Development of a Schistosoma mansoni shotgun O-glycan microarray and application to the discovery of new antigenic schistosome glycan motifs. Issue 7 (June 2015)

• Record Type: Journal Article
• Authors: van Diepen, Angela; van der Plas, Arend-Jan; Kozak, Radoslaw P.; Royle, Louise; Dunne, David W.; Hokke, Cornelis H.
• Is Part Of: International journal for parasitology. Volume 45:Issue 7(2015)
• Page Start: 465
• Page End: 475
• Publication Date: 2015-06
• Subjects: Antibodies -- Glycan microarray -- O-glycans -- Schistosoma; Parasitology -- Periodicals; Parasitology -- Periodicals; Parasitologie -- Périodiques; Parasitology; Periodicals; Electronic journals; 571.999
• DOI: 10.1016/j.ijpara.2015.02.008
• Languages: English
• ISSNs: 0020-7519

Abstract

Graphical abstract: Highlights: The first known Schistosoma shotgun O-glycan microarray was generated. The modified hydrazinolysis method was applied to release naturally occurring O-glycans. Substantial anti-O-glycan responses were observed in Schistosoma -infected human sera. Novel antigenic O-glycan motifs have potential for use in diagnostics/vaccination. 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.