title: Crohn's disease alters MHC-rafts in CD4+ T-cells.
abstract: Clusters of MHCI, ICAM-1, CD44, CD59, IL-2R, and IL-15R molecules have been studied on the surface of CD4(+) T-cells from peripheral blood and lymph nodes of patients in Crohn's disease and healthy individuals as controls by using a dual-laser flow cytometric fluorescence resonance energy transfer (FRET) technique and fluorescently stained Fabs. When cells from patients in Crohn's disease are compared to those of controls, the surface expression level for the MHCI reduced by ∼45%, for CD44 enhanced by ∼100%, and for IL-2Rα, IL-15Rα, and common γ(c) enhanced by ∼50%, ∼70%, and ∼130%, respectively. Efficiencies of FRET monitoring homoassociation for the MHCI and CD44 reduced, that for IL-2Rα enhanced. While efficiencies of FRET monitoring the association of γ(c) and ICAM-1 with the MHCI reduced, those monitoring association of IL-2/15Rα, CD44, and CD59 with MHCI enhanced. Efficiencies of FRET measured between the MHCI and IL-2Rα, IL-15Rα differently enhanced to the advantage of IL-15Rα, the one measured between γ(c) and IL-2Rα reduced, suggesting modulations in the strength of interaction of MHCI with IL-2R, IL-15R, and γ(c). The increases in density of surface bound cTx and in the associations of the receptors with the G(M1)-ganglioside lipid molecules suggest stronger lipid raft interactions of the receptors. The observed alterations of MHC-rafts in Crohn's disease--summarized in models of receptor patterns of diseased and control cells--may have functional consequences regarding signaling by the raft components.
authors: Department of Surgery, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary.
authors: László
authors: L
authors: Damjanovich
authors: Julianna
authors: J
authors: Volkó
authors: Attila
authors: A
authors: Forgács
authors: Werner
authors: W
authors: Hohenberger
authors: László
authors: L
authors: Bene
mesh_terms: D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000473:pathology; D018957:CD59 Antigens / Q000378:metabolism; D016022:Case-Control Studies; D002469:Cell Separation; D003424:Crohn Disease / Q000276:immunology* / Q000473:pathology*; D015536:Down-Regulation; D005434:Flow Cytometry; D031541:Fluorescence Resonance Energy Transfer; D005677:G(M1) Ganglioside / Q000378:metabolism; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism; D007140:Immunoglobulin Fab Fragments / Q000276:immunology; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D019409:Interleukin-15 / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D008285:Major Histocompatibility Complex / Q000276:immunology*; D021962:Membrane Microdomains / Q000276:immunology*; D011485:Protein Binding; D021122:Protein Subunits / Q000378:metabolism; D018123:Receptors, Interleukin / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D018957:CD59 Antigens; D018960:Hyaluronan Receptors; D007140:Immunoglobulin Fab Fragments; D019409:Interleukin-15; D007376:Interleukin-2; D021122:Protein Subunits; D018123:Receptors, Interleukin; D018799:Intercellular Adhesion Molecule-1; D005677:G(M1) Ganglioside