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Eriksson L, Johannesen TB, Stenmark B, Jacobsson S, Säll O, Hedberg ST, Fredlund H, Stegger M, Mölling P. Genetic variants linked to the phenotypic outcome of invasive disease and carriage of Neisseria meningitidis. Microb Genom 2023; 9:001124. [PMID: 37874326 PMCID: PMC10634450 DOI: 10.1099/mgen.0.001124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 10/10/2023] [Indexed: 10/25/2023] Open
Abstract
Neisseria meningitidis can be a human commensal in the upper respiratory tract but is also capable of causing invasive diseases such as meningococcal meningitis and septicaemia. No specific genetic markers have been detected to distinguish carriage from disease isolates. The aim here was to find genetic traits that could be linked to phenotypic outcomes associated with carriage versus invasive N. meningitidis disease through a bacterial genome-wide association study (GWAS). In this study, invasive N. meningitidis isolates collected in Sweden (n=103) and carriage isolates collected at Örebro University, Sweden (n=213) 2018-2019 were analysed. The GWAS analysis, treeWAS, was applied to single-nucleotide polymorphisms (SNPs), genes and k-mers. One gene and one non-synonymous SNP were associated with invasive disease and seven genes and one non-synonymous SNP were associated with carriage isolates. The gene associated with invasive disease encodes a phage transposase (NEIS1048), and the associated invasive SNP glmU S373C encodes the enzyme N-acetylglucosamine 1-phosphate (GlcNAC 1-P) uridyltransferase. Of the genes associated with carriage isolates, a gene variant of porB encoding PorB class 3, the genes pilE/pilS and tspB have known functions. The SNP associated with carriage was fkbp D33N, encoding a FK506-binding protein (FKBP). K-mers from PilS, tbpB and tspB were found to be associated with carriage, while k-mers from mtrD and tbpA were associated with invasiveness. In the genes fkbp, glmU, PilC and pilE, k-mers were found that were associated with both carriage and invasive isolates, indicating that specific variations within these genes could play a role in invasiveness. The data presented here highlight genetic traits that are significantly associated with invasive or carriage N. meningitidis across the species population. These traits could prove essential to our understanding of the pathogenicity of N. meningitidis and could help to identify future vaccine targets.
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Affiliation(s)
- Lorraine Eriksson
- Department of Laboratory Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Thor Bech Johannesen
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Bianca Stenmark
- Department of Laboratory Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Susanne Jacobsson
- Department of Laboratory Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Olof Säll
- Department of Infectious Diseases, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Sara Thulin Hedberg
- Department of Laboratory Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Hans Fredlund
- Department of Laboratory Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Marc Stegger
- Department of Laboratory Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Paula Mölling
- Department of Laboratory Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
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de Jong H, Wösten MMSM, Wennekes T. Sweet impersonators: Molecular mimicry of host glycans by bacteria. Glycobiology 2022; 32:11-22. [PMID: 34939094 PMCID: PMC8881735 DOI: 10.1093/glycob/cwab104] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 09/03/2021] [Accepted: 09/28/2021] [Indexed: 12/02/2022] Open
Abstract
All bacteria display surface-exposed glycans that can play an important role in their interaction with the host and in select cases mimic the glycans found on host cells, an event called molecular or glycan mimicry. In this review, we highlight the key bacteria that display human glycan mimicry and provide an overview of the involved glycan structures. We also discuss the general trends and outstanding questions associated with human glycan mimicry by bacteria. Finally, we provide an overview of several techniques that have emerged from the discipline of chemical glycobiology, which can aid in the study of the composition, variability, interaction and functional role of these mimicking glycans.
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Affiliation(s)
- Hanna de Jong
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, and Bijvoet Center for Biomedical Research, Utrecht University, Universiteitsweg 99, Utrecht 3584 CG, The Netherlands
- Department of Biomolecular Health Sciences, Utrecht University, Yalelaan 1, Utrecht 3584 CL, The Netherlands
| | - Marc M S M Wösten
- Department of Biomolecular Health Sciences, Utrecht University, Yalelaan 1, Utrecht 3584 CL, The Netherlands
| | - Tom Wennekes
- Department of Chemical Biology and Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, and Bijvoet Center for Biomedical Research, Utrecht University, Universiteitsweg 99, Utrecht 3584 CG, The Netherlands
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John CM, Phillips NJ, Stein DC, Jarvis GA. Innate immune response to lipooligosaccharide: pivotal regulator of the pathobiology of invasive Neisseria meningitidis infections. Pathog Dis 2017; 75:3569603. [PMID: 28423169 DOI: 10.1093/femspd/ftx030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 03/11/2017] [Indexed: 01/05/2023] Open
Abstract
Infections due to Neisseria meningitidis afflict more than one million people worldwide annually and cause death or disability in many survivors. The clinical course of invasive infections has been well studied, but our understanding of the cause of differences in patient outcomes has been limited because these are dependent on multiple factors including the response of the host, characteristics of the bacteria and interactions between the host and the bacteria. The meningococcus is a highly inflammatory organism, and the lipooligosaccharide (LOS) on the outer membrane is the most potent inflammatory molecule it expresses due to the interactions of the lipid A moiety of LOS with receptors of the innate immune system. We previously reported that increased phosphorylation of hexaacylated neisserial lipid A is correlated with greater inflammatory potential. Here we postulate that variability in lipid A phosphorylation can tip the balance of innate immune responses towards homeostatic tolerance or proinflammatory signaling that affects adaptive immune responses, causing disease with meningitis only, or septicemia with or without meningitis, respectively. Furthermore, we propose that studies of the relationship between bacterial virulence and gene expression should consider whether genetic variation could affect properties of biosynthetic enzymes resulting in LOS structural differences that alter disease pathobiology.
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Affiliation(s)
- Constance M John
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA 94121, USA.,Department of Laboratory Medicine, University of California, San Francisco, CA 94143, USA
| | - Nancy J Phillips
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA 94143, USA
| | - Daniel C Stein
- University of Maryland, Department of Cell Biology and Molecular Genetics, College Park, MD 20742 USA
| | - Gary A Jarvis
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA 94121, USA.,Department of Laboratory Medicine, University of California, San Francisco, CA 94143, USA
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John CM, Phillips NJ, Din R, Liu M, Rosenqvist E, Høiby EA, Stein DC, Jarvis GA. Lipooligosaccharide Structures of Invasive and Carrier Isolates of Neisseria meningitidis Are Correlated with Pathogenicity and Carriage. J Biol Chem 2015; 291:3224-38. [PMID: 26655715 DOI: 10.1074/jbc.m115.666214] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Indexed: 11/06/2022] Open
Abstract
The degree of phosphorylation and phosphoethanolaminylation of lipid A on neisserial lipooligosaccharide (LOS), a major cell-surface antigen, can be correlated with inflammatory potential and the ability to induce immune tolerance in vitro. On the oligosaccharide of the LOS, the presence of phosphoethanolamine and sialic acid substituents can be correlated with in vitro serum resistance. In this study, we analyzed the structure of the LOS from 40 invasive isolates and 25 isolates from carriers of Neisseria meningitidis without disease. Invasive strains were classified as groups 1-3 that caused meningitis, septicemia without meningitis, and septicemia with meningitis, respectively. Intact LOS was analyzed by high resolution matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Prominent peaks for lipid A fragment ions with three phosphates and one phosphoethanolamine were detected in all LOS analyzed. LOS from groups 2 and 3 had less abundant ions for highly phosphorylated lipid A forms and induced less TNF-α in THP-1 monocytic cells compared with LOS from group 1. Lipid A from all invasive strains was hexaacylated, whereas lipid A of 6/25 carrier strains was pentaacylated. There were fewer O-acetyl groups and more phosphoethanolamine and sialic acid substitutions on the oligosaccharide from invasive compared with carrier isolates. Bioinformatic and genomic analysis of LOS biosynthetic genes indicated significant skewing to specific alleles, dependent on the disease outcome. Our results suggest that variable LOS structures have multifaceted effects on homeostatic innate immune responses that have critical impact on the pathophysiology of meningococcal infections.
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Affiliation(s)
- Constance M John
- From the Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California 94121, the Departments of Laboratory Medicine and
| | | | - Richard Din
- From the Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California 94121
| | - Mingfeng Liu
- From the Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California 94121, the Departments of Laboratory Medicine and
| | - Einar Rosenqvist
- the Norwegian Institute of Public Health, P. O. Box 4404, Nydalen, 0403 Oslo, Norway, and
| | - E Arne Høiby
- the Norwegian Institute of Public Health, P. O. Box 4404, Nydalen, 0403 Oslo, Norway, and
| | - Daniel C Stein
- the Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland 20742
| | - Gary A Jarvis
- From the Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California 94121, the Departments of Laboratory Medicine and
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Mistretta N, Seguin D, Thiébaud J, Vialle S, Blanc F, Brossaud M, Talaga P, Norheim G, Moreau M, Rokbi B. Genetic and structural characterization of L11 lipooligosaccharide from Neisseria meningitidis serogroup A strains. J Biol Chem 2010; 285:19874-83. [PMID: 20421293 DOI: 10.1074/jbc.m110.100636] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The lipooligosaccharide (LOS) of immunotype L11 is unique within serogroup A meningococci. In order to resolve its molecular structure, we conducted LOS genotyping by PCR analysis of genes responsible for alpha-chain sugar addition (lgtA, -B, -C, -E, -H, and -F) and inner core substituents (lgtG, lpt-3, and lpt-6). For this study, we selected seven strains belonging to subgroup III, a major clonal complex responsible for meningococcal meningitis epidemics in Africa. In addition, we sequenced the homopolymeric tract regions of three phase-variable genes (lgtA, lgtG, and lot-3) to predict gene functionality. The fine structure of the L11 LOS of each strain was determined using composition and glycosyl linkage analyses, NMR, and mass spectrometry. The masses of the dephosphorylated oligosaccharides were consistent with an oligosaccharide composed of two hexoses, one N-acetyl-hexosamine, two heptoses, and one KDO, as proposed previously. The molar composition of LOS showed two glucose residues to be present, in agreement with lgtH sequence prediction. Despite phosphoethanolaminetransferase genes lpt-3 and lpt-6 being present in all seven Neisseria meningitidis strains, phosphoethanolamine (PEtn) was found at both O-3 and O-6 of HepII among the three ST-5 strains, whereas among the four ST-7 strains, only one PEtn was found and located at O-3 of the HepII. The L11 LOS was found to be O-acetylated, as was indicated by the presence of the lot-3 gene being in-frame in all of the seven N. meningitidis strains. To our knowledge, these studies represent the first full genetic and structural characterization of the L11 LOS of N. meningitidis. These investigations also suggest the presence of further regulatory mechanisms affecting LOS structure microheterogeneity in N. meningitidis related to PEtn decoration of the inner core.
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Affiliation(s)
- Noëlle Mistretta
- Sanofi Pasteur, 1541 Avenue Marcel Mérieux, 69280 Marcy l'Etoile, France
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Tsai CM, Jankowska-Stephens E, Mizanur RM, Cipollo JF. The Fine Structure of Neisseria meningitidis Lipooligosaccharide from the M986 Strain and Three of Its Variants. J Biol Chem 2009; 284:4616-25. [DOI: 10.1074/jbc.m808209200] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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John CM, Liu M, Jarvis GA. Profiles of structural heterogeneity in native lipooligosaccharides of Neisseria and cytokine induction. J Lipid Res 2008; 50:424-438. [PMID: 18832773 DOI: 10.1194/jlr.m800184-jlr200] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fine differences in the phosphorylation and acylation of lipooligosaccharide (LOS) from Neisseria species are thought to profoundly influence the virulence of the organisms and the innate immune responses of the host, such as signaling through toll-like receptor 4 (TLR4) and triggering receptor expressed on myeloid cells (TREM). MALDI time-of-flight (TOF) mass spectrometry was used to characterize heterogeneity in the native LOS from Neisseria gonorrheae and N. meningitidis. A sample preparation methodology previously reported for Escherichia coli lipopolysaccharide (LPS) employing deposition of untreated LOS on a thin layer of a film composed of 2,4,6-trihydroxyacetophenone and nitrocellulose was used. Prominent peaks were observed corresponding to molecular ions and to fragment ions primarily formed by cleavage between the 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo) and the lipid A (LA). Analyses of these data and comparison with spectra of the corresponding O-deacylated or hydrogen fluoride-treated LOS enabled the detection of novel species that apparently differed by the expression of up to three phosphates with one or more phosphoethanolamine (PEA) groups on the LA. We found that the heterogeneity profile of acylation and phosphorylation correlates with the induction of proinflammatory cytokines in THP-1 monocytic cells. This methodology enabled us to rapidly profile components of structural variants of native LOS that are of importance biologically.
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Affiliation(s)
- Constance M John
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA, 94121
| | - Mingfeng Liu
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA, 94121
| | - Gary A Jarvis
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA, 94121; Department of Laboratory Medicine, University of California, San Francisco, CA 94143.
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Packiam M, Shell DM, Liu SV, Liu YB, McGee DJ, Srivastava R, Seal S, Rest RF. Differential expression and transcriptional analysis of the alpha-2,3-sialyltransferase gene in pathogenic Neisseria spp. Infect Immun 2006; 74:2637-50. [PMID: 16622200 PMCID: PMC1459705 DOI: 10.1128/iai.74.5.2637-2650.2006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Alpha-2,3-sialyltransferase (Lst) is expressed on the outer membrane of Neisseria gonorrhoeae and Neisseria meningitidis and sialylates surface lipooligosaccharide (LOS), facilitating resistance to complement-mediated killing. The enzyme is constitutively expressed from a single gene (lst) and does not undergo antigenic or phase variation. We observed that Triton X-100 extracts of N. gonorrhoeae strain F62 contain about fivefold more sialyltransferase (Stase) activity than extracts of N. meningitidis strain MC58 [symbol: see text]3 a serogroup B acapsulate mutant. We confirmed and expanded upon this observation by showing that extracts of 16 random N. gonorrhoeae isolates contain various amounts of Stase activity, but, on average, 2.2-fold-more Stase activity than extracts of 16 N. meningitidis clinical isolates, representing several serogroups and nongroupable strains. Northern and real-time reverse transcription-PCR analysis of lst transcript levels in N. gonorrhoeae and N. meningitidis revealed that N. gonorrhoeae strains express more lst transcript than N. meningitidis strains. Although transcript levels correlate with average Stase activity observed in the two species, there was not a direct correlation between lst transcript levels and Stase activity among individual isolates of each species. Comparison of lst upstream (5'lst) regions of N. gonorrhoeae and N. meningitidis revealed striking sequence differences characteristic of the two pathogens. N. gonorrhoeae 5'lst regions possess 30-bp and 13-bp elements present as single elements or as tandem repeats that exist only as single elements in the 5'lst regions of N. meningitidis isolates. In addition, the 5'lst regions of N. meningitidis strains have 105-bp transposon-like Correia elements which are absent in N. gonorrhoeae. Chromosomal N. gonorrhoeae 5'lst::lacZ translational fusions expressed 4.75 +/- 0.09-fold (n = 4) higher beta-galactosidase (beta-gal) activity than N. meningitidis 5'lst::lacZ fusions in a host-independent manner, indicating differential expression is governed at least in part by sequence variations in the 5'lst regions. Reporter fusion assays and promoter-mapping analysis revealed that N. gonorrhoeae and N. meningitidis use different promoters with different strengths to transcribe lst. In N. gonorrhoeae, a strong sigma 70 promoter 80 bp upstream of the translational start site is used to transcribe lst, whereas this promoter is inactive in N. meningitidis. In N. meningitidis, a weak sigma 70 promoter at the 3' terminus of a 105-bp Correia repeat-enclosed element 99 bp upstream of the translational start site is used to transcribe lst. We conclude that differential Stase expression between N. gonorrhoeae and N. meningitidis is due at least in part to differential lst gene transcription.
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Affiliation(s)
- Mathanraj Packiam
- Department of Microbiology and Immunology, Drexel University College of Medicine, 2900 Queen Lane, Philadelphia, PA 19129, USA
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Zhu P, Boykins RA, Tsai CM. Genetic and functional analyses of the lgtH gene, a member of the β-1,4-galactosyltransferase gene family in the genus Neisseria. Microbiology (Reading) 2006; 152:123-134. [PMID: 16385122 DOI: 10.1099/mic.0.28327-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Lipooligosaccharide (LOS) is a major virulence factor of the pathogenic Neisseria. Three galactosyltransferase genes, lgtB, lgtE and lgtH, responsible for the biosynthesis of LOS oligosaccharide chains, were analysed in five Neisseria species. The function of lgtH in Neisseria meningitidis 6275 was determined by mutagenesis and chemical characterization of the parent and mutant LOS chains. The chemical characterization included SDS-PAGE, immunoblot, hexose and mass spectrometry analyses. Compared with the parent LOS, the mutant LOS lacked galactose, and its oligosaccharide decreased by three or four sugar units in matrix-assisted laser desorption ionization (MALDI)-MS analysis. The results show that lgtH encodes a β-1,4-galactosyltransferase, and that the glucose moiety linked to heptose (Hep) in the α chain is the acceptor site in the biosynthesis of Neisseria LOS. To understand the sequence diversity and relationships of lgtB, lgtE and lgtH, the entire lgt-1 locus was further sequenced in three N. meningitidis strains and three commensal Neisseria strains, and compared with the previously reported lgt genes from Neisseria species. Comparison of the protein sequences of the three enzymes LgtB, LgtE and LgtH showed a conserved N-terminal region, and a highly variable C-terminal region, suggesting functional constraint for substrate and acceptor specificity, respectively. The analyses of allelic variation and evolution of 23 lgtB, 12 lgtE and 14 lgtH sequences revealed a distinct evolutionary history of these genes in Neisseria. For example, the splits graph of lgtE displayed a network evolution, indicating frequent DNA recombination, whereas splits graphs of lgtB and lgtH displayed star-tree-like evolution, indicating the accumulation of point mutations. The data presented here represent examples of the evolution and variation of prokaryotic glycosyltransferase gene families. These imply the existence of multiple enzyme isoforms for biosynthesis of a great diversity of oligosaccharides in nature.
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Affiliation(s)
- Peixuan Zhu
- Division of Bacterial, Parasitic and Allergenic Products, Center for Biologics Evaluation and Research, FDA, 8800 Rockville Pike, Bethesda, MD 20892, USA
| | - Robert A Boykins
- Division of Bacterial, Parasitic and Allergenic Products, Center for Biologics Evaluation and Research, FDA, 8800 Rockville Pike, Bethesda, MD 20892, USA
| | - Chao-Ming Tsai
- Division of Bacterial, Parasitic and Allergenic Products, Center for Biologics Evaluation and Research, FDA, 8800 Rockville Pike, Bethesda, MD 20892, USA
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Jones C, Virji M, Crocker PR. Recognition of sialylated meningococcal lipopolysaccharide by siglecs expressed on myeloid cells leads to enhanced bacterial uptake. Mol Microbiol 2003; 49:1213-25. [PMID: 12940982 DOI: 10.1046/j.1365-2958.2003.03634.x] [Citation(s) in RCA: 167] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Sialic acid-binding immunoglobulin-like lectins (siglecs) are expressed predominantly in the haemopoietic and immune systems and exhibit specificities for both the linkage and the nature of sialic acids in N-glycans, O-glycans and glycolipids. Several siglecs, including sialoadhesin (Sn, siglec-1) and siglec-5, bind to NeuAcalpha2,3Gal, a terminal capping structure that can also be displayed on the lipopolysaccharide (LPS) of Neisseria meningitidis (Nm). In the present study, we examined the potential of siglecs expressed on cells of the immune system to function as receptors for sialylated Nm. We used sialylated and non-sialylated LPS derivatives of two serogroups (A and B) of Nm in this study. Using recombinant chimeric soluble receptors, siglec-transfected cell lines and macrophages from wild-type and Sn-deficient mice, we observed that sialylated but not non-sialylated variants of either genetic background were specifically recognized by Sn and siglec-5, whereas other siglecs examined were ineffective. In addition, macrophages expressing Sn, as well as transfectants expressing Sn or siglec-5, bound and phagocytosed sialylated bacteria in a siglec- and sialic acid-dependent manner. This study demonstrates that Nm LPS sialylation can lead to increased bacterial susceptibility to phagocytic uptake, a phenomenon in direct contrast to previously reported protective effects of LPS sialylation.
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Affiliation(s)
- Claire Jones
- The Wellcome Trust Biocentre, School of Life Sciences, University of Dundee, Dundee, UK
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Pridmore AC, Jarvis GA, John CM, Jack DL, Dower SK, Read RC. Activation of toll-like receptor 2 (TLR2) and TLR4/MD2 by Neisseria is independent of capsule and lipooligosaccharide (LOS) sialylation but varies widely among LOS from different strains. Infect Immun 2003; 71:3901-8. [PMID: 12819075 PMCID: PMC161978 DOI: 10.1128/iai.71.7.3901-3908.2003] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lipooligosaccharide (LOS) structure and capsular polysaccharide of Neisseria meningitidis each greatly influence the virulence of the organism and the quality of host innate immune responses. In this study, we found that production of the proinflammatory cytokine tumor necrosis factor (TNF) by a human monocyte-derived cell line (THP-1) exposed to strains of N. meningitidis lacking capsule and/or with truncated LOS was similar to that elicited by the isogenic wild-type strain. These mutants also exhibited no difference in induction of the interleukin-8 (IL-8) promoter in a transfected HeLa cell system of Toll-like receptor 2 (TLR2) and TLR4/MD2 signaling. However, purified LOS from diverse strains of Neisseria (both N. meningitidis and N. gonorrhoeae) caused widely variant levels of IL-8 promoter induction in cells expressing MD2 that correlated with the production of TNF from THP-1 cells. These data suggest that although modification of the oligosaccharide chain of LOS and/or absence of capsule do not affect cell signaling mediated by TLR4/MD2, fine-structural differences in the LOS do influence signaling through TLR4/MD2 and, through this pathway, influence some of the proinflammatory responses elicited by Neisseria.
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Affiliation(s)
- Alison C Pridmore
- Division of Genomic Medicine, Royal Hallamshire Hospital, University of Sheffield, Sheffield S10 2RX, United Kingdom
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