Immunostimulatory activities of monoglycosylated α-d-pyranosylceramides Original Research Article

We compared the immunostimulatory effects of chemically synthesized α-galactosylceramides (α-GalCers), α-glucosylceramides (α-GluCers), 6″-monoglycosylated α-GalCer and 6″- or 4″-monoglycosylated α-GluCer and made the following observations: (1) the length of the fatty acid side chain in the ceramide portions greatly affects the immunostimulatory effects of α-GalCers and α-GluCers; (2) the configuration of the 4″-hydroxyl group of the inner pyranose moiety plays an important role in the immunostimulatory effects of monoglycosylated α-d-pyranosylceramides; (3) the free 4″-hydroxyl group of the inner pyranose of monoglycosylated α-d-pyranosylceramides plays a more important role in their immunostimulatory effects than the free 6″-hydroxyl group.