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Peters S, Mohort K, Claus H, Stigloher C, Schubert-Unkmeir A. Interaction of Neisseria meningitidis carrier and disease isolates of MenB cc32 and MenW cc22 with epithelial cells of the nasopharyngeal barrier. Front Cell Infect Microbiol 2024; 14:1389527. [PMID: 38756230 PMCID: PMC11096551 DOI: 10.3389/fcimb.2024.1389527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Accepted: 04/12/2024] [Indexed: 05/18/2024] Open
Abstract
Neisseria meningitidis (Nm, the meningococcus) is considered an asymptomatic colonizer of the upper respiratory tract and a transient member of its microbiome. It is assumed that the spread of N. meningitidis into the bloodstream occurs via transcytosis of the nasopharyngeal epithelial barrier without destroying the barrier layer. Here, we used Calu-3 respiratory epithelial cells that were grown under air-liquid-interface conditions to induce formation of pseudostratified layers and mucus production. The number of bacterial localizations in the outer mucus, as well as cellular adhesion, invasion and transmigration of different carrier and disease N. meningitidis isolates belonging to MenB:cc32 and MenW:cc22 lineages was assessed. In addition, the effect on barrier integrity and cytokine release was determined. Our findings showed that all strains tested resided primarily in the outer mucus layer after 24 h of infection (>80%). Nonetheless, both MenB:cc32 and MenW:cc22 carrier and disease isolates reached the surface of the epithelial cells and overcame the barrier. Interestingly, we observed a significant difference in the number of bacteria transmigrating the epithelial cell barrier, with the representative disease isolates being more efficient to transmigrate compared to carrier isolates. This could be attributed to the capacity of the disease isolates to invade, however could not be assigned to expression of the outer membrane protein Opc. Moreover, we found that the representative meningococcal isolates tested in this study did not damage the epithelial barrier, as shown by TEER measurement, FITC-dextran permeability assays, and expression of cell-junction components.
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Affiliation(s)
- Simon Peters
- Institute for Hygiene and Microbiology, Julius-Maximilian University Wuerzburg, Wuerzburg, Germany
| | - Katherina Mohort
- Institute for Hygiene and Microbiology, Julius-Maximilian University Wuerzburg, Wuerzburg, Germany
| | - Heike Claus
- Institute for Hygiene and Microbiology, Julius-Maximilian University Wuerzburg, Wuerzburg, Germany
| | - Christian Stigloher
- Imaging Core Facility, Biocenter, Julius-Maximilian University Wuerzburg, Wuerzburg, Germany
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2
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Rhodes KA, Rendón MA, Ma MC, Agellon A, Johnson AC, So M. Type IV pilus retraction is required for Neisseria musculi colonization and persistence in a natural mouse model of infection. mBio 2024; 15:e0279223. [PMID: 38084997 PMCID: PMC10790696 DOI: 10.1128/mbio.02792-23] [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: 10/20/2023] [Accepted: 10/25/2023] [Indexed: 01/17/2024] Open
Abstract
IMPORTANCE We describe the importance of Type IV pilus retraction to colonization and persistence by a mouse commensal Neisseria, N. musculi, in its native host. Our findings have implications for the role of Tfp retraction in mediating interactions of human-adapted pathogenic and commensal Neisseria with their human host due to the relatedness of these species.
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Affiliation(s)
- Katherine A. Rhodes
- Immunobiology Department, University of Arizona College of Medicine, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
| | - María A. Rendón
- Immunobiology Department, University of Arizona College of Medicine, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
| | - Man Cheong Ma
- Immunobiology Department, University of Arizona College of Medicine, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
| | - Al Agellon
- School of Animal and Comparative Biomedical Sciences, University of Arizona, Tucson, Arizona, USA
| | - Andrew C.E. Johnson
- Immunobiology Department, University of Arizona College of Medicine, Tucson, Arizona, USA
| | - Magdalene So
- Immunobiology Department, University of Arizona College of Medicine, Tucson, Arizona, USA
- BIO5 Institute, University of Arizona, Tucson, Arizona, USA
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3
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Vassey M, Firdaus R, Aslam A, Wheldon LM, Oldfield NJ, Ala’Aldeen DAA, Wooldridge KG. G1 Cell Cycle Arrest Is Induced by the Fourth Extracellular Loop of Meningococcal PorA in Epithelial and Endothelial Cells. Cell Microbiol 2023. [DOI: 10.1155/2023/7480033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Neisseria meningitidis is the most frequent cause of bacterial meningitis and is one of the few bacterial pathogens that can breach the blood-brain barrier (BBB). The 37/67 kDa laminin receptor (LamR) was previously identified as a receptor mediating meningococcal binding to rodent and human brain microvascular endothelial cells, which form part of the BBB. The meningococcal surface proteins PorA and PilQ were identified as ligands for this receptor. Subsequently, the fourth extracellular loop of PorA (PorA-Loop4) was identified as the LamR-binding moiety. Here, we show that PorA-Loop4 targets the 37 kDa laminin receptor precursor (37LRP) on the cell surface by demonstrating that deletion of this loop abrogates the recruitment of 37LRP under meningococcal colonies. Using a circularized peptide corresponding to PorA-Loop4, as well as defined meningococcal mutants, we demonstrate that host cell interaction with PorA-Loop4 results in perturbation of p-CDK4 and Cyclin D1. These changes in cell cycle control proteins are coincident with cellular responses including inhibition of cell migration and a G1 cell cycle arrest. Modulation of the cell cycle of host cells is likely to contribute to the pathogenesis of meningococcal disease.
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Mikucki A, McCluskey NR, Kahler CM. The Host-Pathogen Interactions and Epicellular Lifestyle of Neisseria meningitidis. Front Cell Infect Microbiol 2022; 12:862935. [PMID: 35531336 PMCID: PMC9072670 DOI: 10.3389/fcimb.2022.862935] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 02/28/2022] [Indexed: 01/17/2023] Open
Abstract
Neisseria meningitidis is a gram-negative diplococcus and a transient commensal of the human nasopharynx. It shares and competes for this niche with a number of other Neisseria species including N. lactamica, N. cinerea and N. mucosa. Unlike these other members of the genus, N. meningitidis may become invasive, crossing the epithelium of the nasopharynx and entering the bloodstream, where it rapidly proliferates causing a syndrome known as Invasive Meningococcal Disease (IMD). IMD progresses rapidly to cause septic shock and meningitis and is often fatal despite aggressive antibiotic therapy. While many of the ways in which meningococci survive in the host environment have been well studied, recent insights into the interactions between N. meningitidis and the epithelial, serum, and endothelial environments have expanded our understanding of how IMD develops. This review seeks to incorporate recent work into the established model of pathogenesis. In particular, we focus on the competition that N. meningitidis faces in the nasopharynx from other Neisseria species, and how the genetic diversity of the meningococcus contributes to the wide range of inflammatory and pathogenic potentials observed among different lineages.
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Affiliation(s)
- August Mikucki
- Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, WA, Australia
| | - Nicolie R. McCluskey
- Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, WA, Australia
- College of Science, Health, Engineering and Education, Telethon Kids Institute, Murdoch University, Perth, WA, Australia
| | - Charlene M. Kahler
- Marshall Centre for Infectious Diseases Research and Training, School of Biomedical Sciences, University of Western Australia, Perth, WA, Australia
- *Correspondence: Charlene M. Kahler,
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5
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Barnier JP, Euphrasie D, Join-Lambert O, Audry M, Schonherr-Hellec S, Schmitt T, Bourdoulous S, Coureuil M, Nassif X, El Behi M. Type IV pilus retraction enables sustained bacteremia and plays a key role in the outcome of meningococcal sepsis in a humanized mouse model. PLoS Pathog 2021; 17:e1009299. [PMID: 33592056 PMCID: PMC7909687 DOI: 10.1371/journal.ppat.1009299] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 02/26/2021] [Accepted: 01/11/2021] [Indexed: 12/17/2022] Open
Abstract
Neisseria meningitidis (the meningococcus) remains a major cause of bacterial meningitis and fatal sepsis. This commensal bacterium of the human nasopharynx can cause invasive diseases when it leaves its niche and reaches the bloodstream. Blood-borne meningococci have the ability to adhere to human endothelial cells and rapidly colonize microvessels. This crucial step enables dissemination into tissues and promotes deregulated inflammation and coagulation, leading to extensive necrotic purpura in the most severe cases. Adhesion to blood vessels relies on type IV pili (TFP). These long filamentous structures are highly dynamic as they can rapidly elongate and retract by the antagonistic action of two ATPases, PilF and PilT. However, the consequences of TFP dynamics on the pathophysiology and the outcome of meningococcal sepsis in vivo have been poorly studied. Here, we show that human graft microvessels are replicative niches for meningococci, that seed the bloodstream and promote sustained bacteremia and lethality in a humanized mouse model. Intriguingly, although pilus-retraction deficient N. meningitidis strain (ΔpilT) efficiently colonizes human graft tissue, this mutant did not promote sustained bacteremia nor induce mouse lethality. This effect was not due to a decreased inflammatory response, nor defects in bacterial clearance by the innate immune system. Rather, TFP-retraction was necessary to promote the release of TFP-dependent contacts between bacteria and, in turn, the detachment from colonized microvessels. The resulting sustained bacteremia was directly correlated with lethality. Altogether, these results demonstrate that pilus retraction plays a key role in the occurrence and outcome of meningococcal sepsis by supporting sustained bacteremia. These findings open new perspectives on the role of circulating bacteria in the pathological alterations leading to lethal sepsis.
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Affiliation(s)
- Jean-Philippe Barnier
- Université de Paris, Faculté de Médecine, Paris, France
- Institut Necker Enfants-Malades, Inserm U1151, CNRS UMR 8253, Paris, France
- Service de microbiologie, Assistance Publique–Hôpitaux de Paris. Centre–Université de Paris, Hôpital Necker Enfants Malades, Paris, France
| | - Daniel Euphrasie
- Université de Paris, Faculté de Médecine, Paris, France
- Institut Necker Enfants-Malades, Inserm U1151, CNRS UMR 8253, Paris, France
| | - Olivier Join-Lambert
- Université de Paris, Faculté de Médecine, Paris, France
- Institut Necker Enfants-Malades, Inserm U1151, CNRS UMR 8253, Paris, France
- Service de microbiologie, Assistance Publique–Hôpitaux de Paris. Centre–Université de Paris, Hôpital Necker Enfants Malades, Paris, France
| | - Mathilde Audry
- Université de Paris, Faculté de Médecine, Paris, France
- Institut Necker Enfants-Malades, Inserm U1151, CNRS UMR 8253, Paris, France
| | - Sophia Schonherr-Hellec
- Université de Paris, Faculté de Médecine, Paris, France
- Institut Necker Enfants-Malades, Inserm U1151, CNRS UMR 8253, Paris, France
| | - Taliah Schmitt
- Service de chirurgie reconstructrice et plastique, Groupe Hospitalier Paris Saint-Joseph, Paris, France
| | - Sandrine Bourdoulous
- Université de Paris, Faculté de Médecine, Paris, France
- Institut Cochin, Inserm U1016, CNRS UMR 8104, Paris, France
| | - Mathieu Coureuil
- Université de Paris, Faculté de Médecine, Paris, France
- Institut Necker Enfants-Malades, Inserm U1151, CNRS UMR 8253, Paris, France
| | - Xavier Nassif
- Université de Paris, Faculté de Médecine, Paris, France
- Institut Necker Enfants-Malades, Inserm U1151, CNRS UMR 8253, Paris, France
- Service de microbiologie, Assistance Publique–Hôpitaux de Paris. Centre–Université de Paris, Hôpital Necker Enfants Malades, Paris, France
| | - Mohamed El Behi
- Université de Paris, Faculté de Médecine, Paris, France
- Institut Necker Enfants-Malades, Inserm U1151, CNRS UMR 8253, Paris, France
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6
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Lim KYL, Mullally CA, Haese EC, Kibble EA, McCluskey NR, Mikucki EC, Thai VC, Stubbs KA, Sarkar-Tyson M, Kahler CM. Anti-Virulence Therapeutic Approaches for Neisseria gonorrhoeae. Antibiotics (Basel) 2021; 10:antibiotics10020103. [PMID: 33494538 PMCID: PMC7911339 DOI: 10.3390/antibiotics10020103] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/18/2021] [Accepted: 01/20/2021] [Indexed: 01/15/2023] Open
Abstract
While antimicrobial resistance (AMR) is seen in both Neisseria gonorrhoeae and Neisseria meningitidis, the former has become resistant to commonly available over-the-counter antibiotic treatments. It is imperative then to develop new therapies that combat current AMR isolates whilst also circumventing the pathways leading to the development of AMR. This review highlights the growing research interest in developing anti-virulence therapies (AVTs) which are directed towards inhibiting virulence factors to prevent infection. By targeting virulence factors that are not essential for gonococcal survival, it is hypothesized that this will impart a smaller selective pressure for the emergence of resistance in the pathogen and in the microbiome, thus avoiding AMR development to the anti-infective. This review summates the current basis of numerous anti-virulence strategies being explored for N. gonorrhoeae.
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Affiliation(s)
- Katherine Y. L. Lim
- Marshall Centre for Infectious Disease Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA 6009, Australia; (K.Y.L.L.); (C.A.M.); (E.C.H.); (E.A.K.); (N.R.M.); (E.C.M.); (V.C.T.); (M.S.-T.)
| | - Christopher A. Mullally
- Marshall Centre for Infectious Disease Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA 6009, Australia; (K.Y.L.L.); (C.A.M.); (E.C.H.); (E.A.K.); (N.R.M.); (E.C.M.); (V.C.T.); (M.S.-T.)
| | - Ethan C. Haese
- Marshall Centre for Infectious Disease Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA 6009, Australia; (K.Y.L.L.); (C.A.M.); (E.C.H.); (E.A.K.); (N.R.M.); (E.C.M.); (V.C.T.); (M.S.-T.)
| | - Emily A. Kibble
- Marshall Centre for Infectious Disease Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA 6009, Australia; (K.Y.L.L.); (C.A.M.); (E.C.H.); (E.A.K.); (N.R.M.); (E.C.M.); (V.C.T.); (M.S.-T.)
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia
| | - Nicolie R. McCluskey
- Marshall Centre for Infectious Disease Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA 6009, Australia; (K.Y.L.L.); (C.A.M.); (E.C.H.); (E.A.K.); (N.R.M.); (E.C.M.); (V.C.T.); (M.S.-T.)
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia
| | - Edward C. Mikucki
- Marshall Centre for Infectious Disease Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA 6009, Australia; (K.Y.L.L.); (C.A.M.); (E.C.H.); (E.A.K.); (N.R.M.); (E.C.M.); (V.C.T.); (M.S.-T.)
| | - Van C. Thai
- Marshall Centre for Infectious Disease Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA 6009, Australia; (K.Y.L.L.); (C.A.M.); (E.C.H.); (E.A.K.); (N.R.M.); (E.C.M.); (V.C.T.); (M.S.-T.)
| | - Keith A. Stubbs
- School of Molecular Sciences, University of Western Australia, Crawley, WA 6009, Australia;
| | - Mitali Sarkar-Tyson
- Marshall Centre for Infectious Disease Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA 6009, Australia; (K.Y.L.L.); (C.A.M.); (E.C.H.); (E.A.K.); (N.R.M.); (E.C.M.); (V.C.T.); (M.S.-T.)
| | - Charlene M. Kahler
- Marshall Centre for Infectious Disease Research and Training, School of Biomedical Sciences, University of Western Australia, Crawley, WA 6009, Australia; (K.Y.L.L.); (C.A.M.); (E.C.H.); (E.A.K.); (N.R.M.); (E.C.M.); (V.C.T.); (M.S.-T.)
- Correspondence:
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7
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Interactions and Signal Transduction Pathways Involved during Central Nervous System Entry by Neisseria meningitidis across the Blood-Brain Barriers. Int J Mol Sci 2020; 21:ijms21228788. [PMID: 33233688 PMCID: PMC7699760 DOI: 10.3390/ijms21228788] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 11/18/2020] [Indexed: 11/20/2022] Open
Abstract
The Gram-negative diplococcus Neisseria meningitidis, also called meningococcus, exclusively infects humans and can cause meningitis, a severe disease that can lead to the death of the afflicted individuals. To cause meningitis, the bacteria have to enter the central nervous system (CNS) by crossing one of the barriers protecting the CNS from entry by pathogens. These barriers are represented by the blood–brain barrier separating the blood from the brain parenchyma and the blood–cerebrospinal fluid (CSF) barriers at the choroid plexus and the meninges. During the course of meningococcal disease resulting in meningitis, the bacteria undergo several interactions with host cells, including the pharyngeal epithelium and the cells constituting the barriers between the blood and the CSF. These interactions are required to initiate signal transduction pathways that are involved during the crossing of the meningococci into the blood stream and CNS entry, as well as in the host cell response to infection. In this review we summarize the interactions and pathways involved in these processes, whose understanding could help to better understand the pathogenesis of meningococcal meningitis.
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8
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Azimi S, Wheldon LM, Oldfield NJ, Ala'Aldeen DAA, Wooldridge KG. A role for fibroblast growth factor receptor 1 in the pathogenesis of Neisseria meningitidis. Microb Pathog 2020; 149:104534. [PMID: 33045339 DOI: 10.1016/j.micpath.2020.104534] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 08/13/2020] [Accepted: 09/21/2020] [Indexed: 12/19/2022]
Abstract
Neisseria meningitidis (the meningococcus) remains an important cause of human disease, including meningitis and sepsis. Adaptation to the host environment includes many interactions with specific cell surface receptors, resulting in intracellular signalling and cytoskeletal rearrangements that contribute to pathogenesis. Here, we assessed the interactions between meningococci and Fibroblast Growth Factor Receptor 1-IIIc (FGFR1-IIIc): a receptor specific to endothelial cells of the microvasculature, including that of the blood-brain barrier. We show that the meningococcus recruits FGFR1-IIIc onto the surface of human blood microvascular endothelial cells (HBMECs). Furthermore, we demonstrate that expression of FGFR1-IIIc is required for optimal invasion of HBMECs by meningococci. We show that the ability of N. meningitidis to interact with the ligand-binding domain of FGFR1-IIIc is shared with the other pathogenic Neisseria species, N. gonorrhoeae, but not with commensal bacteria including non-pathogenic Neisseria species.
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Affiliation(s)
- Sheyda Azimi
- Molecular Bacteriology and Immunology Group, School of Life Sciences, University of Nottingham, UK
| | - Lee M Wheldon
- Molecular Bacteriology and Immunology Group, School of Life Sciences, University of Nottingham, UK
| | - Neil J Oldfield
- Molecular Bacteriology and Immunology Group, School of Life Sciences, University of Nottingham, UK
| | - Dlawer A A Ala'Aldeen
- Molecular Bacteriology and Immunology Group, School of Life Sciences, University of Nottingham, UK
| | - Karl G Wooldridge
- Molecular Bacteriology and Immunology Group, School of Life Sciences, University of Nottingham, UK.
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9
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Coureuil M, Jamet A, Bille E, Lécuyer H, Bourdoulous S, Nassif X. Molecular interactions between Neisseria meningitidis and its human host. Cell Microbiol 2019; 21:e13063. [PMID: 31167044 PMCID: PMC6899865 DOI: 10.1111/cmi.13063] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 05/21/2019] [Accepted: 05/30/2019] [Indexed: 02/06/2023]
Abstract
Neisseria meningitidis is a Gram‐negative bacterium that asymptomatically colonises the nasopharynx of humans. For an unknown reason, N. meningitidis can cross the nasopharyngeal barrier and invade the bloodstream where it becomes one of the most harmful extracellular bacterial pathogen. This infectious cycle involves the colonisation of two different environments. (a) In the nasopharynx, N. meningitidis grow on the top of mucus‐producing epithelial cells surrounded by a complex microbiota. To survive and grow in this challenging environment, the meningococcus expresses specific virulence factors such as polymorphic toxins and MDAΦ. (b) Meningococci have the ability to survive in the extra cellular fluids including blood and cerebrospinal fluid. The interaction of N. meningitidis with human endothelial cells leads to the formation of typical microcolonies that extend overtime and promote vascular injury, disseminated intravascular coagulation, and acute inflammation. In this review, we will focus on the interplay between N. meningitidis and these two different niches at the cellular and molecular level and discuss the use of inhibitors of piliation as a potent therapeutic approach.
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Affiliation(s)
- Mathieu Coureuil
- Inserm, Institut Necker Enfants Malades, U1151, Paris, France.,Université de Paris, UMR_S 1151, Paris, France.,CNRS, UMR 8253, Paris, France
| | - Anne Jamet
- Inserm, Institut Necker Enfants Malades, U1151, Paris, France.,Université de Paris, UMR_S 1151, Paris, France.,CNRS, UMR 8253, Paris, France.,Assistance Publique - Hôpitaux de Paris, Hôpital Necker Enfants Malades, Paris, France
| | - Emmanuelle Bille
- Inserm, Institut Necker Enfants Malades, U1151, Paris, France.,Université de Paris, UMR_S 1151, Paris, France.,CNRS, UMR 8253, Paris, France.,Assistance Publique - Hôpitaux de Paris, Hôpital Necker Enfants Malades, Paris, France
| | - Hervé Lécuyer
- Inserm, Institut Necker Enfants Malades, U1151, Paris, France.,Université de Paris, UMR_S 1151, Paris, France.,CNRS, UMR 8253, Paris, France.,Assistance Publique - Hôpitaux de Paris, Hôpital Necker Enfants Malades, Paris, France
| | - Sandrine Bourdoulous
- Université de Paris, UMR_S 1151, Paris, France.,Inserm, U1016, Institut Cochin, Paris, France.,CNRS, UMR8104, Paris, France
| | - Xavier Nassif
- Inserm, Institut Necker Enfants Malades, U1151, Paris, France.,Université de Paris, UMR_S 1151, Paris, France.,CNRS, UMR 8253, Paris, France.,Assistance Publique - Hôpitaux de Paris, Hôpital Necker Enfants Malades, Paris, France
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10
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Lenz JD, Dillard JP. Pathogenesis of Neisseria gonorrhoeae and the Host Defense in Ascending Infections of Human Fallopian Tube. Front Immunol 2018; 9:2710. [PMID: 30524442 PMCID: PMC6258741 DOI: 10.3389/fimmu.2018.02710] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 11/02/2018] [Indexed: 12/28/2022] Open
Abstract
Neisseria gonorrhoeae is an obligate human pathogen that causes mucosal surface infections of male and female reproductive tracts, pharynx, rectum, and conjunctiva. Asymptomatic or unnoticed infections in the lower reproductive tract of women can lead to serious, long-term consequences if these infections ascend into the fallopian tube. The damage caused by gonococcal infection and the subsequent inflammatory response produce the condition known as pelvic inflammatory disease (PID). Infection can lead to tubal scarring, occlusion of the oviduct, and loss of critical ciliated cells. Consequences of the damage sustained on the fallopian tube epithelium include increased risk of ectopic pregnancy and tubal-factor infertility. Additionally, the resolution of infection can produce new adhesions between internal tissues, which can tear and reform, producing chronic pelvic pain. As a bacterium adapted to life in a human host, the gonococcus presents a challenge to the development of model systems for probing host-microbe interactions. Advances in small-animal models have yielded previously unattainable data on systemic immune responses, but the specificity of N. gonorrhoeae for many known (and unknown) host targets remains a constant hurdle. Infections of human volunteers are possible, though they present ethical and logistical challenges, and are necessarily limited to males due to the risk of severe complications in women. It is routine, however, that normal, healthy fallopian tubes are removed in the course of different gynecological surgeries (namely hysterectomy), making the very tissue most consequentially damaged during ascending gonococcal infection available for laboratory research. The study of fallopian tube organ cultures has allowed the opportunity to observe gonococcal biology and immune responses in a complex, multi-layered tissue from a natural host. Forty-five years since the first published example of human fallopian tube being infected ex vivo with N. gonorrhoeae, we review what modeling infections in human tissue explants has taught us about the gonococcus, what we have learned about the defenses mounted by the human host in the upper female reproductive tract, what other fields have taught us about ciliated and non-ciliated cell development, and ultimately offer suggestions regarding the next generation of model systems to help expand our ability to study gonococcal pathogenesis.
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Affiliation(s)
- Jonathan D Lenz
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, United States
| | - Joseph P Dillard
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, United States
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11
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Schubert-Unkmeir A. Molecular mechanisms involved in the interaction of Neisseria meningitidis with cells of the human blood-cerebrospinal fluid barrier. Pathog Dis 2017; 75:3061359. [PMID: 28334198 DOI: 10.1093/femspd/ftx023] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 03/02/2017] [Indexed: 11/15/2022] Open
Abstract
Neisseria meningitidis is one of the most common aetiological agents of bacterial meningitis, affecting predominantly children and young adults. The interaction of N. meningitidis with human endothelial cells lining blood vessels of the blood-cerebrospinal fluid barrier (B-CSFB) is critical for meningitis development. In recent decades, there has been a significant increase in understanding of the molecular mechanisms involved in the interaction of N. meningitidis with brain vascular cells. In this review, we will describe how N. meningitidis adheres to the brain vasculature, may enter inside these cells, hijack receptor signalling pathways and alter host-cell responses in order to traverse the B-CSFB.
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12
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Weyand NJ. Neisseria models of infection and persistence in the upper respiratory tract. Pathog Dis 2017; 75:3078547. [DOI: 10.1093/femspd/ftx031] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 03/15/2017] [Indexed: 12/15/2022] Open
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13
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Arenas J, Tommassen J. Meningococcal Biofilm Formation: Let's Stick Together. Trends Microbiol 2017; 25:113-124. [DOI: 10.1016/j.tim.2016.09.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 09/13/2016] [Accepted: 09/16/2016] [Indexed: 11/26/2022]
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14
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Wang X, Zhang D, Sjölinder M, Wan Y, Sjölinder H. CD46 accelerates macrophage-mediated host susceptibility to meningococcal sepsis in a murine model. Eur J Immunol 2016; 47:119-130. [DOI: 10.1002/eji.201646397] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 09/04/2016] [Accepted: 10/26/2016] [Indexed: 12/18/2022]
Affiliation(s)
- Xiao Wang
- Department of Molecular Biosciences, the Wenner-Gren Institute; Stockholm University; Stockholm Sweden
| | - Ding Zhang
- College of Animal Science and Veterinary Medicine; Shanxi Agricultural University; Taigu China
| | - Mikael Sjölinder
- Department of Molecular Biosciences, the Wenner-Gren Institute; Stockholm University; Stockholm Sweden
| | - Yi Wan
- Department of Molecular Biosciences, the Wenner-Gren Institute; Stockholm University; Stockholm Sweden
| | - Hong Sjölinder
- Department of Molecular Biosciences, the Wenner-Gren Institute; Stockholm University; Stockholm Sweden
- Cancer Center; Mälar Hospital; Eskilstuna Sweden
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15
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Simonis A, Schubert-Unkmeir A. Interactions of meningococcal virulence factors with endothelial cells at the human blood-cerebrospinal fluid barrier and their role in pathogenicity. FEBS Lett 2016; 590:3854-3867. [PMID: 27498906 DOI: 10.1002/1873-3468.12344] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 07/08/2016] [Accepted: 07/31/2016] [Indexed: 01/06/2023]
Abstract
The Gram-negative extracellular bacterium Neisseria meningitidis is one of the most common aetiological agents of bacterial meningitis affecting predominantly young children worldwide. This bacterium is normally a quiescent coloniser of the upper respiratory tract, but in some individuals it enters the blood stream and causes invasive diseases, such as septicaemia and meningitis. Interactions of N. meningitidis with human endothelial cells are crucially involved in pathogencitiy, and great efforts have been made to understand these molecular interactions. The aim of this review article is to provide an overview of the interactions of meningococcal virulence factors with host endothelial cells at the blood-cerebrospinal fluid barrier.
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Affiliation(s)
- Alexander Simonis
- Division of Hematology, University Hospital Zurich, Switzerland.,Institute of Hygiene and Microbiology, University of Wuerzburg, Germany
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16
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Gasparini R, Panatto D, Bragazzi NL, Lai PL, Bechini A, Levi M, Durando P, Amicizia D. How the Knowledge of Interactions between Meningococcus and the Human Immune System Has Been Used to Prepare Effective Neisseria meningitidis Vaccines. J Immunol Res 2015; 2015:189153. [PMID: 26351643 PMCID: PMC4553322 DOI: 10.1155/2015/189153] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 06/09/2015] [Indexed: 01/17/2023] Open
Abstract
In the last decades, tremendous advancement in dissecting the mechanisms of pathogenicity of Neisseria meningitidis at a molecular level has been achieved, exploiting converging approaches of different disciplines, ranging from pathology to microbiology, immunology, and omics sciences (such as genomics and proteomics). Here, we review the molecular biology of the infectious agent and, in particular, its interactions with the immune system, focusing on both the innate and the adaptive responses. Meningococci exploit different mechanisms and complex machineries in order to subvert the immune system and to avoid being killed. Capsular polysaccharide and lipooligosaccharide glycan composition, in particular, play a major role in circumventing immune response. The understanding of these mechanisms has opened new horizons in the field of vaccinology. Nowadays different licensed meningococcal vaccines are available and used: conjugate meningococcal C vaccines, tetravalent conjugate vaccines, an affordable conjugate vaccine against the N. menigitidis serogroup A, and universal vaccines based on multiple antigens each one with a different and peculiar function against meningococcal group B strains.
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Affiliation(s)
- R. Gasparini
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
| | - D. Panatto
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
| | - N. L. Bragazzi
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
| | - P. L. Lai
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
| | - A. Bechini
- Department of Health Sciences, University of Florence, Viale G.B. Morgagni 48, 50134 Florence, Italy
| | - M. Levi
- Department of Health Sciences, University of Florence, Viale G.B. Morgagni 48, 50134 Florence, Italy
| | - P. Durando
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
| | - D. Amicizia
- Department of Health Sciences, University of Genoa, Via Pastore 1, 16132 Genoa, Italy
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17
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Invasive meningococcal disease: a disease of the endothelial cells. Trends Mol Med 2014; 20:571-8. [PMID: 25178566 DOI: 10.1016/j.molmed.2014.08.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 08/06/2014] [Accepted: 08/07/2014] [Indexed: 02/04/2023]
Abstract
Neisseria meningitidis is an extracellular pathogen, which, once in the bloodstream, has the ability to form microcolonies on the apical surface of endothelia. Pathogen interaction with microvessels is mediated by bacterial type IV pili and two receptors on endothelial cells: CD147 and the β2-adrenoceptor. CD147 facilitates the adhesion of diplococci to the endothelium, whereas the β2-adrenoceptor facilitates cell signaling, and crossing of the blood-brain barrier. In this review, we discuss how meningococcal interaction with endothelial cells is responsible for the specific clinical features of invasive meningococcal infection such as meningitis, and a peripheral thrombotic/vascular leakage syndrome possibly leading to purpura fulminans.
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18
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Melican K, Aubey F, Duménil G. Humanized mouse model to study bacterial infections targeting the microvasculature. J Vis Exp 2014. [PMID: 24747976 PMCID: PMC4161007 DOI: 10.3791/51134] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Neisseria meningitidis causes a severe, frequently fatal sepsis when it enters the human blood stream. Infection leads to extensive damage of the blood vessels resulting in vascular leak, the development of purpuric rashes and eventual tissue necrosis. Studying the pathogenesis of this infection was previously limited by the human specificity of the bacteria, which makes in vivo models difficult. In this protocol, we describe a humanized model for this infection in which human skin, containing dermal microvessels, is grafted onto immunocompromised mice. These vessels anastomose with the mouse circulation while maintaining their human characteristics. Once introduced into this model, N. meningitidis adhere exclusively to the human vessels, resulting in extensive vascular damage, inflammation and in some cases the development of purpuric rash. This protocol describes the grafting, infection and evaluation steps of this model in the context of N. meningitidis infection. The technique may be applied to numerous human specific pathogens that infect the blood stream.
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Affiliation(s)
- Keira Melican
- INSERM U970, Paris Cardiovascular Research Centre; Faculté de Médecine Paris Descartes, Université Paris Descartes
| | - Flore Aubey
- INSERM U970, Paris Cardiovascular Research Centre; Faculté de Médecine Paris Descartes, Université Paris Descartes
| | - Guillaume Duménil
- INSERM U970, Paris Cardiovascular Research Centre; Faculté de Médecine Paris Descartes, Université Paris Descartes;
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19
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Abstract
Type IV pili (T4P) are multifunctional protein fibers produced on the surfaces of a wide variety of bacteria and archaea. The major subunit of T4P is the type IV pilin, and structurally related proteins are found as components of the type II secretion (T2S) system, where they are called pseudopilins; of DNA uptake/competence systems in both Gram-negative and Gram-positive species; and of flagella, pili, and sugar-binding systems in the archaea. This broad distribution of a single protein family implies both a common evolutionary origin and a highly adaptable functional plan. The type IV pilin is a remarkably versatile architectural module that has been adopted widely for a variety of functions, including motility, attachment to chemically diverse surfaces, electrical conductance, acquisition of DNA, and secretion of a broad range of structurally distinct protein substrates. In this review, we consider recent advances in this research area, from structural revelations to insights into diversity, posttranslational modifications, regulation, and function.
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20
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Rendón MA, Hockenberry AM, McManus SA, So M. Sigma factor RpoN (σ54) regulates pilE transcription in commensal Neisseria elongata. Mol Microbiol 2013; 90:103-13. [PMID: 23899162 PMCID: PMC4474139 DOI: 10.1111/mmi.12350] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/28/2013] [Indexed: 01/29/2023]
Abstract
Human-adapted Neisseria includes two pathogens, Neisseria gonorrhoeae and Neisseria meningitidis, and at least 13 species of commensals that colonize many of the same niches as the pathogens. The Type IV pilus plays an important role in the biology of pathogenic Neisseria. In these species, Sigma factor RpoD (σ(70)), Integration Host Factor, and repressors RegF and CrgA regulate transcription of pilE, the gene encoding the pilus structural subunit. The Type IV pilus is also a strictly conserved trait in commensal Neisseria. We present evidence that a different mechanism regulates pilE transcription in commensals. Using Neisseria elongata as a model, we show that Sigma factor RpoN (σ(54)), Integration Host Factor, and an activator we name Npa regulate pilE transcription. Taken in context with previous reports, our findings indicate pilE regulation switched from an RpoN- to an RpoD-dependent mechanism as pathogenic Neisseria diverged from commensals during evolution. Our findings have implications for the timing of Tfp expression and Tfp-mediated host cell interactions in these two groups of bacteria.
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Affiliation(s)
- María A. Rendón
- The BIO5 Institute, University of Arizona, Tucson, AZ 85721, USA
- Department of Immunobiology, University of Arizona, Tucson, AZ 85721, USA
| | - Alyson M. Hockenberry
- The BIO5 Institute, University of Arizona, Tucson, AZ 85721, USA
- Department of Immunobiology, University of Arizona, Tucson, AZ 85721, USA
| | - Steven A. McManus
- Undergraduate Biology Research Program, University of Arizona, Tucson, AZ 85721, USA
| | - Magdalene So
- The BIO5 Institute, University of Arizona, Tucson, AZ 85721, USA
- Department of Immunobiology, University of Arizona, Tucson, AZ 85721, USA
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21
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Mutation of the conserved calcium-binding motif in Neisseria gonorrhoeae PilC1 impacts adhesion but not piliation. Infect Immun 2013; 81:4280-9. [PMID: 24002068 DOI: 10.1128/iai.00493-13] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Neisseria gonorrhoeae PilC1 is a member of the PilC family of type IV pilus-associated adhesins found in Neisseria species and other type IV pilus-producing genera. Previously, a calcium-binding domain was described in the C-terminal domains of PilY1 of Pseudomonas aeruginosa and in PilC1 and PilC2 of Kingella kingae. Genetic analysis of N. gonorrhoeae revealed a similar calcium-binding motif in PilC1. To evaluate the potential significance of this calcium-binding region in N. gonorrhoeae, we produced recombinant full-length PilC1 and a PilC1 C-terminal domain fragment. We show that, while alterations of the calcium-binding motif disrupted the ability of PilC1 to bind calcium, they did not grossly affect the secondary structure of the protein. Furthermore, we demonstrate that both full-length wild-type PilC1 and full-length calcium-binding-deficient PilC1 inhibited gonococcal adherence to cultured human cervical epithelial cells, unlike the truncated PilC1 C-terminal domain. Similar to PilC1 in K. kingae, but in contrast to the calcium-binding mutant of P. aeruginosa PilY1, an equivalent mutation in N. gonorrhoeae PilC1 produced normal amounts of pili. However, the N. gonorrhoeae PilC1 calcium-binding mutant still had partial defects in gonococcal adhesion to ME180 cells and genetic transformation, which are both essential virulence factors in this human pathogen. Thus, we conclude that calcium binding to PilC1 plays a critical role in pilus function in N. gonorrhoeae.
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22
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Hung MC, Christodoulides M. The biology of Neisseria adhesins. BIOLOGY 2013; 2:1054-109. [PMID: 24833056 PMCID: PMC3960869 DOI: 10.3390/biology2031054] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 07/01/2013] [Accepted: 07/03/2013] [Indexed: 01/15/2023]
Abstract
Members of the genus Neisseria include pathogens causing important human diseases such as meningitis, septicaemia, gonorrhoea and pelvic inflammatory disease syndrome. Neisseriae are found on the exposed epithelia of the upper respiratory tract and the urogenital tract. Colonisation of these exposed epithelia is dependent on a repertoire of diverse bacterial molecules, extending not only from the surface of the bacteria but also found within the outer membrane. During invasive disease, pathogenic Neisseriae also interact with immune effector cells, vascular endothelia and the meninges. Neisseria adhesion involves the interplay of these multiple surface factors and in this review we discuss the structure and function of these important molecules and the nature of the host cell receptors and mechanisms involved in their recognition. We also describe the current status for recently identified Neisseria adhesins. Understanding the biology of Neisseria adhesins has an impact not only on the development of new vaccines but also in revealing fundamental knowledge about human biology.
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Affiliation(s)
- Miao-Chiu Hung
- Neisseria Research, Molecular Microbiology, Clinical and Experimental Sciences, Sir Henry Wellcome Laboratories, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, SO16 6YD, UK.
| | - Myron Christodoulides
- Neisseria Research, Molecular Microbiology, Clinical and Experimental Sciences, Sir Henry Wellcome Laboratories, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, SO16 6YD, UK.
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23
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Coureuil M, Join-Lambert O, Lécuyer H, Bourdoulous S, Marullo S, Nassif X. Pathogenesis of meningococcemia. Cold Spring Harb Perspect Med 2013; 3:3/6/a012393. [PMID: 23732856 DOI: 10.1101/cshperspect.a012393] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Neisseria meningitidis is responsible for two major diseases: cerebrospinal meningitis and/or septicemia. The latter can lead to a purpura fulminans, an often-fatal condition owing to the associated septic shock. These two clinical aspects of the meningococcal infection are consequences of a tight interaction of meningococci with host endothelial cells. This interaction, mediated by the type IV pili, is responsible for the formation of microcolonies on the apical surface of the cells. This interaction is followed by the activation of signaling pathways in the host cells leading to the formation of a microbiological synapse. A low level of bacteremia is likely to favor the colonization of brain vessels, leading to bacterial meningitis, whereas the colonization of a large number of vessels by a high number of bacteria is responsible for one of the most severe forms of septic shock observed.
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24
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Dual pili post-translational modifications synergize to mediate meningococcal adherence to platelet activating factor receptor on human airway cells. PLoS Pathog 2013; 9:e1003377. [PMID: 23696740 PMCID: PMC3656113 DOI: 10.1371/journal.ppat.1003377] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2012] [Accepted: 04/05/2013] [Indexed: 12/02/2022] Open
Abstract
Pili of pathogenic Neisseria are major virulence factors associated with adhesion, twitching motility, auto-aggregation, and DNA transformation. Pili of N. meningitidis are subject to several different post-translational modifications. Among these pilin modifications, the presence of phosphorylcholine (ChoP) and a glycan on the pilin protein are phase-variable (subject to high frequency, reversible on/off switching of expression). In this study we report the location of two ChoP modifications on the C-terminus of N. meningitidis pilin. We show that the surface accessibility of ChoP on pili is affected by phase variable changes to the structure of the pilin-linked glycan. We identify for the first time that the platelet activating factor receptor (PAFr) is a key, early event receptor for meningococcal adherence to human bronchial epithelial cells and tissue, and that synergy between the pilin-linked glycan and ChoP post-translational modifications is required for pili to optimally engage PAFr to mediate adherence to human airway cells. Neisseria meningitidis is an important human pathogen that can cause rapidly progressing, life threatening meningitis and sepsis in humans. There is no fully protective vaccine against this pathogen in current use and the key processes that dictate the transition from harmless carriage of the bacterium in the airway (the case for the vast majority of colonised hosts) to invasive disease are largely undefined. A key missing link in this organism's interaction with the human host is the identity of the receptor that is the first point of contact for the organism within the airway. In this study, we report that the receptor for this important human pathogen on airway epithelial cells is the platelet activating factor receptor (PAFr), an immunomodulatory molecule shown by others to play a role in promoting bacterial sepsis. We also show that two post-translational modifications, glycosylation and phosphorylcholine, are subject to phase-variation (high frequency, reversible switching of gene expression). They are closely associated on adjacent pilin subunits, and synergy between both are required for the efficient engagement with the PAFr. These data define a new role for these post-translational modifications in meningococcal adherence and also provide an insight into the selective pressures that underlie their phase variable expression.
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25
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26
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Miller F, Lécuyer H, Join-Lambert O, Bourdoulous S, Marullo S, Nassif X, Coureuil M. Neisseria meningitidis colonization of the brain endothelium and cerebrospinal fluid invasion. Cell Microbiol 2012. [PMID: 23189983 DOI: 10.1111/cmi.12082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The brain and meningeal spaces are protected from bacterial invasion by the blood-brain barrier, formed by specialized endothelial cells and tight intercellular junctional complexes. However, once in the bloodstream, Neisseria meningitidis crosses this barrier in about 60% of the cases. This highlights the particular efficacy with which N. meningitidis targets the brain vascular cell wall. The first step of central nervous system invasion is the direct interaction between bacteria and endothelial cells. This step is mediated by the type IV pili, which induce a remodelling of the endothelial monolayer, leading to the opening of the intercellular space. In this review, strategies used by the bacteria to survive in the bloodstream, to colonize the brain vasculature and to cross the blood-brain barrier will be discussed.
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Affiliation(s)
- Florence Miller
- INSERM, unité U1002, Paris, France; Université Paris Descartes, Sorbonne Paris Cité, Faculté de médecine, Paris, France
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27
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Thanassi DG, Bliska JB, Christie PJ. Surface organelles assembled by secretion systems of Gram-negative bacteria: diversity in structure and function. FEMS Microbiol Rev 2012; 36:1046-82. [PMID: 22545799 PMCID: PMC3421059 DOI: 10.1111/j.1574-6976.2012.00342.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2011] [Revised: 03/08/2012] [Accepted: 04/13/2012] [Indexed: 11/29/2022] Open
Abstract
Gram-negative bacteria express a wide variety of organelles on their cell surface. These surface structures may be the end products of secretion systems, such as the hair-like fibers assembled by the chaperone/usher (CU) and type IV pilus pathways, which generally function in adhesion to surfaces and bacterial-bacterial and bacterial-host interactions. Alternatively, the surface organelles may be integral components of the secretion machinery itself, such as the needle complex and pilus extensions formed by the type III and type IV secretion systems, which function in the delivery of bacterial effectors inside host cells. Bacterial surface structures perform functions critical for pathogenesis and have evolved to withstand forces exerted by the external environment and cope with defenses mounted by the host immune system. Given their essential roles in pathogenesis and exposed nature, bacterial surface structures also make attractive targets for therapeutic intervention. This review will describe the structure and function of surface organelles assembled by four different Gram-negative bacterial secretion systems: the CU pathway, the type IV pilus pathway, and the type III and type IV secretion systems.
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Affiliation(s)
- David G Thanassi
- Center for Infectious Diseases, Stony Brook University, Stony Brook, NY 11794-5120, USA.
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28
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Identification of Bartonella Trw host-specific receptor on erythrocytes. PLoS One 2012; 7:e41447. [PMID: 22848496 PMCID: PMC3406051 DOI: 10.1371/journal.pone.0041447] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Accepted: 06/27/2012] [Indexed: 01/22/2023] Open
Abstract
Each Bartonella species appears to be highly adapted to one or a limited number of reservoir hosts, in which it establishes long-lasting intraerythrocytic bacteremia as the hallmark of infection. Recently, we identified Trw as the bacterial system involved in recognition of erythrocytes according to their animal origin. The T4SS Trw is characterized by a multiprotein complex that spans the inner and outer bacterial membranes, and possesses a hypothetical pilus structure. TrwJ, I, H and trwL are present in variable copy numbers in different species and the multiple copies of trwL and trwJ in the Bartonella trw locus are considered to encode variant forms of surface-exposed pilus components. We therefore aimed to identify which of the candidate Trw pilus components were located on the bacterial surface and involved in adhesion to erythrocytes, together with their erythrocytic receptor. Using different technologies (electron microscopy, phage display, invasion inhibition assay, far western blot), we found that only TrwJ1 and TrwJ2 were expressed and localized at the cell surface of B. birtlesii and had the ability to bind to mouse erythrocytes, and that their receptor was band3, one of the major outer-membrane glycoproteins of erythrocytes, (anion exchanger). According to these results, we propose that the interaction between TrwJ1, TrwJ2 and band 3 leads to the critical host-specific adherence of Bartonella to its host cells, erythrocytes.
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29
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Chen Y, Sjölinder M, Wang X, Altenbacher G, Hagner M, Berglund P, Gao Y, Lu T, Jonsson AB, Sjölinder H. Thyroid hormone enhances nitric oxide-mediated bacterial clearance and promotes survival after meningococcal infection. PLoS One 2012; 7:e41445. [PMID: 22844479 PMCID: PMC3402396 DOI: 10.1371/journal.pone.0041445] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 06/21/2012] [Indexed: 12/04/2022] Open
Abstract
Euthyroid sick syndrome characterized by reduced levels of thyroid hormones (THs) is observed in patients with meningococcal shock. It has been found that the level of THs reflects disease severity and is predictive for mortality. The present study was conducted to investigate the impact of THs on host defense during meningococcal infection. We found that supplementation of thyroxine to mice infected with Neisseria meningitidis enhanced bacterial clearance, attenuated the inflammatory responses and promoted survival. In vitro studies with macrophages revealed that THs enhanced bacteria-cell interaction and intracellular killing of meningococci by stimulating inducible nitric oxide synthase (iNos)-mediated NO production. TH treatment did not activate expression of TH receptors in macrophages. Instead, the observed TH-directed actions were mediated through nongenomic pathways involving the protein kinases PI3K and ERK1/2 and initiated at the membrane receptor integrin αvβ3. Inhibition of nongenomic TH signaling prevented iNos induction, NO production and subsequent intracellular bacterial killing by macrophages. These data demonstrate a beneficial role of THs in macrophage-mediated N. meningitidis clearance. TH replacement might be a novel option to control meningococcal septicemia.
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Affiliation(s)
- Yao Chen
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Mikael Sjölinder
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Xiao Wang
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Georg Altenbacher
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Matthias Hagner
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Pernilla Berglund
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Yumin Gao
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Ting Lu
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Ann-Beth Jonsson
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Hong Sjölinder
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
- * E-mail:
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30
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The meningococcal minor pilin PilX is responsible for type IV pilus conformational changes associated with signaling to endothelial cells. Infect Immun 2012; 80:3297-306. [PMID: 22778100 DOI: 10.1128/iai.00369-12] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Neisseria meningitidis crosses the blood-brain barrier (BBB) following the activation of the β2-adrenergic receptor by the type IV pili (TFP). Two components of the type IV pili recruit the β2-adrenergic receptor, the major pilin PilE and the minor pilin PilV. Here, we report that a strain deleted of PilX, one of the three minor pilins, is defective in endothelial cell signaling. The signaling role of PilX was abolished when pili were not retractable. Purified PilX was unable to recruit the β2-adrenergic receptor, thus suggesting that PilX was playing an indirect role in endothelial cell signaling. Considering the recent finding that type IV pili can transition into a new conformation (N. Biais, D. L. Higashi, J. Brujic, M. So, and M. P. Sheetz, Proc. Natl. Acad. Sci. U. S. A. 107:11358-11363, 2010), we hypothesized that PilX was responsible for a structural modification of the fiber and allowed hidden epitopes to be exposed. To confirm this hypothesis, we showed that a monoclonal antibody which recognizes a linear epitope of PilE bound fibers only when bacteria adhered to endothelial cells. On the other hand, this effect was not observed in PilX-deleted pili. A deletion of a region of PilX exposed on the surface of the fiber had phenotypical consequences identical to those of a PilX deletion. These data support a model in which surface-exposed motifs of PilX use forces generated by pilus retraction to promote conformational changes required for TFP-mediated signaling.
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31
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Coureuil M, Join-Lambert O, Lécuyer H, Bourdoulous S, Marullo S, Nassif X. Mechanism of meningeal invasion by Neisseria meningitidis. Virulence 2012; 3:164-72. [PMID: 22366962 PMCID: PMC3396695 DOI: 10.4161/viru.18639] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The blood-cerebrospinal fluid barrier physiologically protects the meningeal spaces from blood-borne bacterial pathogens, due to the existence of specialized junctional interendothelial complexes. Few bacterial pathogens are able to reach the subarachnoidal space and among those, Neisseria meningitidis is the one that achieves this task the most constantly when present in the bloodstream. Meningeal invasion is a consequence of a tight interaction of meningococci with brain endothelial cells. This interaction, mediated by the type IV pili, is responsible for the formation of microcolonies on the apical surface of the cells. This interaction is followed by the activation of signaling pathways in the host cells leading to the formation of endothelial docking structures resembling those elicited by the interaction of leukocytes with endothelial cells during extravasation. The consequence of these bacterial-induced signaling events is the recruitment of intercellular junction components in the docking structure and the subsequent opening of the intercellular junctions.
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Neisseria gonorrhoeae pilus attenuates cytokine response of human fallopian tube explants. J Biomed Biotechnol 2012; 2012:491298. [PMID: 22318778 PMCID: PMC3270410 DOI: 10.1155/2012/491298] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Revised: 10/10/2011] [Accepted: 10/16/2011] [Indexed: 11/17/2022] Open
Abstract
Background. A role for pilus during attachment of Neisseria gonorrhoeae to epithelia of the female reproductive tract is currently assumed. However, Pil− gonococci have been observed during infection of the reproductive tract, which prompted us to examine the effect of pili on the dynamics of infection and the inflammatory responses of mucosal explants of the human Fallopian tube. Methods. Mucosal explants were infected in vitro with Opa negative Pil− and Pil+N. gonorrhoeae strains. Results. Piliation enhanced gonococcal adherence to the epithelium within 3 h of infection (P < 0.05) but thereafter did not offer advantage to gonococci to colonize the epithelial cell surface (P > 0.05). No differences were found between the strains in numbers of gonococci inside epithelial cells. Pil− bacteria induced higher levels (P < 0.05) of IL-1β, TNF-α, GM-CSF, MCP-1, and MIP-1β than Pil+ bacteria. There were no differences between both strains in LOS pattern, and Pil expression did not change after coincubation with mucosal strips. Conclusions. Results show that gonococcal invasion of the human Fallopian tube can occur independently of pilus or Opa expression, and suggest that pilus, by inhibition of several key elements of the initial inflammatory response, facilitates sustained infection of this organ.
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Abstract
Meningococcal mechanisms of adhesion are complex, involving multiple adhesins and their respective target receptors on host cells. Three major surface structures--pili, Opa, and Opc--have been known for some time to mediate meningococcal adhesion to target human cells. More recently, several other relatively minor adhesins have also come to light. The literature on bacterial adhesion mechanisms provides numerous examples of various adhesins acting cooperatively in an apparently hierarchical and sequential manner; in other instances, adhesins may act in concert leading to high avidity interactions, often a prelude to cellular invasion and tissue penetration. Such examples are also present in the case of meningococci, although our knowledge of adhesin cooperation and synergy is far from complete. Meningococcal mechanisms used to target the host, which are often specific for the host or a tissue within the host, include both lectin-like interactions and protein-protein interactions; the latter tend to determine specificity in general. Understanding (a) what determines specificity (i.e. molecular features of adhesins and receptors), (b) encourages cellular penetration (i.e. adhesin pairs, which act in concert or synergistically to deliver effective signals for invasion and induce other cellular responses), (c) level of redundancy (more than one mechanisms of targeting host receptors), (d) host situations that encourage tissue penetration (inflammatory situations during which circulating cytokines upregulate target cell receptors, effectively encouraging greater adhesion/invasion), and (e) down-stream effects on host functions in general are all clearly important in our future strategies of controlling meningococcal pathogenesis.
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Johnson MDL, Garrett CK, Bond JE, Coggan KA, Wolfgang MC, Redinbo MR. Pseudomonas aeruginosa PilY1 binds integrin in an RGD- and calcium-dependent manner. PLoS One 2011; 6:e29629. [PMID: 22242136 PMCID: PMC3248442 DOI: 10.1371/journal.pone.0029629] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 12/02/2011] [Indexed: 11/18/2022] Open
Abstract
PilY1 is a type IV pilus (tfp)-associated protein from the opportunistic pathogen Pseudomonas aeruginosa that shares functional similarity with related proteins in infectious Neisseria and Kingella species. Previous data have shown that PilY1 acts as a calcium-dependent pilus biogenesis factor necessary for twitching motility with a specific calcium binding site located at amino acids 850–859 in the 1,163 residue protein. In addition to motility, PilY1 is also thought to play an important role in the adhesion of P. aeruginosa tfp to host epithelial cells. Here, we show that PilY1 contains an integrin binding arginine-glycine-aspartic acid (RGD) motif located at residues 619–621 in the PilY1 from the PAK strain of P. aeruginosa; this motif is conserved in the PilY1s from the other P. aeruginosa strains of known sequence. We demonstrate that purified PilY1 binds integrin in vitro in an RGD-dependent manner. Furthermore, we identify a second calcium binding site (amino acids 600–608) located ten residues upstream of the RGD. Eliminating calcium binding from this site using a D608A mutation abolished integrin binding; in contrast, a calcium binding mimic (D608K) preserved integrin binding. Finally, we show that the previously established PilY1 calcium binding site at 851–859 also impacts the protein's association with integrin. Taken together, these data indicate that PilY1 binds to integrin in an RGD- and calcium-dependent manner in vitro. As such, P. aeruginosa may employ these interactions to mediate host epithelial cell binding in vivo.
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Affiliation(s)
- Michael D. L. Johnson
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Christopher K. Garrett
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Jennifer E. Bond
- Division of Plastic and Reconstructive Surgery, Department of Surgery, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Kimberly A. Coggan
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Matthew C. Wolfgang
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Cystic Fibrosis/Pulmonary Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Matthew R. Redinbo
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
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Vascular colonization by Neisseria meningitidis. Curr Opin Microbiol 2011; 15:50-6. [PMID: 22185907 DOI: 10.1016/j.mib.2011.10.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 10/13/2011] [Accepted: 10/14/2011] [Indexed: 11/21/2022]
Abstract
Bacterial infection of human vasculature can lead to unregulated systemic activation of coagulation and innate immunity and rapidly becomes life threatening. Neisseria meningitidis is a vascular pathogen that causes fatal sepsis and meningitis. Post-mortem histological analysis of tissues from individuals infected with N. meningitidis show large bacterial aggregates in close association with the vascular wall of small vessels. The ability of this bacterium to colonize blood vessel endothelium is likely to impact its capacity to both multiply in the blood stream and reach the brain. This process will be referred to as vascular colonization. Recent work has described a number of early steps in N. meningitidis vascular colonization, from attachment to proliferation and dissemination, focusing on the bacterial-host interaction.
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Two strikingly different signaling pathways are induced by meningococcal type IV pili on endothelial and epithelial cells. Infect Immun 2011; 80:175-86. [PMID: 22064711 DOI: 10.1128/iai.05837-11] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Following adhesion on brain microvasculature, Neisseria meningitidis is able to cross the blood-brain barrier (BBB) by recruiting the polarity complex and the cell junction proteins, thus allowing the opening of the paracellular route. This feature is the consequence of the activation by the type IV pili of the β2-adrenergic receptor/β-arrestin signaling pathway. Here, we have extended this observation to primary peripheral endothelial cells, and we report that the interaction of N. meningitidis with the epithelium is strikingly different. The recruitment of the junctional components by N. meningitidis is indeed restricted to endothelial cell lines, and no alteration of the cell-cell junctions can be seen in epithelial monolayers following meningococcal type IV pilus-mediated colonization. Consistently, the β2-adrenergic receptor/β-arrestin pathway was not hijacked by bacteria adhering on epithelial cells. In addition, we showed that the consequences of the bacterial signaling on epithelial cells is different from that of endothelial cells, since N. meningitidis-induced signaling which protects the microcolonies from shear stress on endothelial cells is unable to do so on epithelial cells. Finally, we report that the minor pilin PilV, which has been shown to be essential for endothelial cell response, is not a required bacterial determinant to induce an epithelial cell response. These data demonstrate that even though pilus-mediated signaling induces an apparently similar cortical plaque, in epithelial and endothelial cell lineages, the signaling pathways are strikingly different in both models.
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Bencurova E, Mlynarcik P, Bhide M. An insight into the ligand-receptor interactions involved in the translocation of pathogens across blood-brain barrier. ACTA ACUST UNITED AC 2011; 63:297-318. [PMID: 22092557 DOI: 10.1111/j.1574-695x.2011.00867.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2011] [Revised: 08/09/2011] [Accepted: 09/02/2011] [Indexed: 01/01/2023]
Abstract
Traversal of pathogen across the blood-brain barrier (BBB) is an essential step for central nervous system (CNS) invasion. Pathogen traversal can occur paracellularly, transcellularly, and/or in infected phagocytes (Trojan horse mechanism). To trigger the translocation processes, mainly through paracellular and transcellular ways, interactions between protein molecules of pathogen and BBB are inevitable. Simply, it takes two to tango: both host receptors and pathogen ligands. Underlying molecular basis of BBB translocation of various pathogens has been revealed in the last decade, and a plethora of experimental data on protein-protein interactions has been created. This review compiles these data and should give insights into the ligand-receptor interactions that occur during BBB translocation. Further, it sheds light on cell signaling events triggered in response to ligand-receptor interaction. Understanding of the molecular principles of pathogen-host interactions that are involved in traversal of the BBB should contribute to develop new vaccine and drug strategies to prevent CNS infections.
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Affiliation(s)
- Elena Bencurova
- Laboratory of Biomedical Microbiology and Immunology, Department of Microbiology and Immunology, University of Veterinary Medicine and Pharmacy, Kosice, Slovakia
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Söderholm N, Vielfort K, Hultenby K, Aro H. Pathogenic Neisseria hitchhike on the uropod of human neutrophils. PLoS One 2011; 6:e24353. [PMID: 21949708 PMCID: PMC3174955 DOI: 10.1371/journal.pone.0024353] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2011] [Accepted: 08/05/2011] [Indexed: 11/18/2022] Open
Abstract
Polymorphonuclear neutrophils (PMNs) are important components of the human innate immune system and are rapidly recruited at the site of bacterial infection. Despite the effective phagocytic activity of PMNs, Neisseria gonorrhoeae infections are characterized by high survival within PMNs. We reveal a novel type IV pilus-mediated adherence of pathogenic Neisseria to the uropod (the rear) of polarized PMNs. The direct pilus-uropod interaction was visualized by scanning electron microscopy and total internal reflection fluorescence (TIRF) microscopy. We showed that N. meningitidis adhesion to the PMN uropod depended on both pilus-associated proteins PilC1 and PilC2, while N. gonorrhoeae adhesion did not. Bacterial adhesion elicited accumulation of the complement regulator CD46, but not I-domain-containing integrins, beneath the adherent bacterial microcolony. Electrographs and live-cell imaging of PMNs suggested that bacterial adherence to the uropod is followed by internalization into PMNs via the uropod. We also present data showing that pathogenic Neisseria can hitchhike on PMNs to hide from their phagocytic activity as well as to facilitate the spread of the pathogen through the epithelial cell layer.
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Affiliation(s)
- Niklas Söderholm
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Katarina Vielfort
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
| | - Kjell Hultenby
- Department of Laboratory Medicine, Karolinska Institute, Huddinge, Sweden
| | - Helena Aro
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden
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Trivedi K, Tang CM, Exley RM. Mechanisms of meningococcal colonisation. Trends Microbiol 2011; 19:456-63. [PMID: 21816616 DOI: 10.1016/j.tim.2011.06.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 06/16/2011] [Accepted: 06/28/2011] [Indexed: 01/05/2023]
Abstract
Despite advances against infectious diseases over the past century, Neisseria meningitidis remains a major causative agent of meningitis and septicaemia worldwide. Its adaptation for survival in the human nasopharynx makes the meningococcus a highly successful commensal bacterium. Recent progress has been made in understanding the mechanisms that enable neisserial colonisation, in terms of the role of type IV pili, the impact of other adhesins, biofilm formation, nutrient acquisition and resistance to host immune defences. Refinements in cell-based and in vivo models will lead to improved understanding of the colonisation process, and hopefully to more effective vaccines and therapeutic strategies.
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Affiliation(s)
- Kaushali Trivedi
- Centre for Molecular Microbiology and Infection, Faculty of Medicine, Flowers Building, Imperial College London, London SW7 2AZ, UK
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Kuwae A, Sjölinder H, Eriksson J, Eriksson S, Chen Y, Jonsson AB. NafA negatively controls Neisseria meningitidis piliation. PLoS One 2011; 6:e21749. [PMID: 21747953 PMCID: PMC3128610 DOI: 10.1371/journal.pone.0021749] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 06/06/2011] [Indexed: 12/02/2022] Open
Abstract
Bacterial auto-aggregation is a critical step during adhesion of N. meningitidis to host cells. The precise mechanisms and functions of bacterial auto-aggregation still remain to be fully elucidated. In this work, we characterize the role of a meningococcal hypothetical protein, NMB0995/NMC0982, and show that this protein, here denoted NafA, acts as an anti-aggregation factor. NafA was confirmed to be surface exposed and was found to be induced at a late stage of bacterial adherence to epithelial cells. A NafA deficient mutant was hyperpiliated and formed bundles of pili. Further, the mutant displayed increased adherence to epithelial cells when compared to the wild-type strain. In the absence of host cells, the NafA deficient mutant was more aggregative than the wild-type strain. The in vivo role of NafA in sepsis was studied in a murine model of meningococcal disease. Challenge with the NafA deficient mutant resulted in lower bacteremia levels and mortality when compared to the wild-type strain. The present study reveals that meningococcal NafA is an anti-aggregation factor with strong impact on the disease outcome. These data also suggest that appropriate bacterial auto-aggregation is controlled by both aggregation and anti-aggregation factors during Neisseria infection in vivo.
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Affiliation(s)
- Asaomi Kuwae
- Department of Genetics, Microbiology and Toxicology, Stockholm University, Stockholm, Sweden.
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41
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Edwards JL, Butler EK. The Pathobiology of Neisseria gonorrhoeae Lower Female Genital Tract Infection. Front Microbiol 2011; 2:102. [PMID: 21747805 PMCID: PMC3129011 DOI: 10.3389/fmicb.2011.00102] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 04/25/2011] [Indexed: 11/13/2022] Open
Abstract
Infection and disease associated with Neisseria gonorrhoeae, the gonococcus, continue to be a global health problem. Asymptomatic and subclinical gonococcal infections occur at a high frequency in females; thus, the true incidence of N. gonorrhoeae infections are presumed to be severely underestimated. Inherent to this asymptomatic/subclinical diseased state is the continued prevalence of this organism within the general population, as well as the medical, economic, and social burden equated with the observed chronic, disease sequelae. As infections of the lower female genital tract (i.e., the uterine cervix) commonly result in subclinical disease, it follows that the pathobiology of cervical gonorrhea would differ from that observed for other sites of infection. In this regard, the potential responses to infection that are generated by the female reproductive tract mucosa are unique in that they are governed, in part, by cyclic fluctuations in steroid hormone levels. The lower female genital tract has the further distinction of being able to functionally discriminate between resident commensal microbiota and transient pathogens. The expression of functionally active complement receptor 3 by the lower, but not the upper, female genital tract mucosa; together with data indicating that gonococcal adherence to and invasion of primary cervical epithelial cells and tissue are predominately aided by this surface-expressed host molecule; provide one explanation for asymptomatic/subclinical gonococcal cervicitis. However, co-evolution of the gonococcus with its sole human host has endowed this organism with variable survival strategies that not only aid these bacteria in successfully evasion of immune detection and function but also enhance cervical colonization and cellular invasion. To this end, we herein summarize current knowledge pertaining to the pathobiology of gonococcal infection of the human cervix.
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Affiliation(s)
- Jennifer L Edwards
- The Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, The Ohio State University Columbus, OH, USA
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42
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Jennings MP, Jen FEC, Roddam LF, Apicella MA, Edwards JL. Neisseria gonorrhoeae pilin glycan contributes to CR3 activation during challenge of primary cervical epithelial cells. Cell Microbiol 2011; 13:885-96. [PMID: 21371235 DOI: 10.1111/j.1462-5822.2011.01586.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Expression of type IV pili by Neisseria gonorrhoeae plays a critical role in mediating adherence to human epithelial cells. Gonococcal pilin is modified with an O-linked glycan, which may be present as a di- or monosaccharide because of phase variation of select pilin glycosylation genes. It is accepted that bacterial proteins may be glycosylated; less clear is how the protein glycan may mediate virulence. Using primary, human, cervical epithelial (i.e. pex) cells, we now provide evidence to indicate that the pilin glycan mediates productive cervical infection. In this regard, pilin glycan-deficient mutant gonococci exhibited an early hyper-adhesive phenotype but were attenuated in their ability to invade pex cells. Our data further indicate that the pilin glycan was required for gonococci to bind to the I-domain region of complement receptor 3, which is naturally expressed by pex cells. Comparative, quantitative, infection assays revealed that mutant gonococci lacking the pilin glycan did not bind to the I-domain when it is in a closed, low-affinity conformation and cannot induce an active conformation to complement receptor 3 during pex cell challenge. To our knowledge, these are the first data to directly demonstrate how a protein-associated bacterial glycan may contribute to pathogenesis.
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Affiliation(s)
- Michael P Jennings
- Institute for Glycomics, Griffith University, Gold Coast Campus, Australia
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Meningococcal internalization into human endothelial and epithelial cells is triggered by the influx of extracellular L-glutamate via GltT L-glutamate ABC transporter in Neisseria meningitidis. Infect Immun 2010; 79:380-92. [PMID: 20956569 DOI: 10.1128/iai.00497-10] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Meningococcal internalization into human cells is likely to be a consequence of meningococcal adhesion to human epithelial and endothelial cells. Here, we identified three transposon mutants of Neisseria meningitidis that were primarily defective in the internalization of human brain microvascular endothelial cells (HBMEC), with insertions occurring in the gltT (a sodium-independent L-glutamate transporter) gene or its neighboring gene, NMB1964 (unknown function). NMB1964 was tentatively named gltM in this study because of the presence of a mammalian cell entry (MCE)-related domain in the deduced amino acid sequences. The null ΔgltT-ΔgltM N. meningitidis mutant was also defective in the internalization into human umbilical vein endothelial cells and the human lung carcinoma epithelial cell line A549, and the defect was suppressed by transcomplementation of the mutants with gltT(+)-gltM(+) genes. The intracellular survival of the ΔgltT-ΔgltM mutant in HBMEC was not largely different from that of the wild-type strain under our experimental conditions. Introduction of a1-bp deletion and amber or ochre mutations in gltT-gltM genes resulted in the loss of efficient internalization into HBMEC. The defect in meningococcal internalization into HBMEC and L-glutamate uptake in the ΔgltT-ΔgltM mutant were suppressed only in strains expressing both GltT and GltM proteins. The efficiency of meningococcal invasion to HBMEC decreased under L-glutamate-depleted conditions. Furthermore, ezrin, a key membrane-cytoskeleton linker, accumulated beneath colonies of the gltT(+)-gltM(+) N. meningitidis strain but not of the ΔgltT-ΔgltM mutant. These findings suggest that l-glutamate influx via the GltT-GltM L-glutamate ABC transporter serves as a cue for N. meningitidis internalization into host cells.
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Boettcher JP, Kirchner M, Churin Y, Kaushansky A, Pompaiah M, Thorn H, Brinkmann V, MacBeath G, Meyer TF. Tyrosine-phosphorylated caveolin-1 blocks bacterial uptake by inducing Vav2-RhoA-mediated cytoskeletal rearrangements. PLoS Biol 2010; 8. [PMID: 20808760 PMCID: PMC2927421 DOI: 10.1371/journal.pbio.1000457] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Accepted: 07/07/2010] [Indexed: 12/11/2022] Open
Abstract
During the early stages of infection, Neisseria gonorrhoeae triggers a phosphotyrosine-dependent Cav1-Vav2-RhoA signaling cascade that promotes the pathogen's extracellular state. Certain bacterial adhesins appear to promote a pathogen's extracellular lifestyle rather than its entry into host cells. However, little is known about the stimuli elicited upon such pathogen host-cell interactions. Here, we report that type IV pili (Tfp)-producing Neisseria gonorrhoeae (P+GC) induces an immediate recruitment of caveolin-1 (Cav1) in the host cell, which subsequently prevents bacterial internalization by triggering cytoskeletal rearrangements via downstream phosphotyrosine signaling. A broad and unbiased analysis of potential interaction partners for tyrosine-phosphorylated Cav1 revealed a direct interaction with the Rho-family guanine nucleotide exchange factor Vav2. Both Vav2 and its substrate, the small GTPase RhoA, were found to play a direct role in the Cav1-mediated prevention of bacterial uptake. Our findings, which have been extended to enteropathogenic Escherichia coli, highlight how Tfp-producing bacteria avoid host cell uptake. Further, our data establish a mechanistic link between Cav1 phosphorylation and pathogen-induced cytoskeleton reorganization and advance our understanding of caveolin function. Like many bacterial pathogens, successful attachment of Neisseria gonorrhoeae—the causative agent of the sexually transmitted disease gonorrhoea—to its host cells depends on specialized structures on the bacterial surface called type IV pili (Tfp). Pathogen attachment induces changes within host cells that may facilitate and promote infection. In this study, we identify some of the earliest cellular signals elicited by N. gonorrhoeae during infection, which, in this case, prevent the organism from entering the cell precociously. After attachment to host cells the bacteria form microcolonies on the cell surface. Underneath these microcolonies, so-called cortical plaques form within the host cell—these contain the cytoskeleton protein actin and a range of signaling proteins. We show that N. gonorrhoeae recruits a host cell protein called caveolin-1 to the cell membrane where the bacteria are attached; here, caveloin-1 effectively impedes uptake of the bacteria by activating a signaling cascade that involves its phosphorylation on a tyrosine residue and subsequent interactions with proteins that regulate the cytoskeleton. Thus, these proteins play a pivotal role in maintaining N. gonorrhoeae in the extracellular milieu. By extrapolating our findings to another Tfp-producing bacterium, the enteropathogenic Escherichia coli, we argue that the establishment and maintenance of this extracellular state benefits certain pathogens by giving them time to express proteins required for subsequent steps of infection.
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Affiliation(s)
- Jan Peter Boettcher
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany
| | - Marieluise Kirchner
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany
| | - Yuri Churin
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany
| | - Alexis Kaushansky
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Malvika Pompaiah
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany
| | - Hans Thorn
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany
| | - Volker Brinkmann
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany
| | - Gavin MacBeath
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America
| | - Thomas F. Meyer
- Department of Molecular Biology, Max Planck Institute for Infection Biology, Berlin, Germany
- * E-mail:
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45
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Transcellular passage of Neisseria meningitidis across a polarized respiratory epithelium. Infect Immun 2010; 78:3832-47. [PMID: 20584970 DOI: 10.1128/iai.01377-09] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Neisseria meningitidis is a major cause of sepsis and meningitis but is also a common commensal, present in the nasopharynx of between 8 and 20% of healthy individuals. During carriage, the bacterium is found on the surface of the nasopharyngeal epithelium and in deeper tissues, while to develop disease the meningococcus must spread across the respiratory epithelium and enter the systemic circulation. Therefore, investigating the pathways by which N. meningitidis crosses the epithelial barrier is relevant for understanding carriage and disease but has been hindered by the lack of appropriate models. Here, we have established a physiologically relevant model of the upper respiratory epithelial cell barrier to investigate the mechanisms responsible for traversal of N. meningitidis. Calu-3 human respiratory epithelial cells were grown on permeable cell culture membranes to form polarized monolayers of cells joined by tight junctions. We show that the meningococcus crosses the epithelial cell barrier by a transcellular route; traversal of the layer did not disrupt its integrity, and bacteria were detected within the cells of the monolayer. We demonstrate that successful traversal of the epithelial cell barrier by N. meningitidis requires expression of its type 4 pili (Tfp) and capsule and is dependent on the host cell microtubule network. The Calu-3 model should be suitable for dissecting the pathogenesis of infections caused by other respiratory pathogens, as well as the meningococcus.
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Abstract
The endothelium lining blood and lymphatic vessels is a key barrier separating body fluids from host tissues and is a major target of pathogenic bacteria. Endothelial cells are actively involved in host responses to infectious agents, producing inflammatory cytokines, controlling coagulation cascades and regulating leukocyte trafficking. In this Review, a range of bacteria and bacterial toxins are used to illustrate how pathogens establish intimate interactions with endothelial cells, triggering inflammatory responses and coagulation processes and modifying endothelial cell plasma membranes and junctions to adhere to their surfaces and then invade, cross and even disrupt the endothelial barrier.
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Crystal structure analysis reveals Pseudomonas PilY1 as an essential calcium-dependent regulator of bacterial surface motility. Proc Natl Acad Sci U S A 2009; 107:1065-70. [PMID: 20080557 DOI: 10.1073/pnas.0911616107] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Several bacterial pathogens require the "twitching" motility produced by filamentous type IV pili (T4P) to establish and maintain human infections. Two cytoplasmic ATPases function as an oscillatory motor that powers twitching motility via cycles of pilus extension and retraction. The regulation of this motor, however, has remained a mystery. We present the 2.1 A resolution crystal structure of the Pseudomonas aeruginosa pilus-biogenesis factor PilY1, and identify a single site on this protein required for bacterial translocation. The structure reveals a modified beta-propeller fold and a distinct EF-hand-like calcium-binding site conserved in pathogens with retractile T4P. We show that preventing calcium binding by PilY1 using either an exogenous calcium chelator or mutation of a single residue disrupts Pseudomonas twitching motility by eliminating surface pili. In contrast, placing a lysine in this site to mimic the charge of a bound calcium interferes with motility in the opposite manner--by producing an abundance of nonfunctional surface pili. Our data indicate that calcium binding and release by the unique loop identified in the PilY1 crystal structure controls the opposing forces of pilus extension and retraction. Thus, PilY1 is an essential, calcium-dependent regulator of bacterial twitching motility.
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Kline KA, Fälker S, Dahlberg S, Normark S, Henriques-Normark B. Bacterial adhesins in host-microbe interactions. Cell Host Microbe 2009; 5:580-92. [PMID: 19527885 DOI: 10.1016/j.chom.2009.05.011] [Citation(s) in RCA: 414] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2009] [Revised: 05/23/2009] [Accepted: 05/27/2009] [Indexed: 02/09/2023]
Abstract
Most commensal and pathogenic bacteria interacting with eukaryotic hosts express adhesive molecules on their surfaces that promote interaction with host cell receptors or with soluble macromolecules. Even though bacterial attachment to epithelial cells may be beneficial for bacterial colonization, adhesion may come at a cost because bacterial attachment to immune cells can facilitate phagocytosis and clearing. Many pathogenic bacteria have solved this dilemma by producing an antiphagocytic surface layer usually consisting of polysaccharide and by expressing their adhesins on polymeric structures that extend out from the cell surface. In this review, we will focus on the interaction between bacterial adhesins and the host, with an emphasis on pilus-like structures.
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Affiliation(s)
- Kimberly A Kline
- Swedish Institute for Infectious Disease Control and Department of Microbiology, Tumor, and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
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Coureuil M, Mikaty G, Miller F, Lécuyer H, Bernard C, Bourdoulous S, Duménil G, Mège RM, Weksler BB, Romero IA, Couraud PO, Nassif X. Meningococcal type IV pili recruit the polarity complex to cross the brain endothelium. Science 2009; 325:83-7. [PMID: 19520910 DOI: 10.1126/science.1173196] [Citation(s) in RCA: 166] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Type IV pili mediate the initial interaction of many bacterial pathogens with their host cells. In Neisseria meningitidis, the causative agent of cerebrospinal meningitis, type IV pili-mediated adhesion to brain endothelial cells is required for bacteria to cross the blood-brain barrier. Here, type IV pili-mediated adhesion of N. meningitidis to human brain endothelial cells was found to recruit the Par3/Par6/PKCzeta polarity complex that plays a pivotal role in the establishment of eukaryotic cell polarity and the formation of intercellular junctions. This recruitment leads to the formation of ectopic intercellular junctional domains at the site of bacteria-host cell interaction and a subsequent depletion of junctional proteins at the cell-cell interface with opening of the intercellular junctions of the brain-endothelial interface.
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Affiliation(s)
- Mathieu Coureuil
- Université Paris Descartes, Faculté de Médecine, INSERM (U-570), 75015 Paris, France.
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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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