title: High plasma membrane lipid order imaged at the immunological synapse periphery in live T cells.
abstract: Cholesterol- and glycosphingolipid-enriched membrane lipid microdomains, frequently called lipid rafts, are thought to play an important role in the spatial and temporal organization of immunological synapses. Higher ordering of lipid acyl chains was suggested for these entities and imaging of membrane order in living cells during activation can therefore help to understand the mechanisms responsible for the supramolecular organization of molecules involved in the activation of T cells. Here, we employ the phase-sensitive membrane dye di-4-ANEPPDHQ together with a variety of spectrally-resolved microscopy techniques, including 2-channel ratiometric TIRF microscopy and fluorescence lifetime imaging, to characterize membrane order at the T cell immunological synapse at high spatial and temporal resolution in live cells at physiological temperature. We find that higher membrane order resides at the immunological synapse periphery where proximal signalling through the immunoreceptors and accessory proteins in microclusters has previously been shown to take place. The observed spatial patterning of membrane order in the immunological synapse depends on active receptor signalling.
authors.affiliation: Chemical Biology Centre, Imperial College, London, UK.
authors.forename: Dylan M
authors.initials: DM
authors.lastname: Owen
authors.forename: Stephane
authors.initials: S
authors.lastname: Oddos
authors.forename: Sunil
authors.initials: S
authors.lastname: Kumar
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Davis
authors.forename: Mark A A
authors.initials: MA
authors.lastname: Neil
authors.forename: Paul M W
authors.initials: PM
authors.lastname: French
authors.forename: Michael L
authors.initials: ML
authors.lastname: Dustin
authors.forename: Anthony I
authors.initials: AI
authors.lastname: Magee
authors.forename: Marek
authors.initials: M
authors.lastname: Cebecauer
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D000938:Antigen-Presenting Cells / Q000378:metabolism; D006801:Humans; D054992:Immunological Synapses / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D019169:Jurkat Cells; D007653:Ketocholesterols / Q000737:chemistry / Q000378:metabolism; D008563:Membrane Lipids / Q000097:blood / Q000737:chemistry* / Q000276:immunology; D021962:Membrane Microdomains / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism; D008856:Microscopy, Fluorescence; D010713:Phosphatidylcholines / Q000737:chemistry / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology / Q000378:metabolism
chemical_list: D007653:Ketocholesterols; D008563:Membrane Lipids; D010713:Phosphatidylcholines; D015060:1,2-Dipalmitoylphosphatidylcholine; C017251:1,2-oleoylphosphatidylcholine; C003001:7-ketocholesterol