A modified α-galactosyl ceramide for staining and stimulating natural killer T cells

CD1d presentation of α-galactosyl ceramides to natural killer T cells has been a focal point of the study of regulatory T cells. KRN7000, an α-galactosyl ceramide originally generated from structure activity studies of antitumor properties of marine sponge glycolipids, is currently the most commonly used agonist ligand and is used to stain NKT cells. However, this glycolipid suffers from poor solubility and availability. We have developed an α-galactosyl ceramide with improved solubility over KRN7000 that effectively stains NKT cells, both mouse and human, and stimulates cytokine release at low concentrations.