title: Development of a Schistosoma mansoni shotgun O-glycan microarray and application to the discovery of new antigenic schistosome glycan motifs.
abstract: Upon infection with Schistosoma, antibody responses are mounted that are largely directed against glycans. Over the last few years significant progress has been made in characterising the antigenic properties of N-glycans of Schistosoma mansoni. Despite also being abundantly expressed by schistosomes, much less is understood about O-glycans and antibody responses to these have not yet been systematically analysed. Antibody binding to schistosome glycans can be analysed efficiently and quantitatively using glycan microarrays, but O-glycan array construction and exploration is lagging behind because no universal O-glycanase is available, and release of O-glycans has been dependent on chemical methods. Recently, a modified hydrazinolysis method has been developed that allows the release of O-glycans with free reducing termini and limited degradation, and we applied this method to obtain O-glycans from different S. mansoni life stages. Two-dimensional HPLC separation of 2-aminobenzoic acid-labelled O-glycans generated 362 O-glycan-containing fractions that were printed on an epoxide-modified glass slide, thereby generating the first shotgun O-glycan microarray containing naturally occurring schistosome O-glycans. Monoclonal antibodies and mass spectrometry showed that the O-glycan microarray contains well-known antigenic glycan motifs as well as numerous other, potentially novel, antibody targets. Incubations of the microarrays with sera from Schistosoma-infected humans showed substantial antibody responses to O-glycans in addition to those observed to the previously investigated N- and glycosphingolipid glycans. This underlines the importance of the inclusion of these often schistosome-specific O-glycans in glycan antigen studies and indicates that O-glycans contain novel antigenic motifs that have potential for use in diagnostic methods and studies aiming at the discovery of vaccine targets.
authors.affiliation: Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands. Electronic address: a.van_diepen@lumc.nl.
authors.forename: Angela
authors.initials: A
authors.lastname: van Diepen
authors.affiliation: Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Arend-Jan
authors.initials: AJ
authors.lastname: van der Plas
authors.affiliation: Ludger Ltd., Culham Science Centre, Oxfordshire OX14 3EB, UK.
authors.forename: Radoslaw P
authors.initials: RP
authors.lastname: Kozak
authors.affiliation: Ludger Ltd., Culham Science Centre, Oxfordshire OX14 3EB, UK.
authors.forename: Louise
authors.initials: L
authors.lastname: Royle
authors.affiliation: Department of Pathology, University of Cambridge, UK.
authors.forename: David W
authors.initials: DW
authors.lastname: Dunne
authors.affiliation: Department of Parasitology, Center of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Cornelis H
authors.initials: CH
authors.lastname: Hokke
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D000947:Antigens, Helminth / Q000737:chemistry / Q000378:metabolism*; D051379:Mice; D046228:Microarray Analysis; D011134:Polysaccharides / Q000378:metabolism*; D011485:Protein Binding; D012550:Schistosoma mansoni / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D000947:Antigens, Helminth; D011134:Polysaccharides
keywords: Antibodies; Glycan microarray; O-glycans; Schistosoma