title: Generation and characterization of β1,2-gluco-oligosaccharide probes from Brucella abortus cyclic β-glucan and their recognition by C-type lectins of the immune system.
abstract: The β1,2-glucans produced by bacteria are important in invasion, survival and immunomodulation in infected hosts be they mammals or plants. However, there has been a lack of information on proteins which recognize these molecules. This is partly due to the extremely limited availability of the sequence-defined oligosaccharides and derived probes for use in the study of their interactions. Here we have used the cyclic β1,2-glucan (CβG) of the bacterial pathogen Brucella abortus, after removal of succinyl side chains, to prepare linearized oligosaccharides which were used to generate microarrays. We describe optimized conditions for partial depolymerization of the cyclic glucan by acid hydrolysis and conversion of the β1,2-gluco-oligosaccharides, with degrees of polymerization 2-13, to neoglycolipids for the purpose of generating microarrays. By microarray analyses, we show that the C-type lectin receptor DC-SIGNR, like the closely related DC-SIGN we investigated earlier, binds to the β1,2-gluco-oligosaccharides, as does the soluble immune effector serum mannose-binding protein. Exploratory studies with DC-SIGN are suggestive of the recognition also of the intact CβG by this receptor. These findings open the way to unravelling mechanisms of immunomodulation mediated by β1,2-glucans in mammalian systems.
authors.affiliation: Glycosciences Laboratory, Department of Medicine, Imperial College London, London W12 0NN, UK.|Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
authors.forename: Hongtao
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Glycosciences Laboratory, Department of Medicine, Imperial College London, London W12 0NN, UK angelina.palma@fct.unl.pt w.chai@imperial.ac.uk.|UCIBIO-REQUIMTE, Department of Chemistry, Faculty of Science and Technology, NOVA Universidade de Lisboa, Caparica 2829-516, Portugal.
authors.forename: Angelina S
authors.initials: AS
authors.lastname: Palma
authors.affiliation: Glycosciences Laboratory, Department of Medicine, Imperial College London, London W12 0NN, UK.
authors.forename: Yibing
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Glycosciences Laboratory, Department of Medicine, Imperial College London, London W12 0NN, UK.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Childs
authors.affiliation: Glycosciences Laboratory, Department of Medicine, Imperial College London, London W12 0NN, UK.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: CSRI-UHCW, Walsgrave Campus, University of Warwick, Coventry CV2 2DX, UK.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Mitchell
authors.affiliation: Instituto de Investigaciones Biotecnológicas "Dr. Rodolfo A. Ugalde", Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín, San Martín, Buenos Aires 1650, Argentina.
authors.forename: Leticia S
authors.initials: LS
authors.lastname: Guidolin
authors.affiliation: SCIENION AG, Volmerstrasse 7b, Berlin 12489, Germany.
authors.forename: Wilfried
authors.initials: W
authors.lastname: Weigel
authors.affiliation: Glycosciences Laboratory, Department of Medicine, Imperial College London, London W12 0NN, UK.
authors.forename: Barbara
authors.initials: B
authors.lastname: Mulloy
authors.affiliation: Instituto de Investigaciones Biotecnológicas "Dr. Rodolfo A. Ugalde", Instituto Tecnológico de Chascomús (IIB-INTECH), Universidad Nacional de San Martín, San Martín, Buenos Aires 1650, Argentina.
authors.forename: Andrés E
authors.initials: AE
authors.lastname: Ciocchini
authors.affiliation: Glycosciences Laboratory, Department of Medicine, Imperial College London, London W12 0NN, UK.
authors.forename: Ten
authors.initials: T
authors.lastname: Feizi
authors.affiliation: Glycosciences Laboratory, Department of Medicine, Imperial College London, London W12 0NN, UK angelina.palma@fct.unl.pt w.chai@imperial.ac.uk.
authors.forename: Wengang
authors.initials: W
authors.lastname: Chai
mesh_terms: D002003:Brucella abortus / Q000737:chemistry* / Q000276:immunology; D007107:Immune System / Q000276:immunology; D037181:Lectins, C-Type / Q000737:chemistry* / Q000276:immunology*; D046228:Microarray Analysis; D015335:Molecular Probes / Q000032:analysis* / Q000276:immunology*; D009844:Oligosaccharides / Q000032:analysis* / Q000096:biosynthesis* / Q000276:immunology
chemical_list: D037181:Lectins, C-Type; D015335:Molecular Probes; D009844:Oligosaccharides
keywords: C-type lectins; carbohydrate microarray; glucan recognition; neoglycolipids; β1,2-glucan