title: Beta-glycosphingolipids-mediated lipid raft alteration is associated with redistribution of NKT cells and increased intrahepatic CD8+ T lymphocyte trapping.
abstract: The aim of this study was to determine the effect of beta-glycosphingolipids on intra-hepatic natural killer T (NKT) lymphocyte regulatory function and on lymphocyte trapping via alteration of cell membrane lipid rafts. Immune-mediated colitis was induced by intracolonic instillation of trinitrobenzene sulfonic acid. Mice were treated with beta-lactosylceramide (LC), beta-glucosylceramide (GC), beta-galactosylceramide, ceramide, or a combination of both GC and LC (IGL), or solvent alone. Lipid rafts were investigated by fluorescence-activated cell sorting analysis of ganglioside-GM1 and fluorescence microscopy of structure. Administration of beta-glycosphingolipids resulted in an increased intrahepatic/peripheral NKT ratio, increased intrahepatic CD8+ lymphocyte trapping, decreased serum interferon-gamma (IFN-gamma) levels and decreased serum IFN-gamma/interleukin-10 ratio. Administration of GC, LC, or IGL significantly altered the levels of GM1, a key marker of lipid rafts, on NKT regulatory lymphocytes. The immune modulatory effect of beta-glycosphingolipids was associated with increased survival and significant alleviation of colitis as determined by improvement in both the macroscopic and microscopic scores. In conclusion, administration of beta-glycosphingolipids increased NKT regulatory lymphocyte redistribution and intrahepatic CD8(+) T lymphocyte trapping, resulting in alleviation of immune-mediated colitis. The effects of these naturally occurring compounds were associated with modification of the T lymphocyte lipid raft structure, which is a site for immune modulation.
authors.affiliation: Liver Unit, Department of Medicine, Hebrew University-Hadassah Medical Center, Jerusalem, Israel.
authors.forename: Gadi
authors.initials: G
authors.lastname: Lalazar
authors.forename: Ami
authors.initials: A
authors.lastname: Ben Ya'acov
authors.forename: Noa
authors.initials: N
authors.lastname: Eliakim-Raz
authors.forename: Dan M
authors.initials: DM
authors.lastname: Livovsky
authors.forename: Orit
authors.initials: O
authors.lastname: Pappo
authors.forename: Sarah
authors.initials: S
authors.lastname: Preston
authors.forename: Lidya
authors.initials: L
authors.lastname: Zolotarov
authors.forename: Yaron
authors.initials: Y
authors.lastname: Ilan
mesh_terms: D000818:Animals; D016516:CD4-CD8 Ratio; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D003092:Colitis / Q000139:chemically induced / Q000188:drug therapy / Q000276:immunology / Q000473:pathology; D016207:Cytokines / Q000097:blood; D006028:Glycosphingolipids / Q000502:physiology* / Q000627:therapeutic use; D007694:Killer Cells, Natural / Q000276:immunology*; D008099:Liver / Q000166:cytology; D008297:Male; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000502:physiology*; D014302:Trinitrobenzenesulfonic Acid
chemical_list: D016207:Cytokines; D006028:Glycosphingolipids; D014302:Trinitrobenzenesulfonic Acid