a synthetic glycolipid with antitumorial and immunostimulatory. alpha-Galactosylceramide is a very potent NKT cell agonist and binds effectively to CD1d. The complex of alpha-Galactosylceramide plus CD1d binds the NKT cell TCR (T cell antigen receptor)[1][2][3][4].