α-Galactosylceramide (α-GalCer) or the common name of KRN7000 is an agelasphin derivative developed by Kirin Brewery Co., Ltd., is a biological response modifier (BRM). Agelasphins was isolated from an extract of the Okinawan marine sponge Agelas mauritianus. The Alpha-GalCer structure consist of a galactose combined with a ceramide in an alpha-configuration.
KRN7000 is no longer extracted from the native source, but chemically synthesized. Alpha-GalCer is a specific ligand for human and mouse natural killer T (NKT) cells and KRN7000 exhibits potent anti-tumor activity with murine in vivo experiments including subcutaneous implanted model and metastatic models in the liver and lung. In the liver metastatic models, treatment with KRN7000 suppressed the growth of tumors and prolonged the survival term of the tumor-bearing mice. KRN7000 has been reported to show various immunological effects in infectious diseases, autoimmune disease and graft verse host disease in mice.
KRN7000 chemical properties:
Molecular Formula: C50H99NO9
Melting point: 189-190°C
Appearance: Off-white powder
Solubility: Insoluble in water, methanol, ethanol or
other organic solvents, very slightly soluble in
tetrahydrofuran, slightly soluble in pyridine
KRN7000 chemical structure:
Click here to learn how to draw Alpha-GalCer molecule. This weblink is a short animation about the chemical synthesis of Alpha-GalCer.
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