title: Highly purified mycobacterial phosphatidylinositol mannosides drive cell-mediated responses and activate NKT cells in cattle.
abstract: Mycobacterial lipids play an important role in the modulation of the immune response upon contact with the host. Using novel methods, we have isolated highly purified phosphatidylinositol mannoside (PIM) molecules (phosphatidylinositol dimannoside [PIM2], acylphosphatidylinositol dimannoside [AcPIM2], diacyl-phosphatidylinositol dimannoside [Ac2PIM2], acylphosphatidylinositol hexamannoside [AcPIM6], and diacylphosphatidylinositol hexamannoside [Ac2PIM6]) from virulent Mycobacterium tuberculosis to assess their potential to stimulate peripheral blood mononuclear cell (PBMC) responses in Mycobacterium bovis-infected cattle. Of these molecules, one (AcPIM6) induced significant levels of gamma interferon (IFN-γ) in bovine PBMCs. Three PIM molecules (AcPIM6, Ac2PIM2, and Ac2PIM6) were shown to drive significant proliferation in bovine PBMCs. AcPIM6 was subsequently used to phenotype the proliferating cells by flow cytometry. This analysis demonstrated that AcPIM6 was predominantly recognized by CD3(+) CD335(+) NKT cells. In conclusion, we have identified PIM lipid molecules that interact with bovine lymphocyte populations, and these lipids may be useful as future subunit vaccines or diagnostic reagents. Further, these data demonstrate, for the first time, lipid-specific NKT activation in cattle.
authors.affiliation: TB Research Group, Animal Health and Veterinary Laboratories Agency, New Haw, Addlestone, Surrey, United Kingdom chris.pirson@ahvla.gsi.gov.uk.
authors.forename: Chris
authors.initials: C
authors.lastname: Pirson
authors.affiliation: Division of Structural Biochemistry, Research Centre Borstel, Leibniz Centre for Medicine and Biosciences, Borstel, Germany.
authors.forename: Regina
authors.initials: R
authors.lastname: Engel
authors.affiliation: TB Research Group, Animal Health and Veterinary Laboratories Agency, New Haw, Addlestone, Surrey, United Kingdom.
authors.forename: Gareth J
authors.initials: GJ
authors.lastname: Jones
authors.affiliation: TB Research Group, Animal Health and Veterinary Laboratories Agency, New Haw, Addlestone, Surrey, United Kingdom.
authors.forename: Thomas
authors.initials: T
authors.lastname: Holder
authors.affiliation: Division of Structural Biochemistry, Research Centre Borstel, Leibniz Centre for Medicine and Biosciences, Borstel, Germany.
authors.forename: Otto
authors.initials: O
authors.lastname: Holst
authors.affiliation: TB Research Group, Animal Health and Veterinary Laboratories Agency, New Haw, Addlestone, Surrey, United Kingdom.
authors.forename: H Martin
authors.initials: HM
authors.lastname: Vordermeier
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000032:analysis; D002417:Cattle; D049109:Cell Proliferation; D005434:Flow Cytometry; D016130:Immunophenotyping; D007371:Interferon-gamma / Q000378:metabolism; D008213:Lymphocyte Activation; D008362:Mannosides / Q000276:immunology* / Q000302:isolation & purification; D009163:Mycobacterium bovis / Q000276:immunology*; D009169:Mycobacterium tuberculosis / Q000737:chemistry / Q000276:immunology*; D055611:Natural Killer T-Cells / Q000187:drug effects / Q000276:immunology*; D010716:Phosphatidylinositols / Q000276:immunology* / Q000302:isolation & purification; D014380:Tuberculosis, Bovine / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D008362:Mannosides; D010716:Phosphatidylinositols; D007371:Interferon-gamma