title: Intracellular metabolite β-glucosylceramide is an endogenous Mincle ligand possessing immunostimulatory activity.
abstract: Sensing and reacting to tissue damage is a fundamental function of immune systems. Macrophage inducible C-type lectin (Mincle) is an activating C-type lectin receptor that senses damaged cells. Notably, Mincle also recognizes glycolipid ligands on pathogens. To elucidate endogenous glycolipids ligands derived from damaged cells, we fractionated supernatants from damaged cells and identified a lipophilic component that activates reporter cells expressing Mincle. Mass spectrometry and NMR spectroscopy identified the component structure as β-glucosylceramide (GlcCer), which is a ubiquitous intracellular metabolite. Synthetic β-GlcCer activated myeloid cells and induced production of inflammatory cytokines; this production was abrogated in Mincle-deficient cells. Sterile inflammation induced by excessive cell death in the thymus was exacerbated by hematopoietic-specific deletion of degrading enzyme of β-GlcCer (β-glucosylceramidase, GBA1). However, this enhanced inflammation was ameliorated in a Mincle-deficient background. GBA1-deficient dendritic cells (DCs) in which β-GlcCer accumulates triggered antigen-specific T-cell responses more efficiently than WT DCs, whereas these responses were compromised in DCs from GBA1 × Mincle double-deficient mice. These results suggest that β-GlcCer is an endogenous ligand for Mincle and possesses immunostimulatory activity.
authors.affiliation: Division of Molecular Immunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Nagata
authors.affiliation: Division of Metabolomics, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Izumi
authors.affiliation: Division of Molecular Immunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Eri
authors.initials: E
authors.lastname: Ishikawa
authors.affiliation: Division of Molecular Immunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Ryoko
authors.initials: R
authors.lastname: Kiyotake
authors.affiliation: Division of Molecular Immunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Rieko
authors.initials: R
authors.lastname: Doi
authors.affiliation: Division of Molecular Immunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Iwai
authors.affiliation: Division of Molecular Immunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Zakaria
authors.initials: Z
authors.lastname: Omahdi
authors.affiliation: Department of Biochemistry and Cell Biology, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Yamaji
authors.affiliation: Department of Natural Products Chemistry, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Miyamoto
authors.affiliation: Division of Metabolomics, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Bamba
authors.affiliation: Division of Molecular Immunology, Medical Institute of Bioregulation, Kyushu University, Fukuoka 812-8582, Japan; yamasaki@bioreg.kyushu-u.ac.jp.|Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Suita, 565-0871, Japan.|Division of Molecular Immunology, Medical Mycology Research Center, Chiba University, Chiba 260-8673, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Yamasaki
mesh_terms: D000818:Animals; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D005962:Glucosylceramidase / Q000502:physiology*; D005963:Glucosylceramides / Q000276:immunology* / Q000378:metabolism; D007114:Immunization; D007249:Inflammation / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D037181:Lectins, C-Type / Q000502:physiology*; D008024:Ligands; D008565:Membrane Proteins / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout
chemical_list: C113583:Clecsf8 protein, mouse; D016207:Cytokines; D005963:Glucosylceramides; D037181:Lectins, C-Type; D008024:Ligands; D008565:Membrane Proteins; D005962:Glucosylceramidase
keywords: C-type lectin receptors; Gaucher disease; ceramides; glycolipids; inflammation