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Cardenas AJ, Thomas KS, Broden MW, Ferraro NJ, Pires MM, John CM, Jarvis GA, Criss AK. Neisseria gonorrhoeae scavenges host sialic acid for Siglec-mediated, complement-independent suppression of neutrophil activation. mBio 2024; 15:e0011924. [PMID: 38587424 PMCID: PMC11078009 DOI: 10.1128/mbio.00119-24] [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: 01/14/2024] [Accepted: 03/12/2024] [Indexed: 04/09/2024] Open
Abstract
Gonorrhea, caused by the bacterium Neisseria gonorrhoeae (Gc), is characterized by neutrophilic influx to infection sites. Gc has developed mechanisms to resist killing by neutrophils that include modifications to its surface lipooligosaccharide (LOS). One such LOS modification is sialylation: Gc sialylates its terminal LOS sugars with cytidine-5'-monophosphate-N-acetylneuraminic acid, which is scavenged from the host using LOS sialyltransferase (Lst) since Gc cannot make its sialic acid. Sialylation enables sensitive strains of Gc to resist complement-mediated killing in a serum-dependent manner. However, little is known about the contribution of sialylation to complement-independent, direct Gc-neutrophil interactions. In the absence of complement, we found sialylated Gc expressing opacity-associated (Opa) proteins decreased the oxidative burst and granule exocytosis from primary human neutrophils. In addition, sialylated Opa+ Gc survived better than vehicle treated or Δlst Gc when challenged with neutrophils. However, Gc sialylation did not significantly affect Opa-dependent association with or internalization of Gc by neutrophils. Previous studies have implicated sialic acid-binding immunoglobulin-type lectins (Siglecs) in modulating neutrophil interactions with sialylated Gc. Blocking neutrophil Siglecs with antibodies that bind to their extracellular domains eliminated the ability of sialylated Opa+ Gc to suppress the oxidative burst and resist neutrophil killing. These findings highlight a new role for sialylation in Gc evasion of human innate immunity, with implications for the development of vaccines and therapeutics for gonorrhea. IMPORTANCE Neisseria gonorrhoeae, the bacterium that causes gonorrhea, is an urgent global health concern due to increasing infection rates, widespread antibiotic resistance, and its ability to thwart protective immune responses. The mechanisms by which Gc subverts protective immune responses remain poorly characterized. One way N. gonorrhoeae evades human immunity is by adding sialic acid that is scavenged from the host onto its lipooligosaccharide, using the sialyltransferase Lst. Here, we found that sialylation enhances N. gonorrhoeae survival from neutrophil assault and inhibits neutrophil activation, independently of the complement system. Our results implicate bacterial binding of sialic acid-binding lectins (Siglecs) on the neutrophil surface, which dampens neutrophil antimicrobial responses. This work identifies a new role for sialylation in protecting N. gonorrhoeae from cellular innate immunity, which can be targeted to enhance the human immune response in gonorrhea.
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Affiliation(s)
- Amaris J. Cardenas
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Keena S. Thomas
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Mary W. Broden
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Noel J. Ferraro
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA
| | - Marcos M. Pires
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, USA
| | - Constance M. John
- VA Medical Center and University of California, San Francisco, San Francisco, California, USA
| | - Gary A. Jarvis
- VA Medical Center and University of California, San Francisco, San Francisco, California, USA
| | - Alison K. Criss
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
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2
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Geslewitz WE, Cardenas A, Zhou X, Zhang Y, Criss AK, Seifert HS. Development and implementation of a Type I-C CRISPR-based programmable repression system for Neisseria gonorrhoeae. mBio 2024; 15:e0302523. [PMID: 38126782 PMCID: PMC10865793 DOI: 10.1128/mbio.03025-23] [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: 11/10/2023] [Accepted: 11/15/2023] [Indexed: 12/23/2023] Open
Abstract
Clustered regularly interspaced short palindromic repeats (CRISPR) are prokaryotic adaptive immune systems regularly utilized as DNA-editing tools. While Neisseria gonorrhoeae does not have an endogenous CRISPR, the commensal species Neisseria lactamica encodes a functional Type I-C CRISPR-Cas system. We have established an isopropyl β-d-1-thiogalactopyranoside added (IPTG)-inducible, CRISPR interference (CRISPRi) platform based on the N. lactamica Type I-C CRISPR missing the Cas3 nuclease to allow locus-specific transcriptional repression. As proof of principle, we targeted a non-phase-variable version of the opaD gene. We show that CRISPRi can downregulate opaD gene and protein expression, resulting in bacterial inability to stimulate neutrophil oxidative responses and to bind to an N-terminal fragment of CEACAM1. Importantly, we used CRISPRi to effectively knockdown all the transcripts of all 11 opa genes using a five-spacer CRISPR array, allowing control of the entire phase-variable opa family in strain FA1090. We also report that repression is reversible following IPTG removal. Finally, we showed that the Type I-C CRISPRi system can conditionally reduce the expression of two essential genes. This CRISPRi system will allow the interrogation of every Gc gene, essential and non-essential, to study physiology and pathogenesis and aid in antimicrobial development.IMPORTANCEClustered regularly interspaced short palindromic repeats (CRISPR)-Cas systems have proven instrumental in genetically manipulating many eukaryotic and prokaryotic organisms. Despite its usefulness, a CRISPR system had yet to be developed for use in Neisseria gonorrhoeae (Gc), a bacterium that is the main etiological agent of gonorrhea infection. Here, we developed a programmable and IPTG-inducible Type I-C CRISPR interference (CRISPRi) system derived from the commensal species Neisseria lactamica as a gene repression system in Gc. As opposed to generating genetic knockouts, the Type I-C CRISPRi system allows us to block transcription of specific genes without generating deletions in the DNA. We explored the properties of this system and found that a minimal spacer array is sufficient for gene repression while also facilitating efficient spacer reprogramming. Importantly, we also show that we can use CRISPRi to knockdown genes that are essential to Gc that cannot normally be knocked out under laboratory settings. Gc encodes ~800 essential genes, many of which have no predicted function. We predict that this Type I-C CRISPRi system can be used to help categorize gene functions and perhaps contribute to the development of novel therapeutics for gonorrhea.
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Affiliation(s)
- Wendy E. Geslewitz
- Department of Microbiology and Immunology, Northwestern University, Chicago, Illinois, USA
| | - Amaris Cardenas
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Xufei Zhou
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Yan Zhang
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan, USA
| | - Alison K. Criss
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
| | - H Steven Seifert
- Department of Microbiology and Immunology, Northwestern University, Chicago, Illinois, USA
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3
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Cardenas AJ, Thomas KS, Broden MW, Ferraro NJ, John CM, Pires MM, Jarvis GA, Criss AK. Neisseria gonorrhoeae scavenges host sialic acid for Siglec-mediated, complement-independent suppression of neutrophil activation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.17.576097. [PMID: 38293026 PMCID: PMC10827150 DOI: 10.1101/2024.01.17.576097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
Gonorrhea, caused by the bacterium Neisseria gonorrhoeae (Gc), is characterized by neutrophil influx to infection sites. Gc has developed mechanisms to resist killing by neutrophils that include modifications to its surface lipooligosaccharide (LOS). One such LOS modification is sialylation: Gc sialylates its terminal LOS sugars with cytidine-5'-monophosphate-N-acetylneuraminic acid (CMP-NANA) scavenged from the host using LOS sialyltransferase (Lst), since Gc cannot make its own sialic acid. Sialylation enables sensitive strains of Gc to resist complement-mediated killing in a serum-dependent manner. However, little is known about the contribution of sialylation to complement-independent, direct Gc-neutrophil interactions. In the absence of complement, we found sialylated Gc expressing opacity-associated (Opa) proteins decreased the oxidative burst and granule exocytosis from primary human neutrophils. In addition, sialylated Opa+ Gc survived better than vehicle treated or Δlst Gc when challenged with neutrophils. However, Gc sialylation did not significantly affect Opa-dependent association with or internalization of Gc by neutrophils. Previous studies have implicated sialic acid-binding immunoglobulin-type lectins (Siglecs) in modulating neutrophil interactions with sialylated Gc. Blocking neutrophil Siglecs with antibodies that bind to their extracellular domains eliminated the ability of sialylated Opa+ Gc to suppress oxidative burst and resist neutrophil killing. These findings highlight a new role for sialylation in Gc evasion of human innate immunity, with implications for the development of vaccines and therapeutics for gonorrhea.
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Affiliation(s)
- Amaris J Cardenas
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Keena S. Thomas
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Mary W. Broden
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Noel J. Ferraro
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Constance M. John
- VA Medical Center and University of California, San Francisco, San Francisco, CA, USA
| | - Marcos M. Pires
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | - Gary A. Jarvis
- VA Medical Center and University of California, San Francisco, San Francisco, CA, USA
| | - Alison K. Criss
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA
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4
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Smirnov A, Daily KP, Gray MC, Ragland SA, Werner LM, Brittany Johnson M, Eby JC, Hewlett EL, Taylor RP, Criss AK. Phagocytosis via complement receptor 3 enables microbes to evade killing by neutrophils. J Leukoc Biol 2023; 114:1-20. [PMID: 36882066 PMCID: PMC10949953 DOI: 10.1093/jleuko/qiad028] [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: 11/17/2022] [Revised: 02/19/2023] [Accepted: 02/23/2023] [Indexed: 03/09/2023] Open
Abstract
CR3 (CD11b/CD18; αmβ2 integrin) is a conserved phagocytic receptor. The active conformation of CR3 binds the iC3b fragment of complement C3 as well as many host and microbial ligands, leading to actin-dependent phagocytosis. There are conflicting reports about how CR3 engagement affects the fate of phagocytosed substrates. Using imaging flow cytometry, we confirmed that binding and internalization of iC3b-opsonized polystyrene beads by primary human neutrophils was CR3-dependent. iC3b-opsonized beads did not stimulate neutrophil reactive oxygen species, and most beads were found in primary granule-negative phagosomes. Similarly, Neisseria gonorrhoeae that does not express phase-variable Opa proteins suppresses neutrophil reactive oxygen species and delays phagolysosome formation. Here, binding and internalization of Opa-deleted (Δopa) N. gonorrhoeae by adherent human neutrophils was inhibited using blocking antibodies against CR3 and by adding neutrophil inhibitory factor, which targets the CD11b I-domain. No detectable C3 was deposited on N. gonorrhoeae in the presence of neutrophils alone. Conversely, overexpressing CD11b in HL-60 promyelocytes enhanced Δopa N. gonorrhoeae phagocytosis, which required the CD11b I-domain. Phagocytosis of N. gonorrhoeae was also inhibited in mouse neutrophils that were CD11b-deficient or treated with anti-CD11b. Phorbol ester treatment upregulated surface CR3 on neutrophils in suspension, enabling CR3-dependent phagocytosis of Δopa N. gonorrhoeae. Neutrophils exposed to Δopa N. gonorrhoeae had limited phosphorylation of Erk1/2, p38, and JNK. Neutrophil phagocytosis of unopsonized Mycobacterium smegmatis, which also resides in immature phagosomes, was CR3-dependent and did not elicit reactive oxygen species. We suggest that CR3-mediated phagocytosis is a silent mode of entry into neutrophils, which is appropriated by diverse pathogens to subvert phagocytic killing.
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Affiliation(s)
- Asya Smirnov
- Department of Microbiology, Immunology, and Cancer Biology
| | | | - Mary C. Gray
- Department of Microbiology, Immunology, and Cancer Biology
| | | | | | | | - Joshua C. Eby
- Division of Infectious Diseases and International Health, Department of Medicine
| | - Erik L. Hewlett
- Division of Infectious Diseases and International Health, Department of Medicine
| | - Ronald P. Taylor
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine
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5
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Goob G, Adrian J, Cossu C, Hauck CR. Phagocytosis mediated by the human granulocyte receptor CEACAM3 is limited by the receptor-type protein tyrosine phosphatase PTPRJ. J Biol Chem 2022; 298:102269. [PMID: 35850306 PMCID: PMC9418913 DOI: 10.1016/j.jbc.2022.102269] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 07/04/2022] [Accepted: 07/06/2022] [Indexed: 11/18/2022] Open
Abstract
Carcinoembryonic Antigen-related Cell Adhesion Molecule 3 (CEACAM3) is a human granulocyte receptor mediating the efficient phagocytosis of a subset of human-restricted bacterial pathogens. Its function depends on phosphorylation of a tyrosine-based sequence motif, but the enzyme(s) responsible for reversing this modification are unclear. Here, we identify the receptor-type protein tyrosine phosphatase PTPRJ as a negative regulator of CEACAM3-mediated phagocytosis. We show depletion of PTPRJ results in a gain-of-function phenotype, while overexpression of a constitutively active PTPRJ phosphatase strongly reduces bacterial uptake via CEACAM3. We also determined that recombinant PTPRJ directly dephosphorylates the cytoplasmic tyrosine residues of purified full-length CEACAM3 and recognizes synthetic CEACAM3-derived phospho-peptides as substrates. Dephosphorylation of CEACAM3 by PTPRJ is also observed in intact cells, thereby limiting receptor-initiated cytoskeletal re-arrangements, lamellipodia formation, and bacterial uptake. Finally, we show that human phagocytes deficient for PTPRJ exhibit exaggerated lamellipodia formation and enhanced opsonin-independent phagocytosis of CEACAM3-binding bacteria. Taken together, our results highlight PTPRJ as a bona fide negative regulator of CEACAM3-initiated phagocyte functions, revealing a potential molecular target to limit CEACAM3-driven inflammatory responses.
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Affiliation(s)
- Griseldis Goob
- Lehrstuhl Zellbiologie, Fachbereich Biologie, Universität Konstanz, Germany
| | - Jonas Adrian
- Lehrstuhl Zellbiologie, Fachbereich Biologie, Universität Konstanz, Germany
| | - Chiara Cossu
- Lehrstuhl Zellbiologie, Fachbereich Biologie, Universität Konstanz, Germany
| | - Christof R Hauck
- Lehrstuhl Zellbiologie, Fachbereich Biologie, Universität Konstanz, Germany; Konstanz Research School Chemical Biology, Universität Konstanz, Germany.
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6
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Abstract
Neisseria gonorrhoeae is an obligate human pathogen that is the cause of the sexually transmitted disease gonorrhoea. Recently, there has been a surge in gonorrhoea cases that has been exacerbated by the rapid rise in gonococcal multidrug resistance to all useful antimicrobials resulting in this organism becoming a significant public health burden. Therefore, there is a clear and present need to understand the organism's biology through its physiology and pathogenesis to help develop new intervention strategies. The gonococcus initially colonises and adheres to host mucosal surfaces utilising a type IV pilus that helps with microcolony formation. Other adhesion strategies include the porin, PorB, and the phase variable outer membrane protein Opa. The gonococcus is able to subvert complement mediated killing and opsonisation by sialylation of its lipooligosaccharide and deploys a series of anti-phagocytic mechanisms. N. gonorrhoeae is a fastidious organism that is able to grow on a limited number of primary carbon sources such as glucose and lactate. The utilization of lactate by the gonococcus has been implicated in a number of pathogenicity mechanisms. The bacterium lives mainly in microaerobic environments and can grow both aerobically and anaerobically with the aid of nitrite. The gonococcus does not produce siderophores for scavenging iron but can utilize some produced by other bacteria, and it is able to successful chelate iron from host haem, transferrin and lactoferrin. The gonococcus is an incredibly versatile human pathogen; in the following chapter, we detail the intricate mechanisms used by the bacterium to invade and survive within the host.
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Affiliation(s)
- Luke R Green
- Department of Infection, Immunity & Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Joby Cole
- Department of Infection, Immunity & Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Ernesto Feliz Diaz Parga
- Department of Infection, Immunity & Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Jonathan G Shaw
- Department of Infection, Immunity & Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom.
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Barnier JP, Meyer J, Kolappan S, Bouzinba-Ségard H, Gesbert G, Jamet A, Frapy E, Schönherr-Hellec S, Capel E, Virion Z, Dupuis M, Bille E, Morand P, Schmitt T, Bourdoulous S, Nassif X, Craig L, Coureuil M. The minor pilin PilV provides a conserved adhesion site throughout the antigenically variable meningococcal type IV pilus. Proc Natl Acad Sci U S A 2021; 118:e2109364118. [PMID: 34725157 PMCID: PMC8609321 DOI: 10.1073/pnas.2109364118] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 09/16/2021] [Indexed: 01/14/2023] Open
Abstract
Neisseria meningitidis utilizes type IV pili (T4P) to adhere to and colonize host endothelial cells, a process at the heart of meningococcal invasive diseases leading to meningitis and sepsis. T4P are polymers of an antigenically variable major pilin building block, PilE, plus several core minor pilins that initiate pilus assembly and are thought to be located at the pilus tip. Adhesion of N. meningitidis to human endothelial cells requires both PilE and a conserved noncore minor pilin PilV, but the localization of PilV and its precise role in this process remains to be clarified. Here, we show that both PilE and PilV promote adhesion to endothelial vessels in vivo. The substantial adhesion defect observed for pilV mutants suggests it is the main adhesin. Consistent with this observation, superresolution microscopy showed the abundant distribution of PilV throughout the pilus. We determined the crystal structure of PilV and modeled it within the pilus filament. The small size of PilV causes it to be recessed relative to adjacent PilE subunits, which are dominated by a prominent hypervariable loop. Nonetheless, we identified a conserved surface-exposed adhesive loop on PilV by alanine scanning mutagenesis. Critically, antibodies directed against PilV inhibit N. meningitidis colonization of human skin grafts. These findings explain how N. meningitidis T4P undergo antigenic variation to evade the humoral immune response while maintaining their adhesive function and establish the potential of this highly conserved minor pilin as a vaccine and therapeutic target for the prevention and treatment of N. meningitidis infections.
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Affiliation(s)
- Jean-Philippe Barnier
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
- Service de Microbiologie, Assistance Publique-Hôpitaux de Paris, Centre-Université de Paris, Hôpital Necker Enfants-Malades, Paris 75015, France
| | - Julie Meyer
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
| | - Subramania Kolappan
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC V5A 3Y6, Canada
| | - Haniaa Bouzinba-Ségard
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1016, CNRS UMR 8104, Institut Cochin, Paris 75014, France
| | - Gaël Gesbert
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
| | - Anne Jamet
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
- Service de Microbiologie, Assistance Publique-Hôpitaux de Paris, Centre-Université de Paris, Hôpital Necker Enfants-Malades, Paris 75015, France
| | - Eric Frapy
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
| | - Sophia Schönherr-Hellec
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
| | - Elena Capel
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
| | - Zoé Virion
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
| | - Marion Dupuis
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
| | - Emmanuelle Bille
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
- Service de Microbiologie, Assistance Publique-Hôpitaux de Paris, Centre-Université de Paris, Hôpital Necker Enfants-Malades, Paris 75015, France
| | - Philippe Morand
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
- Service de Bactériologie, Assistance Publique-Hôpitaux de Paris, Centre-Université de Paris, Hôpital Cochin, Paris 75014, France
| | - Taliah Schmitt
- Service de Chirurgie Reconstructrice et Plastique, Groupe Hospitalier Paris Saint-Joseph, Paris 75014, France
| | - Sandrine Bourdoulous
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1016, CNRS UMR 8104, Institut Cochin, Paris 75014, France
| | - Xavier Nassif
- Faculté de Médecine, Université de Paris, Paris 75006, France
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
- Service de Microbiologie, Assistance Publique-Hôpitaux de Paris, Centre-Université de Paris, Hôpital Necker Enfants-Malades, Paris 75015, France
| | - Lisa Craig
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC V5A 3Y6, Canada;
| | - Mathieu Coureuil
- Faculté de Médecine, Université de Paris, Paris 75006, France;
- INSERM U1151, CNRS UMR 8253, Institut Necker Enfants-Malades, Paris 75015, France
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8
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Heydarian M, Yang T, Schweinlin M, Steinke M, Walles H, Rudel T, Kozjak-Pavlovic V. Biomimetic Human Tissue Model for Long-Term Study of Neisseria gonorrhoeae Infection. Front Microbiol 2019; 10:1740. [PMID: 31417529 PMCID: PMC6685398 DOI: 10.3389/fmicb.2019.01740] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 07/15/2019] [Indexed: 11/18/2022] Open
Abstract
Gonorrhea is the second most common sexually transmitted infection in the world and is caused by Gram-negative diplococcus Neisseria gonorrhoeae. Since N. gonorrhoeae is a human-specific pathogen, animal infection models are only of limited use. Therefore, a suitable in vitro cell culture model for studying the complete infection including adhesion, transmigration and transport to deeper tissue layers is required. In the present study, we generated three independent 3D tissue models based on porcine small intestinal submucosa (SIS) scaffold by co-culturing human dermal fibroblasts with human colorectal carcinoma, endometrial epithelial, and male uroepithelial cells. Functional analyses such as transepithelial electrical resistance (TEER) and FITC-dextran assay indicated the high barrier integrity of the created monolayer. The histological, immunohistochemical, and ultra-structural analyses showed that the 3D SIS scaffold-based models closely mimic the main characteristics of the site of gonococcal infection in human host including the epithelial monolayer, the underlying connective tissue, mucus production, tight junction, and microvilli formation. We infected the established 3D tissue models with different N. gonorrhoeae strains and derivatives presenting various phenotypes regarding adhesion and invasion. The results indicated that the disruption of tight junctions and increase in interleukin production in response to the infection is strain and cell type-dependent. In addition, the models supported bacterial survival and proved to be better suitable for studying infection over the course of several days in comparison to commonly used Transwell® models. This was primarily due to increased resilience of the SIS scaffold models to infection in terms of changes in permeability, cell destruction and bacterial transmigration. In summary, the SIS scaffold-based 3D tissue models of human mucosal tissues represent promising tools for investigating N. gonorrhoeae infections under close-to-natural conditions.
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Affiliation(s)
| | - Tao Yang
- Biocenter, Chair of Microbiology, University of Würzburg, Würzburg, Germany
| | - Matthias Schweinlin
- Chair of Tissue Engineering and Regenerative Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Maria Steinke
- Chair of Tissue Engineering and Regenerative Medicine, University Hospital Würzburg, Würzburg, Germany
| | - Heike Walles
- Research Center "Dynamic Systems: Systems Engineering" (CDS), Otto von-Guericke-University, Magdeburg, Germany
| | - Thomas Rudel
- Biocenter, Chair of Microbiology, University of Würzburg, Würzburg, Germany
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9
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Denis K, Le Bris M, Le Guennec L, Barnier JP, Faure C, Gouge A, Bouzinba-Ségard H, Jamet A, Euphrasie D, Durel B, Barois N, Pelissier P, Morand PC, Coureuil M, Lafont F, Join-Lambert O, Nassif X, Bourdoulous S. Targeting Type IV pili as an antivirulence strategy against invasive meningococcal disease. Nat Microbiol 2019; 4:972-984. [PMID: 30911127 DOI: 10.1038/s41564-019-0395-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 01/30/2019] [Indexed: 11/09/2022]
Abstract
Bacterial virulence factors are attractive targets for the development of therapeutics. Type IV pili, which are associated with a remarkable array of properties including motility, the interaction between bacteria and attachment to biotic and abiotic surfaces, represent particularly appealing virulence factor targets. Type IV pili are present in numerous bacterial species and are critical for their pathogenesis. In this study, we report that trifluoperazine and related phenothiazines block functions associated with Type IV pili in different bacterial pathogens, by affecting piliation within minutes. Using Neisseria meningitidis as a paradigm of Gram-negative bacterial pathogens that require Type IV pili for pathogenesis, we show that piliation is sensitive to altered activity of the Na+ pumping NADH-ubiquinone oxidoreductase (Na+-NQR) complex and that these compounds probably altered the establishment of the sodium gradient. In vivo, these compounds exert a strong protective effect. They reduce meningococcal colonization of the human vessels and prevent subsequent vascular dysfunctions, intravascular coagulation and overwhelming inflammation, the hallmarks of invasive meningococcal infections. Finally, they reduce lethality. This work provides a proof of concept that compounds with activity against bacterial Type IV pili could beneficially participate in the treatment of infections caused by Type IV pilus-expressing bacteria.
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Affiliation(s)
- Kevin Denis
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Marion Le Bris
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Loic Le Guennec
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Jean-Philippe Barnier
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Hôpital Necker Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Camille Faure
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Anne Gouge
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Haniaa Bouzinba-Ségard
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Anne Jamet
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Hôpital Necker Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Daniel Euphrasie
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Hôpital Necker Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Beatrice Durel
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Nicolas Barois
- Cellular Microbiology and Physics of Infection Group, Centre for Infection and Immunity of Lille, Institut Pasteur de Lille, Lille, France.,UMR 8204, CNRS, Lille, France.,U1019, Inserm, Lille, France.,Université de Lille, Lille, France
| | - Philippe Pelissier
- Service de Chirurgie Reconstructrice et Plastique, Fondation Hôpital Saint Joseph, Paris, France
| | - Philippe C Morand
- U1016, Institut Cochin, Inserm, Paris, France.,UMR8104, CNRS, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Mathieu Coureuil
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Frank Lafont
- Cellular Microbiology and Physics of Infection Group, Centre for Infection and Immunity of Lille, Institut Pasteur de Lille, Lille, France.,UMR 8204, CNRS, Lille, France.,U1019, Inserm, Lille, France.,Université de Lille, Lille, France
| | - Olivier Join-Lambert
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Hôpital Necker Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Xavier Nassif
- U1151, Institut Necker Enfants Malades, Inserm, Paris, France.,UMR 8253, CNRS, Paris, France.,Faculté de Médecine, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Hôpital Necker Enfants Malades, Assistance Publique - Hôpitaux de Paris, Paris, France
| | - Sandrine Bourdoulous
- U1016, Institut Cochin, Inserm, Paris, France. .,UMR8104, CNRS, Paris, France. .,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
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10
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A homopolymeric adenosine tract in the promoter region of nspA influences factor H-mediated serum resistance in Neisseria meningitidis. Sci Rep 2019; 9:2736. [PMID: 30804422 PMCID: PMC6389960 DOI: 10.1038/s41598-019-39231-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 01/18/2019] [Indexed: 01/18/2023] Open
Abstract
Although usually asymptomatically colonizing the human nasopharynx, the Gram-negative bacterium Neisseria meningitidis (meningococcus) can spread to the blood stream and cause invasive disease. For survival in blood, N. meningitidis evades the complement system by expression of a polysaccharide capsule and surface proteins sequestering the complement regulator factor H (fH). Meningococcal strains belonging to the sequence type (ST-) 41/44 clonal complex (cc41/44) cause a major proportion of serogroup B meningococcal disease worldwide, but they are also common in asymptomatic carriers. Proteome analysis comparing cc41/44 isolates from invasive disease versus carriage revealed differential expression levels of the outer membrane protein NspA, which binds fH. Deletion of nspA reduced serum resistance and NspA expression correlated with fH sequestration. Expression levels of NspA depended on the length of a homopolymeric tract in the nspA promoter: A 5-adenosine tract dictated low NspA expression, whereas a 6-adenosine motif guided high NspA expression. Screening German cc41/44 strain collections revealed the 6-adenosine motif in 39% of disease isolates, but only in 3.4% of carriage isolates. Thus, high NspA expression is associated with disease, but not strictly required. The 6-adenosine nspA promoter is most common to the cc41/44, but is also found in other hypervirulent clonal complexes.
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11
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Adrian J, Bonsignore P, Hammer S, Frickey T, Hauck CR. Adaptation to Host-Specific Bacterial Pathogens Drives Rapid Evolution of a Human Innate Immune Receptor. Curr Biol 2019; 29:616-630.e5. [PMID: 30744974 DOI: 10.1016/j.cub.2019.01.058] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/12/2018] [Accepted: 01/22/2019] [Indexed: 12/25/2022]
Abstract
The selective pressure by infectious agents is a major driving force in the evolution of humans and other mammals. Members of the carcinoembryonic antigen-related cell adhesion molecule (CEACAM) family serve as receptors for bacterial pathogens of the genera Haemophilus, Helicobacter, Neisseria, and Moraxella, which engage CEACAMs via distinct surface adhesins. While microbial attachment to epithelial CEACAMs facilitates host colonization, recognition by CEACAM3, a phagocytic receptor expressed by granulocytes, eliminates CEACAM-binding bacteria. Sequence analysis of primate CEACAM3 orthologs reveals that this innate immune receptor is one of the most rapidly evolving human proteins. In particular, the pathogen-binding extracellular domain of CEACAM3 shows a high degree of non-synonymous versus synonymous nucleotide exchanges, indicating an exceptionally strong positive selection. Using CEACAM3 domains derived from different primates, we find that the amino acid alterations found in CEACAM3 translate into characteristic binding patterns for bacterial adhesins. One such amino acid residue is F62 in human and chimp CEACAM3, which is not present in other primates and which is critical for binding the OMP P1 adhesin of Haemophilus aegyptius. Incorporation of the F62-containing motif into gorilla CEACAM3 results in a gain-of-function phenotype with regard to phagocytosis of H. aegyptius. Moreover, CEACAM3 polymorphisms found in human subpopulations widen the spectrum of recognized bacterial adhesins, suggesting an ongoing multivariate selection acting on this innate immune receptor. The species-specific detection of diverse bacterial adhesins helps to explain the exceptionally fast evolution of CEACAM3 within the primate lineage and provides an example of Red Queen dynamics in the human genome.
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Affiliation(s)
- Jonas Adrian
- Lehrstuhl für Zellbiologie, Fachbereich Biologie, Universität Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Patrizia Bonsignore
- Lehrstuhl für Zellbiologie, Fachbereich Biologie, Universität Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Sebastian Hammer
- Lehrstuhl für Zellbiologie, Fachbereich Biologie, Universität Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Tancred Frickey
- Forest Industry Informatics, Scion, Te Papa Tipu Innovation Park, 49 Sala Street, 3015 Rotorua, New Zealand; Konstanz Research School-Chemical Biology, Universität Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Christof R Hauck
- Lehrstuhl für Zellbiologie, Fachbereich Biologie, Universität Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany; Konstanz Research School-Chemical Biology, Universität Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany.
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12
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Strobel L, Johswich KO. Anticoagulants impact on innate immune responses and bacterial survival in whole blood models of Neisseria meningitidis infection. Sci Rep 2018; 8:10225. [PMID: 29977064 PMCID: PMC6033889 DOI: 10.1038/s41598-018-28583-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 06/26/2018] [Indexed: 12/13/2022] Open
Abstract
Neisseria meningitidis (meningococcus) causes invasive diseases such as meningitis or septicaemia. Ex vivo infection of human whole blood is a valuable tool to study meningococcal virulence factors and the host innate immune responses. In order to consider effects of cellular mediators, the coagulation cascade must be inhibited to avoid clotting. There is considerable variation in the anticoagulants used among studies of N. meningitidis whole blood infections, featuring citrate, heparin or derivatives of hirudin, a polypeptide from leech saliva. Here, we compare the influence of these three different anticoagulants, and additionally Mg/EGTA, on host innate immune responses as well as on viability of N. meningitidis strains isolated from healthy carriers and disease cases, reflecting different sequence types and capsule phenotypes. We found that the anticoagulants significantly impact on cellular responses and, strain-dependently, also on bacterial survival. Hirudin does not inhibit complement and is therefore superior over the other anticoagulants; indeed hirudin-plasma most closely reflects the characteristics of serum during N. meningitidis infection. We further demonstrate the impact of heparin on complement activation on N. meningitidis and its consequences on meningococcal survival in immune sera, which appears to be independent of the heparin binding antigens Opc and NHBA.
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Affiliation(s)
- Lea Strobel
- Institute for Hygiene and Microbiology, University of Wuerzburg, Wuerzburg, Germany
| | - Kay O Johswich
- Institute for Hygiene and Microbiology, University of Wuerzburg, Wuerzburg, Germany.
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13
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Bille E, Meyer J, Jamet A, Euphrasie D, Barnier JP, Brissac T, Larsen A, Pelissier P, Nassif X. A virulence-associated filamentous bacteriophage of Neisseria meningitidis increases host-cell colonisation. PLoS Pathog 2017; 13:e1006495. [PMID: 28704569 PMCID: PMC5526601 DOI: 10.1371/journal.ppat.1006495] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 07/25/2017] [Accepted: 06/27/2017] [Indexed: 01/31/2023] Open
Abstract
Neisseria meningitidis is a commensal of human nasopharynx. In some circumstances, this bacteria can invade the bloodstream and, after crossing the blood brain barrier, the meninges. A filamentous phage, designated MDAΦ for Meningococcal Disease Associated, has been associated with invasive disease. In this work we show that the prophage is not associated with a higher virulence during the bloodstream phase of the disease. However, looking at the interaction of N. meningitidis with epithelial cells, a step essential for colonization of the nasopharynx, we demonstrate that the presence of the prophage, via the production of viruses, increases colonization of encapsulated meningococci onto monolayers of epithelial cells. The analysis of the biomass covering the epithelial cells revealed that meningococci are bound to the apical surface of host cells by few layers of heavily piliated bacteria, whereas, in the upper layers, bacteria are non-piliated but surrounded by phage particles which (i) form bundles of filaments, and/or (ii) are in some places associated with bacteria. The latter are likely to correspond to growing bacteriophages during their extrusion through the outer membrane. These data suggest that, as the biomass increases, the loss of piliation in the upper layers of the biomass does not allow type IV pilus bacterial aggregation, but is compensated by a large production of phage particles that promote bacterial aggregation via the formation of bundles of phage filaments linked to the bacterial cell walls. We propose that MDAΦ by increasing bacterial colonization in the mucosa at the site-of-entry, increase the occurrence of diseases. Bacteriophages are bacterial viruses, which in some cases encode for virulence factors and increase bacterial virulence. Comparative genomic of several strains of Neisseria meningitidis, a major human pathogen, identified the presence of an 8kb prophage in strains belonging to invasive clonal complexes. The analysis of this filamentous bacteriophage, designated MDA for Meningococcal Disease Associated (MDAΦ) did not reveal any obvious virulence factors responsible for an increase invasiveness of strains carrying this prophage. Using our animal model mimicking the septicemic phase of the neisserial invasive diseases, we demonstrate that the presence of the MDAΦ is not associated with a higher virulence, but we show that the bacteriophage particles, by promoting bacteria-bacteria interactions, increase the biomass of bacteria colonizing a monolayer of epithelial cells. These data suggest that the increased invasiveness mediated by the MDAΦ bacteriophage is likely to be due to a better ability of the bacteria to colonize the nasopharyngeal mucosa.
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Affiliation(s)
- Emmanuelle Bille
- Institut Necker-Enfants Malades, INSERM U1151, CNRS UMR 8253, Paris, France
- Université Paris Descartes, Paris, France
- Service de Microbiologie, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France
- * E-mail:
| | - Julie Meyer
- Institut Necker-Enfants Malades, INSERM U1151, CNRS UMR 8253, Paris, France
- Université Paris Descartes, Paris, France
| | - Anne Jamet
- Institut Necker-Enfants Malades, INSERM U1151, CNRS UMR 8253, Paris, France
- Université Paris Descartes, Paris, France
- Service de Microbiologie, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Daniel Euphrasie
- Institut Necker-Enfants Malades, INSERM U1151, CNRS UMR 8253, Paris, France
- Université Paris Descartes, Paris, France
| | - Jean-Philippe Barnier
- Institut Necker-Enfants Malades, INSERM U1151, CNRS UMR 8253, Paris, France
- Université Paris Descartes, Paris, France
- Service de Microbiologie, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Terry Brissac
- Institut Necker-Enfants Malades, INSERM U1151, CNRS UMR 8253, Paris, France
- Université Paris Descartes, Paris, France
| | - Anna Larsen
- Institut Necker-Enfants Malades, INSERM U1151, CNRS UMR 8253, Paris, France
- Université Paris Descartes, Paris, France
| | - Philippe Pelissier
- Service de Chirurgie Reconstructrice et Plastique, Fondation Hôpital Saint Joseph, Paris, France
| | - Xavier Nassif
- Institut Necker-Enfants Malades, INSERM U1151, CNRS UMR 8253, Paris, France
- Université Paris Descartes, Paris, France
- Service de Microbiologie, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France
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14
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Klughammer J, Dittrich M, Blom J, Mitesser V, Vogel U, Frosch M, Goesmann A, Müller T, Schoen C. Comparative Genome Sequencing Reveals Within-Host Genetic Changes in Neisseria meningitidis during Invasive Disease. PLoS One 2017; 12:e0169892. [PMID: 28081260 PMCID: PMC5231331 DOI: 10.1371/journal.pone.0169892] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 12/22/2016] [Indexed: 11/29/2022] Open
Abstract
Some members of the physiological human microbiome occasionally cause life-threatening disease even in immunocompetent individuals. A prime example of such a commensal pathogen is Neisseria meningitidis, which normally resides in the human nasopharynx but is also a leading cause of sepsis and epidemic meningitis. Using N. meningitidis as model organism, we tested the hypothesis that virulence of commensal pathogens is a consequence of within host evolution and selection of invasive variants due to mutations at contingency genes, a mechanism called phase variation. In line with the hypothesis that phase variation evolved as an adaptation to colonize diverse hosts, computational comparisons of all 27 to date completely sequenced and annotated meningococcal genomes retrieved from public databases showed that contingency genes are indeed enriched for genes involved in host interactions. To assess within-host genetic changes in meningococci, we further used ultra-deep whole-genome sequencing of throat-blood strain pairs isolated from four patients suffering from invasive meningococcal disease. We detected up to three mutations per strain pair, affecting predominantly contingency genes involved in type IV pilus biogenesis. However, there was not a single (set) of mutation(s) that could invariably be found in all four pairs of strains. Phenotypic assays further showed that these genetic changes were generally not associated with increased serum resistance, higher fitness in human blood ex vivo or differences in the interaction with human epithelial and endothelial cells in vitro. In conclusion, we hypothesize that virulence of meningococci results from accidental emergence of invasive variants during carriage and without within host evolution of invasive phenotypes during disease progression in vivo.
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Affiliation(s)
- Johanna Klughammer
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Marcus Dittrich
- Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
- Institute of Human Genetics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Jochen Blom
- Institute for Bioinformatics and Systems Biology, Justus Liebig University Giessen, Giessen, Germany
| | - Vera Mitesser
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Ulrich Vogel
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
- Research Center for Infectious Diseases, University of Würzburg, Würzburg, Germany
- German Reference Laboratory for Meningococci and Haemophilus influenzae, Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Matthias Frosch
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
- Research Center for Infectious Diseases, University of Würzburg, Würzburg, Germany
- German Reference Laboratory for Meningococci and Haemophilus influenzae, Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Alexander Goesmann
- Institute for Bioinformatics and Systems Biology, Justus Liebig University Giessen, Giessen, Germany
| | - Tobias Müller
- Department of Bioinformatics, Biocenter, University of Würzburg, Würzburg, Germany
| | - Christoph Schoen
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
- Research Center for Infectious Diseases, University of Würzburg, Würzburg, Germany
- * E-mail:
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15
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Meyer J, Brissac T, Frapy E, Omer H, Euphrasie D, Bonavita A, Nassif X, Bille E. Characterization of MDAΦ, a temperate filamentous bacteriophage of Neisseria meningitidis. MICROBIOLOGY-SGM 2015; 162:268-282. [PMID: 26602366 DOI: 10.1099/mic.0.000215] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The mechanism by which Neisseria meningitidis becomes invasive is not well understood. Comparative genomics identified the presence of an 8 kb island in strains belonging to invasive clonal complexes. This island was designated MDA for meningococcal disease associated. MDA is highly conserved among meningococcal isolates and its analysis revealed a genomic organization similar to that of a filamentous prophage such as CTXΦ of Vibrio cholerae. Subsequent molecular investigations showed that the MDA island has indeed the characteristics of a filamentous prophage, which can enter into a productive cycle and is secreted using the type IV pilus (tfp) secretin PilQ. At least three genes of the prophage are necessary for the formation of the replicative cytoplasmic form (orf1, orf2 and orf9). Immunolabelling of the phage with antibodies against the major capsid protein, ORF4, confirmed that filamentous particles, about 1200 nm long, covered with ORF4 are present at the bacterial surface forming bundles in some places and interacting with pili. The MDA bacteriophage is able to infect different N. meningitidis strains, using the type IV pili as a receptor via an interaction with the adsorption protein ORF6. Altogether, these data demonstrate that the MDA island encodes a functional prophage able to produce infectious filamentous phage particles.
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Affiliation(s)
- Julie Meyer
- Institut Necker-Enfants Malades, 14 Rue Maria Helena Vieira Da Silva, CS 61431, 75014, Paris, France.,CNRS UMR 8253, Paris, France.,INSERM U1151, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Terry Brissac
- Institut Necker-Enfants Malades, 14 Rue Maria Helena Vieira Da Silva, CS 61431, 75014, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,INSERM U1151, Paris, France.,CNRS UMR 8253, Paris, France
| | - Eric Frapy
- Institut Necker-Enfants Malades, 14 Rue Maria Helena Vieira Da Silva, CS 61431, 75014, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,INSERM U1151, Paris, France.,CNRS UMR 8253, Paris, France
| | - Hélène Omer
- Institut Necker-Enfants Malades, 14 Rue Maria Helena Vieira Da Silva, CS 61431, 75014, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,INSERM U1151, Paris, France.,CNRS UMR 8253, Paris, France
| | - Daniel Euphrasie
- Institut Necker-Enfants Malades, 14 Rue Maria Helena Vieira Da Silva, CS 61431, 75014, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,INSERM U1151, Paris, France.,CNRS UMR 8253, Paris, France
| | - Adrien Bonavita
- CNRS UMR 8253, Paris, France.,Institut Necker-Enfants Malades, 14 Rue Maria Helena Vieira Da Silva, CS 61431, 75014, Paris, France.,INSERM U1151, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Xavier Nassif
- INSERM U1151, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Service de Microbiologie, Hôpital Necker-Enfants Malades, AP-HP, Paris, France.,CNRS UMR 8253, Paris, France.,Institut Necker-Enfants Malades, 14 Rue Maria Helena Vieira Da Silva, CS 61431, 75014, Paris, France
| | - Emmanuelle Bille
- Service de Microbiologie, Hôpital Necker-Enfants Malades, AP-HP, Paris, France.,CNRS UMR 8253, Paris, France.,Institut Necker-Enfants Malades, 14 Rue Maria Helena Vieira Da Silva, CS 61431, 75014, Paris, France.,INSERM U1151, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
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16
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Sterilizing immunity elicited by Neisseria meningitidis carriage shows broader protection than predicted by serum antibody cross-reactivity in CEACAM1-humanized mice. Infect Immun 2014; 83:354-63. [PMID: 25368118 DOI: 10.1128/iai.02495-14] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Neisseria meningitidis asymptomatically colonizes the human upper respiratory tract but is also the cause of meningitis and severe septicemia. Carriage or disease evokes an immune response against the infecting strain. Hitherto, we have known little about the breadth of immunity induced by natural carriage of a single strain or its implications for subsequent infectious challenge. In this study, we establish that transgenic mice expressing human CEACAM1 support nasal colonization by a variety of strains of different capsular types. Next, we nasally challenged these mice with either of the N. meningitidis strains H44/76 (serogroup B, ST-32) and 90/18311 (serogroup C, ST-11), while following the induction of strain-specific immunoglobulin. When these antisera were tested for reactivity with a diverse panel of N. meningitidis strains, very low levels of antibody were detected against all meningococcal strains, yet a mutually exclusive "fingerprint" of high-level cross-reactivity toward certain strains became apparent. To test the efficacy of these responses for protection against subsequent challenge, CEACAM1-humanized mice exposed to strain 90/18311 were then rechallenged with different N. meningitidis strains. As expected, the mice were immune to challenge with the same strain and with a closely related ST-11 strain, 38VI, while H44/76 (ST-32) could still colonize these animals. Notably, however, despite the paucity of detectable humoral response against strain 196/87 (ST-32), this strain was unable to colonize the 90/18311-exposed mice. Combined, our data suggest that current approaches may underestimate the actual breadth of mucosal protection gained through natural exposure to N. meningitidis strains.
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17
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Pathogenic Neisseria meningitidis utilizes CD147 for vascular colonization. Nat Med 2014; 20:725-31. [PMID: 24880614 PMCID: PMC7095922 DOI: 10.1038/nm.3563] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 04/10/2014] [Indexed: 01/07/2023]
Abstract
Neisseria meningitidis is a cause of meningitis epidemics worldwide and of rapidly progressing fatal septic shock. A crucial step in the pathogenesis of invasive meningococcal infections is the adhesion of bloodborne meningococci to both peripheral and brain endothelia, leading to major vascular dysfunction. Initial adhesion of pathogenic strains to endothelial cells relies on meningococcal type IV pili, but the endothelial receptor for bacterial adhesion remains unknown. Here, we report that the immunoglobulin superfamily member CD147 (also called extracellular matrix metalloproteinase inducer (EMMPRIN) or Basigin) is a critical host receptor for the meningococcal pilus components PilE and PilV. Interfering with this interaction potently inhibited the primary attachment of meningococci to human endothelial cells in vitro and prevented colonization of vessels in human brain tissue explants ex vivo and in humanized mice in vivo. These findings establish the molecular events by which meningococci target human endothelia, and they open new perspectives for treatment and prevention of meningococcus-induced vascular dysfunctions.
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18
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The hypervariable region of meningococcal major pilin PilE controls the host cell response via antigenic variation. mBio 2014; 5:e01024-13. [PMID: 24520062 PMCID: PMC3950515 DOI: 10.1128/mbio.01024-13] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Type IV pili (Tfp) are expressed by many Gram-negative bacteria to promote aggregation, adhesion, internalization, twitching motility, or natural transformation. Tfp of Neisseria meningitidis, the causative agent of cerebrospinal meningitis, are involved in the colonization of human nasopharynx. After invasion of the bloodstream, Tfp allow adhesion of N. meningitidis to human endothelial cells, which leads to the opening of the blood-brain barrier and meningitis. To achieve firm adhesion, N. meningitidis induces a host cell response that results in elongation of microvilli surrounding the meningococcal colony. Here we study the role of the major pilin subunit PilE during host cell response using human dermal microvascular endothelial cells and the pharynx carcinoma-derived FaDu epithelial cell line. We first show that some PilE variants are unable to induce a host cell response. By engineering PilE mutants, we observed that the PilE C-terminus domain, which contains a disulfide bonded region (D-region), is critical for the host cell response and that hypervariable regions confer different host cell specificities. Moreover, the study of point mutants of the pilin D-region combined with structural modeling of PilE revealed that the D-region contains two independent regions involved in signaling to human dermal microvascular endothelial cells (HDMECs) or FaDu cells. Our results indicate that the diversity of the PilE D-region sequence allows the induction of the host cell response via several receptors. This suggests that Neisseria meningitidis has evolved a powerful tool to adapt easily to many niches by modifying its ability to interact with host cells. Type IV pili (Tfp) are long appendages expressed by many Gram-negative bacteria, including Neisseria meningitidis, the causative agent of cerebrospinal meningitis. These pili are involved in many aspects of pathogenesis: natural competence, aggregation, adhesion, and twitching motility. More specifically, Neisseria meningitidis, which is devoid of a secretion system to manipulate its host, has evolved its Tfp to signal to brain endothelial cells and open the blood-brain barrier. In this report, we investigate, at the molecular level, the involvement of the major pilin subunit PilE in host cell response. Our results indicate that the PilE C-terminal domain, which contains a disulfide bonded region (D-region), is critical for the host cell response and contains two independent regions involved in host cell signaling.
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Anderson MT, Seifert HS. Phase variation leads to the misidentification of a Neisseria gonorrhoeae virulence gene. PLoS One 2013; 8:e72183. [PMID: 23977246 PMCID: PMC3745409 DOI: 10.1371/journal.pone.0072183] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 07/05/2013] [Indexed: 11/18/2022] Open
Abstract
Neisseria gonorrhoeae is the causative agent of gonorrhea and an obligate pathogen of humans. The Opa proteins of these bacteria are known to mediate attachment and internalization by host cells, including neutrophils. The Opa protein repertoire of a typical N. gonorrhoeae isolate is encoded on ~11 genes distributed throughout the chromosome and is subject to stochastic changes in expression through phase variation. Together, these characteristics make Opa proteins a critical yet unpredictable aspect of any experimental investigation into the interaction of N. gonorrhoeae with host cells. The goal of this study was to identify novel virulence factors of N. gonorrhoeae by assessing the contribution of a set of uncharacterized hydrogen peroxide-induced genes to bacterial survival against neutrophil-mediated killing. To this end, a strain harboring an engineered mutation in the NGO0322 gene was identified that exhibited increased sensitivity to neutrophil-mediated killing, enhanced internalization by neutrophils, and the ability to induce high levels of neutrophil-generated reactive oxygen species. Each of these phenotypes reverted to near wild-type levels following genetic complementation of the NGO0322 mutation. However, after immunoblot analysis of Opa proteins expressed by the isogenic parent, mutant, and genetically complemented strains, it was determined that phase variation had resulted in a disparity between the Opa profiles of these strains. To determine whether Opa phase variation, rather than NGO0322 mutation, was the cause of the observed neutrophil-related phenotypes, NGO0322 function was investigated in N. gonorrhoeae strains lacking all Opa proteins or constitutively expressing the OpaD variant. In both cases, mutation of NGO0322 did not alter survival of gonococci in the presence of neutrophils. These results demonstrate the importance of controlling for the frequent and random variation in Opa protein production by N. gonorrhoeae when investigating host cell interactions.
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Affiliation(s)
- Mark T. Anderson
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - H. Steven Seifert
- Department of Microbiology-Immunology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, United States of America
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Johswich KO, McCaw SE, Islam E, Sintsova A, Gu A, Shively JE, Gray-Owen SD. In vivo adaptation and persistence of Neisseria meningitidis within the nasopharyngeal mucosa. PLoS Pathog 2013; 9:e1003509. [PMID: 23935487 PMCID: PMC3723569 DOI: 10.1371/journal.ppat.1003509] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2013] [Accepted: 06/04/2013] [Indexed: 12/13/2022] Open
Abstract
Neisseria meningitidis (Nme) asymptomatically colonizes the human nasopharynx, yet can initiate rapidly-progressing sepsis and meningitis in rare instances. Understanding the meningococcal lifestyle within the nasopharyngeal mucosa, a phase of infection that is prerequisite for disease, has been hampered by the lack of animal models. Herein, we compare mice expressing the four different human carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) that can bind the neisserial Opa protein adhesins, and find that expression of human CEACAM1 is necessary and sufficient to establish intranasal colonization. During infection, in vivo selection for phase variants expressing CEACAM1-specific Opa proteins occurs, allowing mucosal attachment and entry into the subepithelial space. Consistent with an essential role for Opa proteins in this process, Opa-deficient meningococci were unable to colonize the CEACAM1-humanized mice. While simple Opa-mediated attachment triggered an innate response regardless of meningococcal viability within the inoculum, persistence of viable Opa-expressing bacteria within the CEACAM1-humanized mice was required for a protective memory response to be achieved. Parenteral immunization with a capsule-based conjugate vaccine led to the accumulation of protective levels of Nme-specific IgG within the nasal mucus, yet the sterilizing immunity afforded by natural colonization was instead conferred by Nme-specific IgA without detectable IgG. Considered together, this study establishes that the availability of CEACAM1 helps define the exquisite host specificity of this human-restricted pathogen, displays a striking example of in vivo selection for the expression of desirable Opa variants, and provides a novel model in which to consider meningococcal infection and immunity within the nasopharyngeal mucosa. Neisseria meningitidis (Nme), a common cause of bacterial meningitis, are carried asymptomatically in the nasopharynx by a substantial proportion of healthy individuals. Their strict adaptation to the human as host has so far impeded the development of animal models to study the meningococcal lifestyle in vivo. While several human CEACAMs are recognized by the neisserial Opa protein adhesins, we show here that the expression of human CEACAM1 in transgenic mice is necessary and sufficient to allow nasal colonization by Nme. The dependence on human CEACAM1 is attributable to the Opa proteins, since intranasal infection with Opa-negative colonies of Nme selects for bacteria expressing Opa proteins, and genetically Opa-deficient meningococci are unable to colonize these animals. We use this new mouse model to examine how innate immune factors such as neutrophils and complement limit colonization. Furthermore, we compare how adaptive responses elicited by colonization and those generated by parenteral vaccination differentially confer sterilizing immunity. Together, this work provides the first evidence of the critical nature of Opa-CEACAM1 binding in vivo, demonstrates that this is a major determinant of the host restriction by Nme, and reveals a clear disparity between immune correlates of sterilizing immunity conferred by natural colonization versus parenteral immunization.
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Affiliation(s)
- Kay O Johswich
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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Abstract
The outer membrane of Gram-negative bacteria contains a large number of channel-forming proteins, porins, for the uptake of small nutrient molecules. Neisseria gonorrhoeae PorBIA (PorB of serotype A) are associated with disseminating diseases and mediate a rapid bacterial invasion into host cells in a phosphate-sensitive manner. To gain insights into this structure-function relationship we analysed PorBIA by X-ray crystallography in the presence of phosphate and ATP. The structure of PorBIA in the complex solved at a resolution of 3.3 Å (1 Å=0.1 nm) displays a surplus of positive charges inside the channel. ATP ligand-binding in the channel is co-ordinated by the positively charged residues of the channel interior. These residues ligate the aromatic, sugar and pyrophosphate moieties of the ligand. Two phosphate ions were observed in the structure, one of which clamped by two arginine residues (Arg92 and Arg124) localized at the extraplasmic channel exit. A short β-bulge in β2-strand together with the long L3 loop narrow the barrel diameter significantly and further support substrate specificity through hydrogen bond interactions. Interestingly the structure also comprised a small peptide as a remnant of a periplasmic protein which physically links porin molecules to the peptidoglycan network. To test the importance of Arg92 on bacterial invasion the residue was mutated. In vivo assays of bacteria carrying a R92S mutation confirmed the importance of this residue for host-cell invasion. Furthermore systematic sequence and structure comparisons of PorBIA from Neisseriaceae indicated Arg92 to be unique in disseminating N. gonorrhoeae thereby possibly distinguishing invasion-promoting porins from other neisserial porins.
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Yu Q, Chow EMC, McCaw SE, Hu N, Byrd D, Amet T, Hu S, Ostrowski MA, Gray-Owen SD. Association of Neisseria gonorrhoeae Opa(CEA) with dendritic cells suppresses their ability to elicit an HIV-1-specific T cell memory response. PLoS One 2013; 8:e56705. [PMID: 23424672 PMCID: PMC3570455 DOI: 10.1371/journal.pone.0056705] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Accepted: 01/16/2013] [Indexed: 01/07/2023] Open
Abstract
Infection with Neisseria gonorrhoeae (N. gonorrhoeae) can trigger an intense local inflammatory response at the site of infection, yet there is little specific immune response or development of immune memory. Gonococcal surface epitopes are known to undergo antigenic variation; however, this is unlikely to explain the weak immune response to infection since individuals can be re-infected by the same serotype. Previous studies have demonstrated that the colony opacity-associated (Opa) proteins on the N. gonorrhoeae surface can bind human carcinoembryonic antigen-related cellular adhesion molecule 1 (CEACAM1) on CD4⁺ T cells to suppress T cell activation and proliferation. Interesting in this regard, N. gonorrhoeae infection is associated with impaired HIV-1 (human immunodeficiency virus type 1)-specific cytotoxic T-lymphocyte (CTL) responses and with transient increases in plasma viremia in HIV-1-infected patients, suggesting that N. gonorrhoeae may also subvert immune responses to co-pathogens. Since dendritic cells (DCs) are professional antigen presenting cells (APCs) that play a key role in the induction of an adaptive immune response, we investigated the effects of N. gonorrhoeae Opa proteins on human DC activation and function. While morphological changes reminiscent of DC maturation were evident upon N. gonorrhoeae infection, we observed a marked downregulation of DC maturation marker CD83 when the gonococci expressing CEACAM1-specific Opa(CEA), but not other Opa variants. Consistent with a gonococcal-induced defect in maturation, Opa(CEA) binding to CEACAM1 reduced the DCs' capacity to stimulate an allogeneic T cell proliferative response. Moreover, Opa(CEA)-expressing N. gonorrhoeae showed the potential to impair DC-dependent development of specific adaptive immunity, since infection with Opa(CEA)-positive gonococci suppressed the ability of DCs to stimulate HIV-1-specific memory CTL responses. These results reveal a novel mechanism to explain why infection of N. gonorrhoeae fails to trigger an effective specific immune response or develop immune memory, and may affect the potent synergy between gonorrhea and HIV-1 infection.
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Affiliation(s)
- Qigui Yu
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Edith M. C. Chow
- Department of Molecular Genetics, and 3Clinical Sciences Division, University of Toronto, Toronto, Ontario, Canada
| | - Shannon E. McCaw
- Department of Molecular Genetics, and 3Clinical Sciences Division, University of Toronto, Toronto, Ontario, Canada
| | - Ningjie Hu
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Daniel Byrd
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Tohti Amet
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Sishun Hu
- Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | | | - Scott D. Gray-Owen
- Department of Molecular Genetics, and 3Clinical Sciences Division, University of Toronto, Toronto, Ontario, Canada
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Bartsch P, Walter C, Selenschik P, Honigmann A, Wagner R. Horizontal Bilayer for Electrical and Optical Recordings. MATERIALS 2012. [PMCID: PMC5449052 DOI: 10.3390/ma5122705] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Philipp Bartsch
- Biophysics, Department of Biology/Chemistry, University Osnabrueck, Barbarastr. 13, Osnabrueck 49076, Germany; E-Mails: (P.B.); (C.W.); (P.S.); (A.H.)
- Ionovation GmbH, Westerbreite 7, Osnabrueck 49084, Germany
| | - Claudius Walter
- Biophysics, Department of Biology/Chemistry, University Osnabrueck, Barbarastr. 13, Osnabrueck 49076, Germany; E-Mails: (P.B.); (C.W.); (P.S.); (A.H.)
- Ionovation GmbH, Westerbreite 7, Osnabrueck 49084, Germany
| | - Philipp Selenschik
- Biophysics, Department of Biology/Chemistry, University Osnabrueck, Barbarastr. 13, Osnabrueck 49076, Germany; E-Mails: (P.B.); (C.W.); (P.S.); (A.H.)
| | - Alf Honigmann
- Biophysics, Department of Biology/Chemistry, University Osnabrueck, Barbarastr. 13, Osnabrueck 49076, Germany; E-Mails: (P.B.); (C.W.); (P.S.); (A.H.)
| | - Richard Wagner
- Biophysics, Department of Biology/Chemistry, University Osnabrueck, Barbarastr. 13, Osnabrueck 49076, Germany; E-Mails: (P.B.); (C.W.); (P.S.); (A.H.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +49-541-969-2398; Fax: +49-541-969-2243
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Construction and characterization of a derivative of Neisseria gonorrhoeae strain MS11 devoid of all opa genes. J Bacteriol 2012; 194:6468-78. [PMID: 23002223 DOI: 10.1128/jb.00969-12] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To better understand the role of Opa in gonococcal infections, we created and characterized a derivative of MS11 (MS11Δopa) that had the coding sequence for all 11 Opa proteins deleted. The MS11Δopa bacterium lost the ability to bind to purified lipooligosaccharide (LOS). While nonpiliated MS11Δopa and nonpiliated Opa-expressing MS11 cells grew at the same rate, nonpiliated MS11Δopa cells rarely formed clumps of more than four bacteria when grown in broth with vigorous shaking. Using flow cytometry analysis, we demonstrated that MS11Δopa produced a homogeneous population of bacteria that failed to bind monoclonal antibody (MAb) 4B12, a MAb specific for Opa. Opa-expressing MS11 cells consisted of two predominant populations, where ∼85% bound MAb 4B12 to a significant level and the other population bound little if any MAb. Approximately 90% of bacteria isolated from a phenotypically Opa-negative colony (a colony that does not refract light) failed to bind MAb 4B12; the remaining 10% bound MAb to various degrees. Piliated MS11Δopa cells formed dispersed microcolonies on ME180 cells which were visually distinct from those of piliated Opa-expressing MS11 cells. When Opa expression was reintroduced into MS11Δopa, the adherence ability of the strain recovered to wild-type levels. These data indicate that Opa contributes to both bacterium-bacterium and bacterium-host cell interactions.
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So NSY, Ostrowski MA, Gray-Owen SD. Vigorous response of human innate functioning IgM memory B cells upon infection by Neisseria gonorrhoeae. THE JOURNAL OF IMMUNOLOGY 2012; 188:4008-22. [PMID: 22427638 DOI: 10.4049/jimmunol.1100718] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Neisseria gonorrhoeae, the cause of the sexually transmitted infection gonorrhea, elicits low levels of specific Ig that decline rapidly after the bacteria are cleared. Reinfection with the same serovar can occur, and prior gonococcal infection does not alter the Ig response upon subsequent exposure, suggesting that protective immunity is not induced. The mucosal Ig response apparent during gonorrhea does not correlate with that observed systemically, leading to a suggestion that it is locally generated. In considering whether N. gonorrhoeae directly influences B cells, we observed that gonococcal infection prolonged viability of primary human B cells in vitro and elicited robust activation and vigorous proliferative responses in the absence of T cells. Furthermore, we observed the specific expansion of IgD(+)CD27(+) B cells in response to gonococcal infection. These cells are innate in function, conferring protection against diverse microbes by producing low-affinity, broadly reactive IgM without inducing classical immunologic memory. Although gonococcal infection of B cells produced small amounts of gonococcal-specific IgM, IgM specific for irrelevant Ags were also produced, suggesting a broad, polyspecific Ig response. The gonococci were effectively bound and engulfed by B cells. TLR9-inhibitory CpGs blocked B cell responses, indicating that intracellular bacterial degradation allows for innate immune detection within the phagolysosome. To our knowledge, this is the first report of a bacterial pathogen having specific affinity for the human IgM memory B cells, driving their potent activation and polyclonal Ig response. This unfocused T-independent response explains the localized Ig response that occurs, despite an absence of immunologic memory elicited during gonorrhea.
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Affiliation(s)
- Nancy S Y So
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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26
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Jamet A, Frapy E, Schneider D, Nassif X, Martin P. A cell-contact-regulated operon is involved in genetic variability in Neisseria meningitidis. Res Microbiol 2012; 163:192-9. [PMID: 22212726 DOI: 10.1016/j.resmic.2011.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Accepted: 12/03/2011] [Indexed: 11/30/2022]
Abstract
The ability of Neisseria meningitidis to establish efficient interaction with host cells is crucial for its survival. We recently demonstrated that an entire operon containing genes NMA1802 to NMA1806 was overexpressed during the early stage of the colonization process. In this work, we investigated whether upregulation of the expression of this operon facilitated the ability of N. meningitidis to adapt to growth on host cells. Using a strain displaying an inducible operon, we demonstrated that the NMA1802-NMA1806 cell-contact-regulated operon could potentially improve the adaptability of meningococcus during growth on the cell surface through enhanced generation of variants.
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Affiliation(s)
- Anne Jamet
- Institut National de la Santé et de la Recherche Médicale, U1002, F-75015 Paris, France.
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Hsieh D, Davis A, Nanda V. A knowledge-based potential highlights unique features of membrane α-helical and β-barrel protein insertion and folding. Protein Sci 2011; 21:50-62. [PMID: 22031179 DOI: 10.1002/pro.758] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Revised: 09/06/2011] [Accepted: 10/19/2011] [Indexed: 12/16/2022]
Abstract
Outer membrane β-barrel proteins differ from α-helical inner membrane proteins in lipid environment, secondary structure, and the proposed processes of folding and insertion. It is reasonable to expect that outer membrane proteins may contain primary sequence information specific for their folding and insertion behavior. In previous work, a depth-dependent insertion potential, E(z) , was derived for α-helical inner membrane proteins. We have generated an equivalent potential for TM β-barrel proteins. The similarities and differences between these two potentials provide insight into unique aspects of the folding and insertion of β-barrel membrane proteins. This potential can predict orientation within the membrane and identify functional residues involved in intermolecular interactions.
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Affiliation(s)
- Daniel Hsieh
- BioMaPS Institute and the Graduate Program in Computational Biology and Molecular Biophysics, Rutgers University, Piscataway, NJ 08854, USA
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Griffiths NJ, Hill DJ, Borodina E, Sessions RB, Devos NI, Feron CM, Poolman JT, Virji M. Meningococcal surface fibril (Msf) binds to activated vitronectin and inhibits the terminal complement pathway to increase serum resistance. Mol Microbiol 2011; 82:1129-49. [PMID: 22050461 DOI: 10.1111/j.1365-2958.2011.07876.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Complement evasion is an important survival strategy of Neisseria meningitidis (Nm) during colonization and infection. Previously, we have shown that Nm Opc binds to serum vitronectin to inhibit complement-mediated killing. In this study, we demonstrate meningococcal interactions with vitronectin via a novel adhesin, Msf (meningococcal surface fibril, previously NhhA or Hsf). As with Opc, Msf binds preferentially to activated vitronectin (aVn), engaging at its N-terminal region but the C-terminal heparin binding domain may also participate. However, unlike Opc, the latter binding is not heparin-mediated. By binding to aVn, Msf or Opc can impart serum resistance, which is further increased in coexpressers, a phenomenon dependent on serum aVn concentrations. The survival fitness of aVn-binding derivatives was evident from mixed population studies, in which msf/opc mutants were preferentially depleted. In addition, using vitronectin peptides to block Msf-aVn interactions, aVn-induced inhibition of lytic C5b-9 formation and of serum killing could be reversed. As Msf-encoding gene is ubiquitous in the meningococcal strains examined and is expressed in vivo, serum resistance via Msf may be of significance to meningococcal pathogenesis. The data imply that vitronectin binding may be an important strategy for the in vivo survival of Nm for which the bacterium has evolved redundant mechanisms.
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Affiliation(s)
- Natalie J Griffiths
- Schools of Cellular & Molecular Medicine, University of Bristol, Bristol BS8 1TD, UK
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Genotypic and phenotypic modifications of Neisseria meningitidis after an accidental human passage. PLoS One 2011; 6:e17145. [PMID: 21386889 PMCID: PMC3046118 DOI: 10.1371/journal.pone.0017145] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Accepted: 01/11/2011] [Indexed: 01/27/2023] Open
Abstract
A scientist in our laboratory was accidentally infected while working with Z5463, a Neisseria meningitidis serogroup A strain. She developed severe symptoms (fever, meningism, purpuric lesions) that fortunately evolved with antibiotic treatment to complete recovery. Pulse-field gel electrophoresis confirmed that the isolate obtained from the blood culture (Z5463BC) was identical to Z5463, more precisely to a fourth subculture of this strain used the week before the contamination (Z5463PI). In order to get some insights into genomic modifications that can occur in vivo, we sequenced these three isolates. All the strains contained a mutated mutS allele and therefore displayed an hypermutator phenotype, consistent with the high number of mutations (SNP, Single Nucleotide Polymorphism) detected in the three strains. By comparing the number of SNP in all three isolates and knowing the number of passages between Z5463 and Z5463PI, we concluded that around 25 bacterial divisions occurred in the human body. As expected, the in vivo passage is responsible for several modifications of phase variable genes. This genomic study has been completed by transcriptomic and phenotypic studies, showing that the blood strain used a different haemoglobin-linked iron receptor (HpuA/B) than the parental strains (HmbR). Different pilin variants were found after the in vivo passage, which expressed different properties of adhesion. Furthermore the deletion of one gene involved in LOS biosynthesis (lgtB) results in Z5463BC expressing a different LOS than the L9 immunotype of Z2491. The in vivo passage, despite the small numbers of divisions, permits the selection of numerous genomic modifications that may account for the high capacity of the strain to disseminate.
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Dobson-Belaire WN, Rebbapragada A, Malott RJ, Yue FY, Kovacs C, Kaul R, Ostrowski MA, Gray-Owen SD. Neisseria gonorrhoeae effectively blocks HIV-1 replication by eliciting a potent TLR9-dependent interferon-α response from plasmacytoid dendritic cells. Cell Microbiol 2010; 12:1703-17. [DOI: 10.1111/j.1462-5822.2010.01502.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Sa E Cunha C, Griffiths NJ, Virji M. Neisseria meningitidis Opc invasin binds to the sulphated tyrosines of activated vitronectin to attach to and invade human brain endothelial cells. PLoS Pathog 2010; 6:e1000911. [PMID: 20502634 PMCID: PMC2873925 DOI: 10.1371/journal.ppat.1000911] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Accepted: 04/16/2010] [Indexed: 11/18/2022] Open
Abstract
The host vasculature is believed to constitute the principal route of dissemination of Neisseria meningitidis (Nm) throughout the body, resulting in septicaemia and meningitis in susceptible humans. In vitro, the Nm outer membrane protein Opc can enhance cellular entry and exit, utilising serum factors to anchor to endothelial integrins; but the mechanisms of binding to serum factors are poorly characterised. This study demonstrates that Nm Opc expressed in acapsulate as well as capsulate bacteria can increase human brain endothelial cell line (HBMEC) adhesion and entry by first binding to serum vitronectin and, to a lesser extent, fibronectin. This study also demonstrates that Opc binds preferentially to the activated form of human vitronectin, but not to native vitronectin unless the latter is treated to relax its closed conformation. The direct binding of vitronectin occurs at its Connecting Region (CR) requiring sulphated tyrosines Y(56) and Y(59). Accordingly, Opc/vitronectin interaction could be inhibited with a conformation-dependent monoclonal antibody 8E6 that targets the sulphotyrosines, and with synthetic sulphated (but not phosphorylated or unmodified) peptides spanning the vitronectin residues 43-68. Most importantly, the 26-mer sulphated peptide bearing the cell-binding domain (45)RGD(47) was sufficient for efficient meningococcal invasion of HBMECs. To our knowledge, this is the first study describing the binding of a bacterial adhesin to sulphated tyrosines of the host receptor. Our data also show that a single region of Opc is likely to interact with the sulphated regions of both vitronectin and of heparin. As such, in the absence of heparin, Opc-expressing Nm interact directly at the CR but when precoated with heparin, they bind via heparin to the heparin-binding domain of the activated vitronectin, although with a lower affinity than at the CR. Such redundancy suggests the importance of Opc/vitronectin interaction in meningococcal pathogenesis and may enable the bacterium to harness the benefits of the physiological processes in which the host effector molecule participates.
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Affiliation(s)
- Claudia Sa E Cunha
- Department of Cellular and Molecular Medicine, School of Medical Sciences, University of Bristol, Bristol, United Kingdom
| | - Natalie J. Griffiths
- Department of Cellular and Molecular Medicine, School of Medical Sciences, University of Bristol, Bristol, United Kingdom
| | - Mumtaz Virji
- Department of Cellular and Molecular Medicine, School of Medical Sciences, University of Bristol, Bristol, United Kingdom
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Weyand NJ, Calton CM, Higashi DL, Kanack KJ, So M. Presenilin/gamma-secretase cleaves CD46 in response to Neisseria infection. THE JOURNAL OF IMMUNOLOGY 2009; 184:694-701. [PMID: 20018629 DOI: 10.4049/jimmunol.0900522] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CD46 is a type I transmembrane protein with complement and T cell regulatory functions in human cells. CD46 has signaling and receptor properties in immune and nonimmune cells, many of which are dependent on the expression of cytoplasmic tail (cyt) isoforms cyt1 or cyt2. Little is known about how cyt1 and cyt2 mediate cellular responses. We show that CD46-cyt1 and CD46-cyt2 are substrates for presenilin/gamma-secretase (PS/gammaS), an endogenous protease complex that regulates many important signaling proteins through proteolytic processing. PS/gammaS processing of CD46 releases immunoprecipitable cyt1 and cyt2 tail peptides into the cell, is blocked by chemical inhibitors, and is prevented in dominant negative presenilin mutant cell lines. Two human pathogens, Neisseria gonorrhoeae and Neisseria meningitidis, stimulate PS/gammaS processing of CD46-cyt1 and CD46-cyt2. This stimulation requires type IV pili and PilT, the type IV pilus retraction motor, implying that mechanotransduction plays a role in this event. We present a model for PS/gammaS processing of CD46 that provides a mechanism by which signals are transduced via the cyt1 and cyt2 tails to regulate CD46-dependent cellular responses. Our findings have broad implications for understanding the full range of CD46 functions in infection and noninfection situations.
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Affiliation(s)
- Nathan J Weyand
- BIO5 Institute, University of Arizona, Tucson, AZ 85721, USA.
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Higashi DL, Zhang GH, Biais N, Myers LR, Weyand NJ, Elliott DA, So M. Influence of type IV pilus retraction on the architecture of the Neisseria gonorrhoeae-infected cell cortex. MICROBIOLOGY-SGM 2009; 155:4084-4092. [PMID: 19762436 DOI: 10.1099/mic.0.032656-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Early in infection, Neisseria gonorrhoeae can be observed to attach to the epithelial cell surface as microcolonies and induce dramatic changes to the host cell cortex. We tested the hypothesis that type IV pili (Tfp) retraction plays a role in the ultrastructure of both the host cell cortex and the bacterial microcolony. Using serial ultrathin sectioning, transmission electron microscopy and 3D reconstruction of serial 2D images, we have obtained what we believe to be the first 3D reconstructions of the N. gonorrhoeae-host cell interface, and determined the architecture of infected cell microvilli as well as the attached microcolony. Tfp connect both wild-type (wt) and Tfp retraction-deficient bacteria with each other, and with the host cell membrane. Tfp fibres and microvilli form a lattice in the wt microcolony and at its periphery. Wt microcolonies induce microvilli formation and increases of surface area, leading to an approximately ninefold increase in the surface area of the host cell membrane at the site of attachment. In contrast, Tfp retraction-deficient microcolonies do not affect these parameters. Wt microcolonies had a symmetrical, dome-shaped structure with a circular 'footprint', while Tfp retraction-deficient microcolonies were notably less symmetrical. These findings support a major role for Tfp retraction in microvilli and microcolony architecture. They are consistent with the biophysical attributes of Tfp and the effects of Tfp retraction on epithelial cell signalling.
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Affiliation(s)
- Dustin L Higashi
- Department of Immunobiology and the BIO5 Institute, University of Arizona, Tucson, AZ, USA
| | - Gina H Zhang
- Department of Cell Biology and Anatomy, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - Nicolas Biais
- Department of Biological Sciences, Columbia University, New York, USA
| | - Lauren R Myers
- Department of Immunobiology and the BIO5 Institute, University of Arizona, Tucson, AZ, USA
| | - Nathan J Weyand
- Department of Immunobiology and the BIO5 Institute, University of Arizona, Tucson, AZ, USA
| | - David A Elliott
- Department of Cell Biology and Anatomy, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - Magdalene So
- Department of Immunobiology and the BIO5 Institute, University of Arizona, Tucson, AZ, USA
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Carbonnelle E, Hill DJ, Morand P, Griffiths NJ, Bourdoulous S, Murillo I, Nassif X, Virji M. Meningococcal interactions with the host. Vaccine 2009; 27 Suppl 2:B78-89. [PMID: 19481311 DOI: 10.1016/j.vaccine.2009.04.069] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Neisseria meningitidis interacts with host tissues through hierarchical, concerted and co-ordinated actions of a number of adhesins; many of which undergo antigenic and phase variation, a strategy that helps immune evasion. Three major structures, pili, Opa and Opc predominantly influence bacterial adhesion to host cells. Pili and Opa proteins also determine host and tissue specificity while Opa and Opc facilitate efficient cellular invasion. Recent studies have also implied a role of certain adhesin-receptor pairs in determining increased host susceptibility to infection. This chapter examines our current knowledge of meningococcal adhesion and invasion mechanisms particularly related to human epithelial and endothelial cells which are of primary importance in the disease process.
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Affiliation(s)
- Etienne Carbonnelle
- INSERM, unité 570, Université Paris Descartes, 156 rue de Vaugirard, Paris 75015, France
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Sa E Cunha C, Griffiths NJ, Murillo I, Virji M. Neisseria meningitidis Opc invasin binds to the cytoskeletal protein alpha-actinin. Cell Microbiol 2009; 11:389-405. [PMID: 19016781 PMCID: PMC2688670 DOI: 10.1111/j.1462-5822.2008.01262.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2008] [Revised: 10/14/2008] [Accepted: 10/28/2008] [Indexed: 12/12/2022]
Abstract
Neisseria meningitidis Opc protein is an effective invasin for human endothelial cells. We have investigated novel human endothelial receptors targeted by Opc and observed that Opc-expressing bacteria interacted with a 100 kDa protein in whole-cell lysates of human endothelial and epithelial cells. The identity of the protein was established as alpha-actinin by mass spectrometry. Opc expression was essential for the recognition of alpha-actinin whether provided in a purified form or in cell extracts. The interaction of the two proteins did not involve intermediate molecules. As there was no demonstrable expression of alpha-actinin on the surfaces of any of the eight cell lines studied, the likelihood of the interactions after meningococcal internalization was examined. Confocal imaging demonstrated considerable colocalization of N. meningitidis with alpha-actinin especially after a prolonged period of internalization. This may imply that bacteria and alpha-actinin initially occur in separate compartments and co-compartmentalization occurs progressively over the 8 h infection period used. In conclusion, these studies have identified a novel and an intracellular target for the N. meningitidis Opc invasin. Since alpha-actinin is a modulator of a variety of signalling pathways and of cytoskeletal functions, its targeting by Opc may enable bacteria to survive/translocate across endothelial barriers.
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Affiliation(s)
- Claudia Sa E Cunha
- Department of Cellular and Molecular Medicine, School of Medical Sciences, University of BristolBristol BS8 1TD, UK
| | - Natalie J Griffiths
- Department of Cellular and Molecular Medicine, School of Medical Sciences, University of BristolBristol BS8 1TD, UK
| | - Isabel Murillo
- Department of Cellular and Molecular Medicine, School of Medical Sciences, University of BristolBristol BS8 1TD, UK
| | - Mumtaz Virji
- Department of Cellular and Molecular Medicine, School of Medical Sciences, University of BristolBristol BS8 1TD, UK
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Higashi DL, Lee SW, Snyder A, Weyand NJ, Bakke A, So M. Dynamics of Neisseria gonorrhoeae attachment: microcolony development, cortical plaque formation, and cytoprotection. Infect Immun 2007; 75:4743-53. [PMID: 17682045 PMCID: PMC2044525 DOI: 10.1128/iai.00687-07] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Neisseria gonorrhoeae is the bacterium that causes gonorrhea, a major sexually transmitted disease and a significant cofactor for human immunodeficiency virus transmission. The retactile N. gonorrhoeae type IV pilus (Tfp) mediates twitching motility and attachment. Using live-cell microscopy, we reveal for the first time the dynamics of twitching motility by N. gonorrhoeae in its natural environment, human epithelial cells. Bacteria aggregate into microcolonies on the cell surface and induce a massive remodeling of the microvillus architecture. Surprisingly, the microcolonies are motile, and they fuse to form progressively larger structures that undergo rapid reorganization, suggesting that bacteria communicate with each other during infection. As reported, actin plaques form beneath microcolonies. Here, we show that cortical plaques comigrate with motile microcolonies. These activities are dependent on pilT, the Tfp retraction locus. Cultures infected with a pilT mutant have significantly higher numbers of apoptotic cells than cultures infected with the wild-type strain. Inducing pilT expression with isopropyl-beta-D-thiogalactopyranoside partially rescues cells from infection-induced apoptosis, demonstrating that Tfp retraction is intrinsically cytoprotective for the host. Tfp-mediated attachment is therefore a continuum of microcolony motility and force stimulation of host cell signaling, leading to a cytoprotective effect.
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Affiliation(s)
- Dustin L Higashi
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd., Portland, Oregon 97239, USA
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37
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Serino L, Nesta B, Leuzzi R, Fontana MR, Monaci E, Mocca BT, Cartocci E, Masignani V, Jerse AE, Rappuoli R, Pizza M. Identification of a new OmpA-like protein in Neisseria gonorrhoeae involved in the binding to human epithelial cells and in vivo colonization. Mol Microbiol 2007; 64:1391-403. [PMID: 17542928 DOI: 10.1111/j.1365-2958.2007.05745.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Outer membrane protein As (OmpAs) are highly conserved proteins within the Enterobacteriaceae family. OmpA contributes to the maintenance of structural membrane integrity and invasion into mammalian cells. In Escherichia coli K1 OmpA also contributes to serum resistance and is involved in the virulence of the bacterium. Here we describe the identification of an OmpA-like protein in Neisseria gonorrhoeae (Ng-OmpA). We show that the gonococcal OmpA-like protein, similarly to E. coli OmpA, plays a significant role in the adhesion and invasion into human cervical carcinoma and endometrial cells and is required for entry into macrophages and intracellular survival. Furthermore, the isogenic knockout ompA mutant demonstrates reduced recovery in a mouse model of infection when compared with the wild-type strain, suggesting that Ng-OmpA plays an important role in the in vivo colonization. All together, these data suggest that the newly identified surface exposed protein Ng-OmpA represents a novel virulence factor of gonococcus.
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Affiliation(s)
- Laura Serino
- Research Centre, Novartis Vaccines, Via Fiorentina, 1, 53100 Siena, Italy.
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38
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Lee HSW, Boulton IC, Reddin K, Wong H, Halliwell D, Mandelboim O, Gorringe AR, Gray-Owen SD. Neisserial outer membrane vesicles bind the coinhibitory receptor carcinoembryonic antigen-related cellular adhesion molecule 1 and suppress CD4+ T lymphocyte function. Infect Immun 2007; 75:4449-55. [PMID: 17620353 PMCID: PMC1951172 DOI: 10.1128/iai.00222-07] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pathogenic Neisseria bacteria naturally liberate outer membrane "blebs," which are presumed to contribute to pathology, and the detergent-extracted outer membrane vesicles (OMVs) from Neisseria meningitidis are currently employed as meningococcal vaccines in humans. While the composition of these vesicles reflects the bacteria from which they are derived, the functions of many of their constituent proteins remain unexplored. The neisserial colony opacity-associated Opa proteins function as adhesins, the majority of which mediate bacterial attachment to human carcinoembryonic antigen-related cellular adhesion molecules (CEACAMs). Herein, we demonstrate that the Opa proteins within OMV preparations retain the capacity to bind the immunoreceptor tyrosine-based inhibitory motif-containing coinhibitory receptor CEACAM1. When CD4(+) T lymphocytes were exposed to OMVs from Opa-expressing bacteria, their activation and proliferation in response to a variety of stimuli were effectively halted. This potent immunosuppressive effect suggests that localized infection will generate a "zone of inhibition" resulting from the diffusion of membrane blebs into the surrounding tissues. Moreover, it demonstrates that OMV-based vaccines must be developed from strains that lack CEACAM1-binding Opa variants.
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Affiliation(s)
- Hannah S W Lee
- Department of Medical Genetics and Microbiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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Pérez RE, Lasa AM, Rodríguez RS, Menéndez EC, Suárez JG, Balaguer HD. Scale-up of recombinant Opc protein production in Escherichia coli for a meningococcal vaccine. J Biotechnol 2006; 127:109-14. [PMID: 16893582 DOI: 10.1016/j.jbiotec.2006.06.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2006] [Revised: 06/02/2006] [Accepted: 06/14/2006] [Indexed: 11/19/2022]
Abstract
Opc is an outer membrane protein from Neisseria meningitidis present in meningococcal vaccine preparations. The opc gene, codifying for this protein, was cloned in to Escherichia coli and the Opc protein was expressed under the control of a tryptophan promoter. The recombinant strain was grown in batch cultures. Opc was expressed as inclusion bodies at about 32% of the total cellular protein. We examined the scale-up culture conditions for the production of the recombinant Opc. The scale-up process was performed from 1.5 l to 50 l culture, using first, the constant power per unit of volume (P/V) as main scaling criteria, and then the oxygen mass transfer coefficient (K(L)a) scaling criteria to adjust the optimal aeration conditions. A final productivity of 52 mgl(-1)h(-1) was obtained at the 50l culture scale compared with the 49 mgl(-1)h(-1) productivity at 1.5l laboratory scale.
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Affiliation(s)
- Raúl Espinosa Pérez
- División de Desarrollo Biofarmacéutico, Centro de Ingeniería Genética y Biotecnología, Ave 31e/ 158 y 190, Apdo. Postal 6162, Cubanacán, Playa, La Habana 10600, Cuba
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40
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Simms AN, Jerse AE. In vivo selection for Neisseria gonorrhoeae opacity protein expression in the absence of human carcinoembryonic antigen cell adhesion molecules. Infect Immun 2006; 74:2965-74. [PMID: 16622235 PMCID: PMC1459723 DOI: 10.1128/iai.74.5.2965-2974.2006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The neisserial opacity (Opa) proteins are phase-variable, antigenically distinct outer membrane proteins that mediate adherence to and invasion of human cells. We previously reported that Neisseria gonorrhoeae Opa protein expression appeared to be selected for or induced during experimental murine genital tract infection. Here we further defined the kinetics of recovery of Opa variants from the lower genital tracts of female mice and investigated the basis for this initial observation. We found that the recovery of different Opa phenotypes from mice appears cyclical. Three phases of infection were defined. Following intravaginal inoculation with primarily Opa- gonococci, the majority of isolates recovered were Opa+ (early phase). A subsequent decline in the percentage of Opa+ isolates occurred in a majority of mice (middle phase) and was followed by a reemergence of Opa+ variants in mice that were infected for longer than 8 days (late phase). We showed the early phase was due to selection for preexisting Opa+ variants in the inoculum by constructing a chloramphenicol-resistant (Cm(r)) strain and following Cm(r) Opa+ populations mixed with a higher percentage of Opa- variants of the wild-type (Cm(s)) strain. Reciprocal experiments (Opa- Cm(r) gonococci spiked with Opa+ Cm(s) bacteria) were consistent with selection of Opa+ variants. Based on the absence in mice of human carcinoembryonic antigen cell adhesion molecules, the major class of Opa protein adherence receptors, we conclude the observed selection for Opa+ variants early in infection is not likely due to a specific adherence advantage and may be due to Opa-mediated evasion of innate defenses.
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Affiliation(s)
- Amy N Simms
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Rd., Bethesda, MD 20814-4799, USA
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41
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Plant L, Sundqvist J, Zughaier S, Lövkvist L, Stephens DS, Jonsson AB. Lipooligosaccharide structure contributes to multiple steps in the virulence of Neisseria meningitidis. Infect Immun 2006; 74:1360-7. [PMID: 16428785 PMCID: PMC1360357 DOI: 10.1128/iai.74.2.1360-1367.2006] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lipooligosaccharide (LOS) of Neisseria meningitidis has been implicated in meningococcal interaction with host epithelial cells and is a major factor contributing to the human proinflammatory response to meningococci. LOS mutants of the encapsulated N. meningitidis serogroup B strain NMB were used to further determine the importance of the LOS structure in in vitro adherence and invasion of human pharyngeal epithelial cells by meningococci and to study pathogenicity in a mouse (CD46 transgenic) model of meningococcal disease. The wild-type strain [NeuNAc-Galbeta-GlcNAc-Galbeta-Glcbeta-Hep2 (GlcNAc, Glcalpha) 3-deoxy-D-manno-2-octulosonic acid (KDO2)-lipid A; 1,4' bisphosphorylated], although poorly adherent, rapidly invaded an epithelial cell layer in vitro, survived and multiplied early in blood, reached the cerebrospinal fluid, and caused lethal disease in the mouse model. In contrast, the Hep2 (GlcNAc) KDO2-lipid A (pgm) mutant, which was highly adherent to cultured epithelial cells, caused significantly less bacteremia and mortality in the mouse model. The Hep2-KDO2-lipid A (rfaK) mutant was shown to be moderately adherent and to cause levels of bacteremia and mortality similar to those caused by the wild-type strain in the mouse model. The KDO2-lipid A (gmhB) mutant, which lacks the heptose disaccharide in the inner core of LOS, avidly attached to epithelial cells but was otherwise avirulent. Disease development correlated with expression of specific LOS structures and was associated with lower adherence but rapid meningococcal passage to and survival in the bloodstream, induction of proinflammatory cytokines, and the crossing of the blood-brain barrier. Taken together, the results of this study further define the importance of the LOS structure as a virulence component involved in multiple steps in the pathogenesis of N. meningitidis.
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Affiliation(s)
- Laura Plant
- Department of Medical Biochemistry and Microbiology, Biomedical Centrum, Uppsala University, PO Box 582, Uppsala, Sweden.
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42
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Leuzzi R, Serino L, Scarselli M, Savino S, Fontana MR, Monaci E, Taddei A, Fischer G, Rappuoli R, Pizza M. Ng-MIP, a surface-exposed lipoprotein of Neisseria gonorrhoeae, has a peptidyl-prolyl cis/trans isomerase (PPIase) activity and is involved in persistence in macrophages. Mol Microbiol 2006; 58:669-81. [PMID: 16238618 DOI: 10.1111/j.1365-2958.2005.04859.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Macrophage infectivity potentiators (MIPs) are a family of surface-exposed virulence factors of intracellular microorganisms such as Legionella, Chlamydia and Trypanosoma. These proteins display peptidyl-prolyl cis/trans isomerase (PPIase) activity that is inhibited by immunosuppressants FK506 and rapamycin. Here we describe the identification and characterization in Neisseria gonorrhoeae of Ng-MIP, a surface-exposed lipoprotein with high homology to MIPs. The protein is an homodimer with rapamycin-inhibited PPIase activity confirming that it is a functional member of the MIP family. A knock-out strain, generated by deletion of the mip gene in N. gonorrhoeae F62 strain, was evaluated for its role in infection of mouse and human macrophages. We show that Ng-MIP promotes the intracellular survival of N. gonorrhoeae in macrophages, highlighting a possible role of this protein in promoting the persistence of gonococcal infection.
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Affiliation(s)
- Rosanna Leuzzi
- IRIS, Chiron S.r.l., Via Fiorentina, 1, 53100 Siena, Italy
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43
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Plant LJ, Jonsson AB. Type IV pili of Neisseria gonorrhoeae influence the activation of human CD4+ T cells. Infect Immun 2006; 74:442-8. [PMID: 16369000 PMCID: PMC1346638 DOI: 10.1128/iai.74.1.442-448.2006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2005] [Revised: 09/09/2005] [Accepted: 10/13/2005] [Indexed: 11/20/2022] Open
Abstract
Neisseria gonorrhoeae is the causative agent of the sexually transmitted disease gonorrhea, and infection with this organism is typically associated with an intense inflammatory response. In many individuals, however, the infection is asymptomatic and can progress to serious secondary complications. The type IV pili of Neisseria gonorrhoeae mediate binding of the bacteria to host cells and are involved in cellular signal transduction. In these studies we have demonstrated that gonococcal pili influence human CD4+ T cells by using isogenic strains of N. gonorrhoeae with piliated and nonpiliated phenotypes. To determine the impact of piliation on the cellular status, we examined the expression of activation markers, cellular proliferation, and the production of cytokines after infection. The activation marker CD69 showed significantly increased expression on cells infected with the piliated strain, and this expression was dependent on costimulation of the T-cell receptor. Infection with piliated gonococci also altered T-cell proliferation and influenced the production of the regulatory cytokine interleukin-10. PilC, the putative pilus adhesin, was also observed to influence cellular activation but had no impact on the proliferation of cells further indicating that pilus-mediated adhesion is important in gonococcal stimulation of CD4+ T cells. These results show that the piliation status of gonococci influences CD4+ T-cell activation and that the adhesion mediated by pilus components aids in the regulation of the T-cell response to N. gonorrhoeae.
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MESH Headings
- Antigens, CD/biosynthesis
- Antigens, CD/genetics
- Antigens, Differentiation, T-Lymphocyte/biosynthesis
- Antigens, Differentiation, T-Lymphocyte/genetics
- Bacterial Adhesion/physiology
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD4-Positive T-Lymphocytes/microbiology
- Cell Proliferation
- Cells, Cultured
- Fimbriae Proteins/physiology
- Fimbriae, Bacterial/immunology
- Fimbriae, Bacterial/physiology
- Gonorrhea/immunology
- Gonorrhea/metabolism
- Humans
- Interleukin-10/biosynthesis
- Lectins, C-Type
- Lymphocyte Activation/physiology
- Neisseria gonorrhoeae/immunology
- Neisseria gonorrhoeae/physiology
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Affiliation(s)
- Laura J Plant
- Department for Medical Biochemistry and Microbiology, Biomedical Centrum, Uppsala University, PO Box 582, Uppsala, Sweden.
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44
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Morelle S, Carbonnelle E, Matic I, Nassif X. Contact with host cells induces a DNA repair system in pathogenic Neisseriae. Mol Microbiol 2005; 55:853-61. [PMID: 15661009 DOI: 10.1111/j.1365-2958.2004.04426.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
DNA repair systems play a major role in maintaining the integrity of bacterial genomes. Neisseria meningitidis, a human pathogen capable of colonizing the human nasopharynx, possesses numerous DNA repair genes but lacks inducible DNA repair systems such as the SOS response, present in most bacteria species. We recently identified a set of genes upregulated by contact with host cells. An open reading frame having high homology with the small subunit of Escherichia coli exonuclease VII (xseB) belongs to this regulon. The increased sensitivity of a mutant in this coding sequence to UV irradiation, alkylating agent and nalidixic acid demonstrates the participation of this gene in meningococcal DNA repair. In addition, the upregulation of the transcription of this open reading frame upon interaction of N. meningitidis with host cells increased not only the bacterial ability to repair its DNA but also the rate of phase variation by frameshifting. Together these data demonstrate that N. meningitidis possesses an inducible DNA repair system that might be used by the bacteria to adapt to its niches when it is colonizing a new host.
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Affiliation(s)
- Sandrine Morelle
- INSERM U570, Faculté Necker-Enfants Malades, Université René Descartes, 156 rue de Vaugirard, 75015 Paris, France
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45
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Moore J, Bailey SES, Benmechernene Z, Tzitzilonis C, Griffiths NJE, Virji M, Derrick JP. Recognition of saccharides by the OpcA, OpaD, and OpaB outer membrane proteins from Neisseria meningitidis. J Biol Chem 2005; 280:31489-97. [PMID: 16006553 DOI: 10.1074/jbc.m506354200] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The adhesion of the pathogen Neisseria meningitidis to host cell surface proteoglycan, mediated by the integral outer membrane proteins OpcA and Opa, plays an important part in the processes of colonization and invasion by the bacterium. The precise specificities of the OpcA and Opa proteins are, however, unknown. Here we use a fluorescence-based binding assay to show that both proteins bind to mono- and disaccharides with high affinity. Binding of saccharides caused a quench in the intrinsic fluorescence emission of both proteins, and mutation of selected Tyr residues within the external loop regions caused a substantial decrease in fluorescence. We suggest that the intrinsic fluorescence arises from resonance energy transfer from Tyr to Trp residues in the beta-barrel portion of the structure. OpcA bound sialic acid with a Kd of 0.31 microM and was shown to be specific for pyranose saccharides. The binding specificities of two different Opa proteins were compared; unlike OpcA, neither protein bound to monosaccharides, but both bound to maltose, lactose, and sialic acid-containing oligosaccharides, with Kd values in the micromolar range. OpaB had a 10-fold higher affinity for sialic acid-containing ligands than OpaD as a result of the mutation Y165V, which was shown to restore this specificity to OpaD. Finally, the OpcA- and Opa-dependent adhesion of meningococci to epithelial cells was shown to be partially inhibited by exogenously added sialic acid and maltose. The results show that OpcA and the Opa proteins can be thought of as outer membrane lectins and that simple saccharides can modulate their recognition of complex proteoglycan receptors.
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Affiliation(s)
- Jeremy Moore
- Faculty of Life Sciences, University of Manchester, Manchester, M60 1QD United Kingdom
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46
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Estabrook MM, Jack DL, Klein NJ, Jarvis GA. Mannose-binding lectin binds to two major outer membrane proteins, opacity protein and porin, of Neisseria meningitidis. THE JOURNAL OF IMMUNOLOGY 2004; 172:3784-92. [PMID: 15004183 DOI: 10.4049/jimmunol.172.6.3784] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Human mannose-binding lectin (MBL) provides a first line of defense against microorganisms by complement activation and/or opsonization in the absence of specific Ab. This serum collectin has been shown to activate complement when bound to repeating sugar moieties on several microorganisms, including encapsulated serogroup B and C meningococci, which leads to increased bacterial killing. In the present study, we sought to identify the meningococcal cell surface components to which MBL bound and to characterize such binding. Outer membrane complex containing both lipooligosaccharide (LOS) and proteins and LOS from Neisseria meningitidis were examined for MBL binding by dot blot and ELISA. MBL bound outer membrane complex but not LOS. The binding to bacteria by whole-cell ELISA did not require calcium and was not inhibited by N-acetyl-glucosamine or mannose. With the use of SDS-PAGE, immunoblot analysis, and mAbs specific for meningococcal opacity (Opa) proteins and porin proteins, we determined that MBL bound to Opa and porin protein B (porB). The N-terminal amino acid sequences of the two MBL binding proteins confirmed Opa and PorB. Purified PorB inhibited the binding of MBL to meningococci. Escherichia coli with surface-expressed gonococcal Opa bound significantly more MBL than did the control strain. The binding of human factor H to purified PorB was markedly inhibited by MBL in a dose-dependent manner. Meningococci incubated with human serum bound MBL as detected by ELISA. We conclude that MBL binds to meningococci by a novel target recognition of two nonglycosylated outer membrane proteins, Opa and PorB.
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Affiliation(s)
- Michele M Estabrook
- Center for Immunochemistry and Veterans Affairs Medical Center, San Francisco, CA 94121, USA.
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47
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Dunn KLR, Farrant JL, Langford PR, Kroll JS. Bacterial [Cu,Zn]-cofactored superoxide dismutase protects opsonized, encapsulated Neisseria meningitidis from phagocytosis by human monocytes/macrophages. Infect Immun 2003; 71:1604-7. [PMID: 12595487 PMCID: PMC148830 DOI: 10.1128/iai.71.3.1604-1607.2003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Superoxide dismutase cofactored by copper and zinc ([Cu,Zn]-SOD) contributes to the protection of opsonized serogroup B Neisseria meningitidis against phagocytosis by human monocytes/macrophages, with sodC mutant organisms being endocytosed in significantly higher numbers than are wild-type organisms. The influence of [Cu,Zn]-SOD was found to be exerted at the stage of phagocytosis, rather than at earlier (modulating surface association) or later (intracellular killing) stages.
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Affiliation(s)
- Kate L R Dunn
- Molecular Infectious Diseases Group, Department of Paediatrics, Faculty of Medicine, Imperial College, St. Mary's Hospital Campus, London W2 1PG, United Kingdom
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48
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Unkmeir A, Latsch K, Dietrich G, Wintermeyer E, Schinke B, Schwender S, Kim KS, Eigenthaler M, Frosch M. Fibronectin mediates Opc-dependent internalization of Neisseria meningitidis in human brain microvascular endothelial cells. Mol Microbiol 2002; 46:933-46. [PMID: 12421301 DOI: 10.1046/j.1365-2958.2002.03222.x] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
A central step in the pathogenesis of bacterial meningitis caused by Neisseria meningitidis (the meningococcus) is the interaction of the bacteria with cells of the blood-brain barrier. In the present study, we analysed the invasive potential of two strains representing hypervirulent meningococcal lineages of the ET-5 and ET-37 complex in human brain-derived endothelial cells (HBEMCs). In contrast to previous observations made with epithelial cells and human umbilical vein-derived endothelial cells (HUVECs), significant internalization of encapsulated meningococci by HBMECs was observed. However, this uptake was found only for the ET-5 complex isolate MC 58, and not for an ET-37 complex strain. Furthermore, the uptake of meningococci by HBMECs depended on the presence of human serum, whereas serum of bovine origin did not promote the internalization of meningococci in HBMECs. By mutagenesis experiments, we demonstrate that internalization depended on the expression of the opc gene, which is present in meningococci of the ET-5 complex, but absent in ET-37 complex meningococci. Chromatographic separation of human serum proteins revealed fibronectin as the uptake-promoting serum factor, which binds to HBMECs via alpha 5 beta 1 integrin receptors. These data provide evidence for unique molecular mechanisms of the interaction of meningococci with endothelial cells of the blood-brain barrier and contribute to our understanding of the pathogenesis of meningitis caused by meningococci of different clonal lineages.
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Affiliation(s)
- Alexandra Unkmeir
- Institute of Hygiene and Microbiology, University of Würzburg, Germany.
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49
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de Jonge MI, Bos MP, Hamstra HJ, Jiskoot W, van Ulsen P, Tommassen J, van Alphen L, van der Ley P. Conformational analysis of opacity proteins from Neisseria meningitidis. EUROPEAN JOURNAL OF BIOCHEMISTRY 2002; 269:5215-23. [PMID: 12392553 DOI: 10.1046/j.1432-1033.2002.03228.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Opacity-associated (Opa) proteins are outer membrane proteins which play a critical role in the adhesion of pathogenic Neisseria spp. to epithelial and endothelial cells and polymorphonuclear neutrophils. The adherence is mainly mediated by the CD66-epitope-containing members of the carcinoembryonic-antigen family of human cell-adhesion molecules (CEACAM). For the analysis of the specific interactions of individual Opa proteins with their receptors, pure protein is needed in its native conformation. In this study, we describe the isolation and structural analysis of opacity proteins OpaJ129 and OpaB128 derived from Neisseria meningitidis strain H44/76. When the Opa proteins were produced with the phoE signal sequence in Escherichia coli, they were localized at the cell surface and the recombinant bacteria were found to specifically interact with CEACAM1. For refolding and purification, the proteins were overproduced without their signal sequences in E. coli, resulting in its cytoplasmic accumulation in the form of inclusion bodies. After solubilization of the inclusion bodies in urea, the proteins could be folded efficiently in vitro, under alkaline conditions by dilution in ethanolamine and the detergent n-dodecyl-N,N-dimethyl-1-ammonio-3-propanesulfonate (SB12). The structure of the refolded and purified proteins, determined by circular dichroism, indicated a high content of beta-sheet conformation, which is consistent with previously proposed topology models for Opa proteins. A clear difference was found between the binding of refolded vs. denatured OpaJ protein to the N-A1 domain of CEACAM1. Almost no binding was found with the denatured Opa protein, showing that the Opa-receptor interaction is conformation-dependent.
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Affiliation(s)
- Marien I de Jonge
- Laboratory of Vaccine Research, National Institute of Public Health and the Environment, RIVM Bilthoven, the Netherlands.
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Prince SM, Achtman M, Derrick JP. Crystal structure of the OpcA integral membrane adhesin from Neisseria meningitidis. Proc Natl Acad Sci U S A 2002; 99:3417-21. [PMID: 11891340 PMCID: PMC122538 DOI: 10.1073/pnas.062630899] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
OpcA is an integral outer membrane protein from Neisseria meningitidis, the causative agent of meningococcal meningitis and septicemia. It mediates the adhesion of N. meningitidis to epithelial and endothelial cells by binding to vitronectin and proteoglycan cell-surface receptors. Here, we report the determination of the crystal structure of OpcA to 2.0 A resolution. OpcA adopts a 10-stranded beta-barrel structure with extensive loop regions that protrude above the predicted surface of the membrane. The second external loop adopts an unusual conformation, traversing the axis of the beta-barrel and apparently blocking formation of a pore through the membrane. Loops 2, 3, 4, and 5 associate to form one side of a crevice in the external surface of the structure, the other side being formed by loop 1. The crevice is lined by positively charged residues and would form an ideal binding site for proteoglycan polysaccharide. The structure, therefore, suggests a model for how adhesion of this important human pathogen to proteoglycan is mediated at the molecular level.
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Affiliation(s)
- Stephen M Prince
- Department of Biomolecular Sciences, University of Manchester Institute of Science and Technology, Sackville Street, Manchester M60 1QD, United Kingdom
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