title: Novel O-linked methylated glycan antigens decorate secreted immunodominant glycoproteins from the intestinal nematode Heligmosomoides polygyrus.
abstract: Glycan molecules from helminth parasites have been associated with diverse biological functions ranging from interactions with neighbouring host cell populations to down-modulation of specific host immunity. Glycoproteins secreted by the intestinal nematode Heligmosomoides polygyrus are of particular interest as the excretory-secretory products (termed HES) of this parasite contain both heat-labile and heat-stable components with immunomodulatory effects. We used MALDI-TOF-MS and LC-MS/MS to analyse the repertoire of N- and O-linked glycans released from Heligmosomoides polygyrus excretory-secretory products by PNGase A and F, β-elimination and hydrazinolysis revealing a broad range of structures including novel methylhexose- and methylfucose-containing glycans. Monoclonal antibodies to two immunodominant glycans of H. polygyrus, previously designated Glycans A and B, were found to react by glycan array analysis to a methyl-hexose-rich fraction and to a sulphated LacDiNAc (LDN; GalNAcβ1-4GlcNAc) structure, respectively. We also analysed the glycan repertoire of a major glycoprotein in Heligmosomoides polygyrus excretory-secretory products, VAL-2, which contains many glycan structures present in Heligmosomoides polygyrus excretory-secretory products including Glycan A. However, it was found that this set of glycans is not responsible for the heat-stable immunomodulatory properties of Heligmosomoides polygyrus excretory-secretory products, as revealed by the inability of VAL-2 to inhibit allergic lung inflammation. Taken together, these studies reveal that H. polygyrus secretes a diverse range of antigenic glycoconjugates, and provides a framework to explore the biological and immunomodulatory roles they may play within the mammalian host.
authors.affiliation: Institute of Immunology and Infection Research, and Centre for Immunity, Infection and Evolution, School of Biological Sciences, Ashworth Laboratories, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK.
authors.forename: James P
authors.initials: JP
authors.lastname: Hewitson
authors.affiliation: Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands.
authors.forename: D Linh
authors.initials: DL
authors.lastname: Nguyen
authors.affiliation: Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands.
authors.forename: Angela
authors.initials: A
authors.lastname: van Diepen
authors.affiliation: Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands.
authors.forename: Cornelis H
authors.initials: CH
authors.lastname: Smit
authors.affiliation: Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands.
authors.forename: Carolien A
authors.initials: CA
authors.lastname: Koeleman
authors.affiliation: Institute of Immunology and Infection Research, and Centre for Immunity, Infection and Evolution, School of Biological Sciences, Ashworth Laboratories, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK.
authors.forename: Henry J
authors.initials: HJ
authors.lastname: McSorley
authors.affiliation: Institute of Immunology and Infection Research, and Centre for Immunity, Infection and Evolution, School of Biological Sciences, Ashworth Laboratories, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK.
authors.forename: Janice
authors.initials: J
authors.lastname: Murray
authors.affiliation: Institute of Immunology and Infection Research, and Centre for Immunity, Infection and Evolution, School of Biological Sciences, Ashworth Laboratories, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, UK.
authors.forename: Rick M
authors.initials: RM
authors.lastname: Maizels
authors.affiliation: Department of Parasitology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands. Electronic address: c.h.hokke@lumc.nl.
authors.forename: Cornelis H
authors.initials: CH
authors.lastname: Hokke
mesh_terms: D000818:Animals; D005260:Female; D006023:Glycoproteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D015801:Helminth Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D006801:Humans; D007422:Intestines / Q000737:chemistry / Q000276:immunology; D008297:Male; D008745:Methylation; D051379:Mice; D008807:Mice, Inbred BALB C; D009351:Nematospiroides dubius / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D011134:Polysaccharides / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D017206:Strongylida Infections / Q000276:immunology / Q000469:parasitology*
chemical_list: D006023:Glycoproteins; D015801:Helminth Proteins; D011134:Polysaccharides
keywords: Antibody; Carbohydrate; Excretory–secretory product; Heligmosomoides polygyrus; Mass spectrometry; Nematode