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Martinez FG, Zielke RA, Fougeroux CE, Li L, Sander AF, Sikora AE. Development of a Tag/Catcher-mediated capsid virus-like particle vaccine presenting the conserved Neisseria gonorrhoeae SliC antigen that blocks human lysozyme. Infect Immun 2023; 91:e0024523. [PMID: 37916806 PMCID: PMC10715030 DOI: 10.1128/iai.00245-23] [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: 06/23/2023] [Accepted: 10/10/2023] [Indexed: 11/03/2023] Open
Abstract
Virus-like particles (VLPs) are promising nanotools for the development of subunit vaccines due to high immunogenicity and safety. Herein, we explored the versatile and effective Tag/Catcher-AP205 capsid VLP (cVLP) vaccine platform to address the urgent need for the development of an effective and safe vaccine against gonorrhea. The benefits of this clinically validated cVLP platform include its ability to facilitate unidirectional, high-density display of complex/full-length antigens through an effective split-protein Tag/Catcher conjugation system. To assess this modular approach for making cVLP vaccines, we used a conserved surface lipoprotein, SliC, that contributes to the Neisseria gonorrhoeae defense against human lysozyme, as a model antigen. This protein was genetically fused at the N- or C-terminus to the small peptide Tag enabling their conjugation to AP205 cVLP, displaying the complementary Catcher. We determined that SliC with the N-terminal SpyTag, N-SliC, retained lysozyme-blocking activity and could be displayed at high density on cVLPs without causing aggregation. In mice, the N-SliC-VLP vaccines, adjuvanted with AddaVax or CpG, induced significantly higher antibody titers compared to controls. In contrast, similar vaccine formulations containing monomeric SliC were non-immunogenic. Accordingly, sera from N-SliC-VLP-immunized mice also had significantly higher human complement-dependent serum bactericidal activity. Furthermore, the N-SliC-VLP vaccines administered subcutaneously with an intranasal boost elicited systemic and vaginal IgG and IgA, whereas subcutaneous delivery alone failed to induce vaginal IgA. The N-SliC-VLP with CpG (10 µg/dose) induced the most significant increase in total serum IgG and IgG3 titers, vaginal IgG and IgA, and bactericidal antibodies.
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Affiliation(s)
- Fabian G. Martinez
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon, USA
| | - Ryszard A. Zielke
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon, USA
| | | | - Lixin Li
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon, USA
| | - Adam F. Sander
- AdaptVac Aps, Hørsholm, Denmark
- Faculty of Health Science, University of Copenhagen, Copenhagen, Denmark
- Institute for Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Aleksandra E. Sikora
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, Oregon, USA
- Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, Oregon, USA
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2
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Branch AH, Stoudenmire JL, Seib KL, Cornelissen CN. Acclimation to Nutritional Immunity and Metal Intoxication Requires Zinc, Manganese, and Copper Homeostasis in the Pathogenic Neisseriae. Front Cell Infect Microbiol 2022; 12:909888. [PMID: 35846739 PMCID: PMC9280163 DOI: 10.3389/fcimb.2022.909888] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 05/18/2022] [Indexed: 12/15/2022] Open
Abstract
Neisseria gonorrhoeae and Neisseria meningitidis are human-specific pathogens in the Neisseriaceae family that can cause devastating diseases. Although both species inhabit mucosal surfaces, they cause dramatically different diseases. Despite this, they have evolved similar mechanisms to survive and thrive in a metal-restricted host. The human host restricts, or overloads, the bacterial metal nutrient supply within host cell niches to limit pathogenesis and disease progression. Thus, the pathogenic Neisseria require appropriate metal homeostasis mechanisms to acclimate to such a hostile and ever-changing host environment. This review discusses the mechanisms by which the host allocates and alters zinc, manganese, and copper levels and the ability of the pathogenic Neisseria to sense and respond to such alterations. This review will also discuss integrated metal homeostasis in N. gonorrhoeae and the significance of investigating metal interplay.
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Affiliation(s)
- Alexis Hope Branch
- Center for Translational Immunology, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, United States
| | - Julie L. Stoudenmire
- Center for Translational Immunology, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, United States
| | - Kate L. Seib
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
| | - Cynthia Nau Cornelissen
- Center for Translational Immunology, Institute for Biomedical Sciences, Georgia State University, Atlanta, GA, United States
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3
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Sunkavalli A, McClure R, Genco C. Molecular Regulatory Mechanisms Drive Emergent Pathogenetic Properties of Neisseria gonorrhoeae. Microorganisms 2022; 10:922. [PMID: 35630366 PMCID: PMC9147433 DOI: 10.3390/microorganisms10050922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/25/2022] [Accepted: 04/26/2022] [Indexed: 12/05/2022] Open
Abstract
Neisseria gonorrhoeae is the causative agent of the sexually transmitted infection (STI) gonorrhea, with an estimated 87 million annual cases worldwide. N. gonorrhoeae predominantly colonizes the male and female genital tract (FGT). In the FGT, N. gonorrhoeae confronts fluctuating levels of nutrients and oxidative and non-oxidative antimicrobial defenses of the immune system, as well as the resident microbiome. One mechanism utilized by N. gonorrhoeae to adapt to this dynamic FGT niche is to modulate gene expression primarily through DNA-binding transcriptional regulators. Here, we describe the major N. gonorrhoeae transcriptional regulators, genes under their control, and how these regulatory processes lead to pathogenic properties of N. gonorrhoeae during natural infection. We also discuss the current knowledge of the structure, function, and diversity of the FGT microbiome and its influence on gonococcal survival and transcriptional responses orchestrated by its DNA-binding regulators. We conclude with recent multi-omics data and modeling tools and their application to FGT microbiome dynamics. Understanding the strategies utilized by N. gonorrhoeae to regulate gene expression and their impact on the emergent characteristics of this pathogen during infection has the potential to identify new effective strategies to both treat and prevent gonorrhea.
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Affiliation(s)
- Ashwini Sunkavalli
- Department of Immunology, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, MA 02111, USA;
| | - Ryan McClure
- Pacific Northwest National Laboratory, Richland, WA 99354, USA;
| | - Caroline Genco
- Department of Immunology, Graduate School of Biomedical Sciences, Tufts University School of Medicine, Boston, MA 02111, USA;
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Hu S, Niu L, Wu L, Zhu X, Cai Y, Jin D, Yan L, Zhao F. Genomic analysis of Helicobacter himalayensis sp. nov. isolated from Marmota himalayana. BMC Genomics 2020; 21:826. [PMID: 33228534 PMCID: PMC7685656 DOI: 10.1186/s12864-020-07245-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 11/18/2020] [Indexed: 12/17/2022] Open
Abstract
Background Helicobacter himalayensis was isolated from Marmota himalayana in the Qinghai-Tibet Plateau, China, and is a new non-H. pylori species, with unclear taxonomy, phylogeny, and pathogenicity. Results A comparative genomic analysis was performed between the H. himalayensis type strain 80(YS1)T and other the genomes of Helicobacter species present in the National Center for Biotechnology Information (NCBI) database to explore the molecular evolution and potential pathogenicity of H. himalayensis. H. himalayensis 80(YS1)T formed a clade with H. cinaedi and H. hepaticus that was phylogenetically distant from H. pylori. The H. himalayensis genome showed extensive collinearity with H. hepaticus and H. cinaedi. However, it also revealed a low degree of genome collinearity with H. pylori. The genome of 80(YS1)T comprised 1,829,936 bp, with a 39.89% GC content, a predicted genomic island, and 1769 genes. Comparatively, H. himalayensis has more genes for functions in “cell wall/membrane/envelope biogenesis” and “coenzyme transport and metabolism” sub-branches than the other compared helicobacters, and its genome contained 42 virulence factors genes, including that encoding cytolethal distending toxin (CDT). Conclusions We characterized the H. himalayensis 80(YS1)T genome, its phylogenetic position, and its potential pathogenicity. However, further understanding of the pathogenesis of this potentially pathogenic bacterium is required, which might help to manage H. himalayensis-induced diseases. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-020-07245-y.
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Affiliation(s)
- Shoukui Hu
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Lina Niu
- Department of Pathogen Biology, School of Basic Medicine and Lifescience, Hainan Medical University, Haikou, 571101, China
| | - Lei Wu
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Xiaoxue Zhu
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Yu Cai
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China
| | - Dong Jin
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing, 102206, China
| | - Linlin Yan
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China.
| | - Fan Zhao
- Department of Clinical Laboratory, Peking University Shougang Hospital, Beijing, 100144, China.
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Sikora AE, Gomez C, Le Van A, Baarda BI, Darnell S, Martinez FG, Zielke RA, Bonventre JA, Jerse AE. A novel gonorrhea vaccine composed of MetQ lipoprotein formulated with CpG shortens experimental murine infection. Vaccine 2020; 38:8175-8184. [PMID: 33162204 DOI: 10.1016/j.vaccine.2020.10.077] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/15/2020] [Accepted: 10/23/2020] [Indexed: 11/18/2022]
Abstract
Bacterial surface lipoproteins are emerging as attractive vaccine candidates due to their biological importance and the feasibility of their large-scale production for vaccine manufacturing. The global prevalence of gonorrhea, resistance to antibiotics, and serious consequences to reproductive and neonatal health necessitate development of effective vaccines. Reverse vaccinology identified the surface-displayed L-methionine binding lipoprotein MetQ (NGO2139) and its homolog GNA1946 (NMB1946) as gonococcal and meningococcal vaccine candidates, respectively. Here, we assessed the suitability of MetQ for inclusion in a gonorrhea vaccine by examining MetQ conservation, its function inNeisseria gonorrhoeae (Ng) pathogenesis, and its ability to induce protective immune responses using a female murine model of lower genital tract infection. In-depth bioinformatics, phylogenetics and mapping the most prevalent Ng polymorphic amino acids to the GNA1946 crystal structure revealed remarkable MetQ conservation: ~97% Ng isolates worldwide possess a single MetQ variant. Mice immunized with rMetQ-CpG (n = 40), a vaccine containing a tag-free version of MetQ formulated with CpG, exhibited robust, antigen-specific antibody responses in serum and at the vaginal mucosae including IgA. Consistent with the activity of CpG as a Th1-stimulating adjuvant, the serum IgG1/IgG2a ratio of 0.38 suggested a Th1 bias. Combined data from two independent challenge experiments demonstrated that rMetQ-CpG immunized mice cleared infection faster than control animals (vehicle, p < 0.0001; CpG, p = 0.002) and had lower Ng burden (vehicle, p = 0.03; CpG, p < 0.0001). We conclude rMetQ-CpG induces a protective immune response that accelerates bacterial clearance from the murine lower genital tract and represents an attractive component of a gonorrhea subunit vaccine.
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Affiliation(s)
- Aleksandra E Sikora
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, OR 97330, United States; Vaccine and Gene Therapy Institute, Oregon Health & Science University, Beaverton, OR, United States.
| | - Carolina Gomez
- Department of Microbiology and Immunology, F. Edward Hebert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States
| | - Adriana Le Van
- Department of Microbiology and Immunology, F. Edward Hebert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States
| | - Benjamin I Baarda
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, OR 97330, United States
| | - Stephen Darnell
- Department of Microbiology and Immunology, F. Edward Hebert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States
| | - Fabian G Martinez
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, OR 97330, United States
| | - Ryszard A Zielke
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, OR 97330, United States
| | - Josephine A Bonventre
- Department of Pharmaceutical Sciences, College of Pharmacy, Oregon State University, Corvallis, OR 97330, United States
| | - Ann E Jerse
- Department of Microbiology and Immunology, F. Edward Hebert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, United States.
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6
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Russell MW, Jerse AE, Gray-Owen SD. Progress Toward a Gonococcal Vaccine: The Way Forward. Front Immunol 2019; 10:2417. [PMID: 31681305 PMCID: PMC6803597 DOI: 10.3389/fimmu.2019.02417] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 09/27/2019] [Indexed: 12/26/2022] Open
Abstract
The concept of immunizing against gonorrhea has received renewed interest because of the recent emergence of strains of Neisseria gonorrhoeae that are resistant to most currently available antibiotics, an occurrence that threatens to render gonorrhea untreatable. However, despite efforts over many decades, no vaccine has yet been successfully developed for human use, leading to pessimism over whether this goal was actually attainable. Several factors have contributed to this situation, including extensive variation of the expression and specificity of many of the gonococcal surface antigens, and the ability of N. gonorrhoeae to resist destruction by complement and other innate immune defense mechanisms. The natural host restriction of N. gonorrhoeae for humans, coupled with the absence of any definable state of immunity arising from an episode of gonorrhea, have also complicated efforts to study gonococcal pathogenesis and the host's immune responses. However, recent findings have elucidated how the gonococcus exploits and manipulates the host's immune system for its own benefit, utilizing human-specific receptors for attachment to and invasion of tissues, and subverting adaptive immune responses that might otherwise be capable of eliminating it. While no single experimental model is capable of providing all the answers, experiments utilizing human cells and tissues in vitro, various in vivo animal models, including genetically modified strains of mice, and both experimental and observational human clinical studies, have combined to yield important new insight into the immuno-pathogenesis of gonococcal infection. In turn, these have now led to novel approaches for the development of a gonococcal vaccine. Ongoing investigations utilizing all available tools are now poised to make the development of an effective human vaccine against gonorrhea an achievable goal within a foreseeable time-frame.
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Affiliation(s)
- Michael W. Russell
- Department of Microbiology and Immunology, University at Buffalo, Buffalo, NY, United States
| | - Ann E. Jerse
- Department of Microbiology and Immunology, F. Edward Herbert School of Medicine, Uniformed Services University, Bethesda, MD, United States
| | - Scott D. Gray-Owen
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
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7
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Singh VK, Singh K, Baum K. The Role of Methionine Sulfoxide Reductases in Oxidative Stress Tolerance and Virulence of Staphylococcus aureus and Other Bacteria. Antioxidants (Basel) 2018; 7:antiox7100128. [PMID: 30274148 PMCID: PMC6210949 DOI: 10.3390/antiox7100128] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 09/19/2018] [Accepted: 09/26/2018] [Indexed: 11/18/2022] Open
Abstract
Methionine sulfoxide reductases (MSRA1 and MSRB) are proteins overproduced in Staphylococcus aureus during exposure with cell wall-active antibiotics. Later studies identified the presence of two additional MSRA proteins (MSRA2 and MSRA3) in S. aureus. These MSR proteins have been characterized in many other bacteria as well. This review provides the current knowledge about the conditions and regulatory network that mimic the expression of these MSR encoding genes and their role in defense from oxidative stress and virulence.
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Affiliation(s)
- Vineet K Singh
- Department of Microbiology and Immunology, A.T. Still University of Health Sciences, Kirksville, MO 63501, USA.
| | | | - Kyle Baum
- Department of Microbiology and Immunology, A.T. Still University of Health Sciences, Kirksville, MO 63501, USA.
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8
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Rice PA, Shafer WM, Ram S, Jerse AE. Neisseria gonorrhoeae: Drug Resistance, Mouse Models, and Vaccine Development. Annu Rev Microbiol 2018; 71:665-686. [PMID: 28886683 DOI: 10.1146/annurev-micro-090816-093530] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Gonorrhea, an obligate human infection, is on the rise worldwide and gonococcal strains resistant to many antibiotics are emerging. Appropriate antimicrobial treatment and prevention, including effective vaccines, are urgently needed. To guide investigation, an experimental model of genital tract infection has been developed in female mice to study mechanisms by which Neisseria gonorrhoeae evades host-derived antimicrobial factors and to identify protective and immunosuppressive pathways. Refinements of the animal model have also improved its use as a surrogate host of human infection and accelerated the testing of novel therapeutic and prophylactic compounds against gonococcal infection. Reviewed herein are the (a) history of antibiotic usage and resistance against gonorrhea and the consequences of resistance mechanisms that may increase gonococcal fitness and therefore the potential for spread, (b) use of gonococcal infection in the animal model system to study mechanisms of pathogenesis and host defenses, and
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Affiliation(s)
- Peter A Rice
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605-4321; ,
| | - William M Shafer
- Department of Microbiology and Immunology and Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, Georgia 30322.,Laboratories of Bacterial Pathogenesis, Veterans Affairs Medical Center, Decatur, Georgia 30033;
| | - Sanjay Ram
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01605-4321; ,
| | - Ann E Jerse
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University, Bethesda, Maryland 20814-4799;
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10
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Johnson MB, Ball LM, Daily KP, Martin JN, Columbus L, Criss AK. Opa+ Neisseria gonorrhoeae exhibits reduced survival in human neutrophils via Src family kinase-mediated bacterial trafficking into mature phagolysosomes. Cell Microbiol 2014; 17:648-65. [PMID: 25346239 DOI: 10.1111/cmi.12389] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 10/01/2014] [Accepted: 10/22/2014] [Indexed: 01/05/2023]
Abstract
During gonorrhoeal infection, there is a heterogeneous population of Neisseria gonorrhoeae (Gc) varied in their expression of opacity-associated (Opa) proteins. While Opa proteins are important for bacterial attachment and invasion of epithelial cells, Opa+ Gc has a survival defect after exposure to neutrophils. Here, we use constitutively Opa- and OpaD+ Gc in strain background FA1090 to show that Opa+ Gc is more sensitive to killing inside adherent, chemokine-treated primary human neutrophils due to increased bacterial residence in mature, degradative phagolysosomes that contain primary and secondary granule antimicrobial contents. Although Opa+ Gc stimulates a potent oxidative burst, neutrophil killing of Opa+ Gc was instead attributable to non-oxidative components, particularly neutrophil proteases and the bactericidal/permeability-increasing protein. Blocking interaction of Opa+ Gc with carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) or inhibiting Src family kinase signalling, which is downstream of CEACAM activation, enhanced the survival of Opa+ Gc in neutrophils. Src family kinase signalling was required for fusion of Gc phagosomes with primary granules to generate mature phagolysosomes. Conversely, ectopic activation of Src family kinases or coinfection with Opa+ Gc resulted in decreased survival of Opa- Gc in neutrophils. From these results, we conclude that Opa protein expression is an important modulator of Gc survival characteristics in neutrophils by influencing phagosome dynamics and thus bacterial exposure to neutrophils' full antimicrobial arsenal.
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Affiliation(s)
- M Brittany Johnson
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA
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11
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Phosphoethanolamine decoration of Neisseria gonorrhoeae lipid A plays a dual immunostimulatory and protective role during experimental genital tract infection. Infect Immun 2014; 82:2170-9. [PMID: 24686069 DOI: 10.1128/iai.01504-14] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The induction of an intense inflammatory response by Neisseria gonorrhoeae and the persistence of this pathogen in the presence of innate effectors is a fascinating aspect of gonorrhea. Phosphoethanolamine (PEA) decoration of lipid A increases gonococcal resistance to complement-mediated bacteriolysis and cationic antimicrobial peptides (CAMPs), and recently we reported that wild-type N. gonorrhoeae strain FA1090 has a survival advantage relative to a PEA transferase A (lptA) mutant in the human urethral-challenge and murine lower genital tract infection models. Here we tested the immunostimulatory role of this lipid A modification. Purified lipooligosaccharide (LOS) containing lipid A devoid of the PEA modification and an lptA mutant of strain FA19 induced significantly lower levels of NF-κB in human embryonic kidney Toll-like receptor 4 (TLR4) cells and murine embryonic fibroblasts than wild-type LOS of the parent strain. Moreover, vaginal proinflammatory cytokines and chemokines were not elevated in female mice infected with the isogenic lptA mutant, in contrast to mice infected with the wild-type and complemented lptA mutant bacteria. We also demonstrated that lptA mutant bacteria were more susceptible to human and murine cathelicidins due to increased binding by these peptides and that the differential induction of NF-κB by wild-type and unmodified lipid A was more pronounced in the presence of CAMPs. This work demonstrates that PEA decoration of lipid A plays both protective and immunostimulatory roles and that host-derived CAMPs may further reduce the capacity of PEA-deficient lipid A to interact with TLR4 during infection.
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12
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Assembly of NADPH oxidase in human neutrophils is modulated by the opacity-associated protein expression State of Neisseria gonorrhoeae. Infect Immun 2013; 82:1036-44. [PMID: 24343654 DOI: 10.1128/iai.00881-13] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Neisseria gonorrhoeae (the gonococcus, Gc) triggers a potent inflammatory response and recruitment of neutrophils to the site of infection. Gc survives exposure to neutrophils despite these cells' antimicrobial products, such as reactive oxygen species (ROS). ROS production in neutrophils is initiated by NADPH oxidase, which converts oxygen into superoxide. The subunits of NADPH oxidase are spatially separated between granules (gp91(phox)/p22(phox)) and the cytoplasm (p47(phox), p67(phox), and p40(phox)). Activation of neutrophils promotes the coassembly of NADPH oxidase subunits at phagosome and/or plasma membranes. While Gc-expressing opacity-associated (Opa) proteins can induce neutrophils to produce ROS, Opa-negative (Opa-) Gc does not stimulate neutrophil ROS production. Using constitutively Opa- and OpaD-positive (OpaD+) Gc bacteria in strain FA1090, we now show that the difference in ROS production levels in primary human neutrophils between these backgrounds can be attributed to differential assembly of NADPH oxidase. Neutrophils infected with Opa- Gc showed limited translocation of NADPH oxidase cytoplasmic subunits to cellular membranes, including the bacterial phagosome. In contrast, these subunits rapidly translocated to neutrophil membranes following infection with OpaD+ Gc. gp91(phox) and p22(phox) were recruited to Gc phagosomes regardless of bacterial Opa expression. These results suggest that Opa- Gc interferes with the recruitment of neutrophil NADPH oxidase cytoplasmic subunits to membranes, in particular, the p47(phox) "organizing" subunit, to prevent assembly of the holoenzyme, resulting in an absence of the oxidative burst.
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13
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Djoko KY, McEwan AG. Antimicrobial action of copper is amplified via inhibition of heme biosynthesis. ACS Chem Biol 2013; 8:2217-23. [PMID: 23895035 DOI: 10.1021/cb4002443] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Copper (Cu) is a potent antimicrobial agent. Its use as a disinfectant goes back to antiquity, but this metal ion has recently emerged to have a physiological role in the host innate immune response. Recent studies have identified iron-sulfur containing proteins as key targets for inhibition by Cu. However, the way in these effects at the molecular level translate into a global effect on cell physiology is not fully understood. Here, we provide a new insight into the way in which Cu poisons bacteria. Using a copA mutant of the obligate human pathogen Neisseria gonorrhoeae that lacks a Cu efflux pump, we showed that Cu overloading led to an increased sensitivity to hydrogen peroxide. However, instead of promoting disproportionation of H2O2 via Fenton chemistry, Cu treatment led to an increased lifetime of H2O2 in cultures as a result of a marked decrease in catalase activity. We showed that this observation correlated with a loss of intracellular heme. We further established that Cu inhibited the pathway for heme biosynthesis. We proposed that this impaired ability to produce heme during Cu stress would lead to the failure to activate hemoproteins that participate in key processes, such as the detoxification of various reactive oxygen and nitrogen species, and aerobic respiration. The impact would be a global disruption of cellular biochemistry and an amplified Cu toxicity.
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Affiliation(s)
- Karrera Y. Djoko
- School of Chemistry and Molecular
Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Alastair G. McEwan
- School of Chemistry and Molecular
Biosciences, The University of Queensland, St Lucia, Queensland 4072, Australia
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14
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Johnson MB, Criss AK. Neisseria gonorrhoeae phagosomes delay fusion with primary granules to enhance bacterial survival inside human neutrophils. Cell Microbiol 2013; 15:1323-40. [PMID: 23374609 PMCID: PMC3713093 DOI: 10.1111/cmi.12117] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 01/11/2013] [Accepted: 01/27/2013] [Indexed: 12/21/2022]
Abstract
Symptomatic infection with Neisseria gonorrhoeae (Gc) promotes inflammation driven by polymorphonuclear leucocytes (PMNs, neutrophils), yet some Gc survive PMN exposure during infection. Here we report a novel mechanism of gonococcal resistance to PMNs: Gc phagosomes avoid maturation into phagolysosomes by delayed fusion with primary (azurophilic) granules, which contain antimicrobial components including serine proteases. Reduced phagosome-primary granule fusion was observed in gonorrheal exudates and human PMNs infected ex vivo. Delayed phagosome-granule fusion could be overcome by opsonizing Gc with immunoglobulin. Using bacterial viability dyes along with antibodies to primary granules revealed that Gc survival in PMNs correlated with early residence in primary granule-negative phagosomes. However, when Gc was killed prior to PMN exposure, dead bacteria were also found in primary granule-negative phagosomes. These results suggest that Gc surface characteristics, rather than active bacterial processes, influence phagosome maturation and that Gc death inside PMNs occurs after phagosome-granule fusion. Ectopically increasing primary granule-phagosome fusion, by immunoglobulin opsonization or PMN treatment with lysophosphatidylcholine, reduced intracellular Gc viability, which was attributed in part to serine protease activity. We conclude that one method for Gc to avoid PMN clearance in acute gonorrhoea is by delaying primary granule-phagosome fusion, thus preventing formation of a degradative phagolysosome.
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Affiliation(s)
- M. Brittany Johnson
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Alison K. Criss
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
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15
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Neisseria gonorrhoeae metalloprotease NGO1686 is required for full piliation, and piliation is required for resistance to H2O2- and neutrophil-mediated killing. mBio 2013; 4:mBio.00399-13. [PMID: 23839218 PMCID: PMC3735123 DOI: 10.1128/mbio.00399-13] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The sexually transmitted infection gonorrhea is caused exclusively by the human-specific pathogen Neisseria gonorrhoeae. Type IV pili are an essential virulence factor uniformly expressed on clinical gonococcal isolates and are required for several aspects of gonococcal pathogenesis, including adherence to host tissues, autoagglutination, twitching motility, and the uptake of DNA during transformation. Symptomatic gonococcal infection is characterized by the influx of neutrophils or polymorphonuclear leukocytes (PMNs) to the site of infection. PMNs are a key component of gonococcal pathogenesis, mediating the innate immune response through the use of oxidative and nonoxidative killing mechanisms. The M23B family zinc metallopeptidase NGO1686 is required for gonococci to survive oxidative killing by H2O2- and PMN-mediated killing through unknown mechanisms, but the only known target of NGO1686 is peptidoglycan. We report that the effect of NGO1686 on survival after exposure to H2O2 and PMNs is mediated through its role in elaborating pili and that nonpiliated mutants of N. gonorrhoeae are less resistant to killing by H2O2, LL-37, and PMNs than the corresponding piliated strains. These findings add to the various virulence-associated functions attributable to gonococcal pili and may explain the selection basis for piliation in clinical isolates of N. gonorrhoeae. IMPORTANCE Successful infectious agents need to overcome host defense systems to establish infection. We show that the Neisseria pilus, a major virulence factor of this organism, which causes gonorrhea, helps protect the bacterium from two major killing mechanisms used by the host to combat infections. We also show that to express the pilus, an enzyme needs to partially degrade the cell wall of the bacterium.
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Constitutively Opa-expressing and Opa-deficient neisseria gonorrhoeae strains differentially stimulate and survive exposure to human neutrophils. J Bacteriol 2013; 195:2982-90. [PMID: 23625842 DOI: 10.1128/jb.00171-13] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Neisseria gonorrhoeae (the gonococcus [Gc]) opacity-associated (Opa) proteins mediate bacterial binding and internalization by human epithelial cells and neutrophils (polymorphonuclear leukocytes [PMNs]). Investigating the contribution of Opa proteins to gonococcal pathogenesis is complicated by high-frequency phase variation of the opa genes. We therefore engineered a derivative of Gc strain FA1090 in which all opa genes were deleted in frame, termed Opaless. Opaless Gc remained uniformly Opa negative (Opa(-)), whereas cultures of predominantly Opa(-) parental Gc and an intermediate lacking the "translucent" subset of opa genes (ΔopaBEGK) stochastically gave rise to Opa-positive (Opa(+)) bacterial colonies. Loss of Opa expression did not affect Gc growth. Opaless Gc survived exposure to primary human PMNs and suppressed the PMN oxidative burst akin to parental, Opa(-) bacteria. Notably, unopsonized Opaless Gc was internalized by adherent, chemokine-primed, primary human PMNs, by an actin-dependent process. When a non-phase-variable, in-frame allele of FA1090 opaD was reintroduced into Opaless Gc, the bacteria induced the PMN oxidative burst, and OpaD(+) Gc survived less well after exposure to PMNs compared to Opa(-) bacteria. These derivatives provide a robust system for assessing the role of Opa proteins in Gc biology.
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Wang Y, Yi L, Wu Z, Shao J, Liu G, Fan H, Zhang W, Lu C. Comparative proteomic analysis of Streptococcus suis biofilms and planktonic cells that identified biofilm infection-related immunogenic proteins. PLoS One 2012; 7:e33371. [PMID: 22514606 PMCID: PMC3326019 DOI: 10.1371/journal.pone.0033371] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2011] [Accepted: 02/13/2012] [Indexed: 12/08/2022] Open
Abstract
Streptococcus suis (SS) is a zoonotic pathogen that causes severe disease symptoms in pigs and humans. Biofilms of SS bind to extracellular matrix proteins in both endothelial and epithelial cells and cause persistent infections. In this study, the differences in the protein expression profiles of SS grown either as planktonic cells or biofilms were identified using comparative proteomic analysis. The results revealed the existence of 13 proteins of varying amounts, among which six were upregulated and seven were downregulated in the Streptococcus biofilm compared with the planktonic controls. The convalescent serum from mini-pig, challenged with SS, was applied in a Western blot assay to visualize all proteins from the biofilm that were grown in vitro and separated by two-dimensional gel electrophoresis. A total of 10 immunoreactive protein spots corresponding to nine unique proteins were identified by MALDI-TOF/TOF-MS. Of these nine proteins, five (Manganese-dependent superoxide dismutase, UDP-N-acetylglucosamine 1-carboxyvinyltransferase, ornithine carbamoyltransferase, phosphoglycerate kinase, Hypothetical protein SSU05_0403) had no previously reported immunogenic properties in SS to our knowledge. The remaining four immunogenic proteins (glyceraldehyde-3-phosphate dehydrogenase, hemolysin, pyruvate dehydrogenase and DnaK) were identified under both planktonic and biofilm growth conditions. In conclusion, the protein expression pattern of SS, grown as biofilm, was different from the SS grown as planktonic cells. These five immunogenic proteins that were specific to SS biofilm cells may potentially be targeted as vaccine candidates to protect against SS biofilm infections. The four proteins common to both biofilm and planktonic cells can be targeted as vaccine candidates to protect against both biofilm and acute infections.
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Affiliation(s)
- Yang Wang
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China
| | - Li Yi
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Zongfu Wu
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Jing Shao
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Guangjin Liu
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Hongjie Fan
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
| | - Wei Zhang
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
- * E-mail: (WZ); (CL)
| | - Chengping Lu
- Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing Agricultural University, Nanjing, China
- * E-mail: (WZ); (CL)
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18
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A bacterial siren song: intimate interactions between Neisseria and neutrophils. Nat Rev Microbiol 2012; 10:178-90. [PMID: 22290508 DOI: 10.1038/nrmicro2713] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Neisseria gonorrhoeae and Neisseria meningitidis are Gram-negative bacterial pathogens that are exquisitely adapted for growth at human mucosal surfaces and for efficient transmission between hosts. One factor that is essential to neisserial pathogenesis is the interaction between the bacteria and neutrophils, which are recruited in high numbers during infection. Although this vigorous host response could simply reflect effective immune recognition of the bacteria, there is mounting evidence that in fact these obligate human pathogens manipulate the innate immune response to promote infectious processes. This Review summarizes the mechanisms used by pathogenic neisseriae to resist and modulate the antimicrobial activities of neutrophils. It also details some of the major outstanding questions about the Neisseria-neutrophil relationship and proposes potential benefits of this relationship for the pathogen.
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Jerse AE, Wu H, Packiam M, Vonck RA, Begum AA, Garvin LE. Estradiol-Treated Female Mice as Surrogate Hosts for Neisseria gonorrhoeae Genital Tract Infections. Front Microbiol 2011; 2:107. [PMID: 21747807 PMCID: PMC3129519 DOI: 10.3389/fmicb.2011.00107] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 04/28/2011] [Indexed: 12/16/2022] Open
Abstract
Historically, animal modeling of gonorrhea has been hampered by the exclusive adaptation of Neisseria gonorrhoeae to humans. Genital tract infection can be established in female mice that are treated with 17β-estradiol, however, and many features of experimental murine infection mimic human infection. Here we review the colonization kinetics and host response to experimental murine gonococcal infection, including mouse strain differences and evidence that IL-17 responses, toll-like receptor 4, and T regulatory cells play a role in infection. We also discuss the strengths and limitations of the mouse system and the potential of transgenic mice to circumvent host restrictions. Additionally, we review studies with genetically defined mutants that demonstrated a role for sialyltransferase and the MtrC-MtrD-MtrE active efflux pump in evading innate defenses in vivo, but not for factors hypothesized to protect against the phagocytic respiratory burst and H(2)O(2)-producing lactobacilli. Studies using estradiol-treated mice have also revealed the existence of non-host-restricted iron sources in the female genital tract and the influence of hormonal factors on colonization kinetics and selection for opacity (Opa) protein expression. Recent work by others with estradiol-treated mice that are transgenic for human carcinoembryonic adhesion molecules (CEACAMs) supports a role for Opa proteins in enhancing cellular attachment and thus reduced shedding of N. gonorrhoeae. Finally we discuss the use of the mouse model in product testing and a recently developed gonorrhea chlamydia coinfection model.
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Affiliation(s)
- Ann E Jerse
- Department of Microbiology and Immunology, F. Edward Hebert School of Medicine, Uniformed Services University Bethesda, MD, USA
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20
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Johnson MB, Criss AK. Resistance of Neisseria gonorrhoeae to neutrophils. Front Microbiol 2011; 2:77. [PMID: 21747795 PMCID: PMC3128980 DOI: 10.3389/fmicb.2011.00077] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Accepted: 03/31/2011] [Indexed: 01/04/2023] Open
Abstract
Infection with the human-specific bacterial pathogen Neisseria gonorrhoeae triggers a potent, local inflammatory response driven by polymorphonuclear leukocytes (neutrophils or PMNs). PMNs are terminally differentiated phagocytic cells that are a vital component of the host innate immune response and are the first responders to bacterial and fungal infections. PMNs possess a diverse arsenal of components to combat microorganisms, including the production of reactive oxygen species and release of degradative enzymes and antimicrobial peptides. Despite numerous PMNs at the site of gonococcal infection, N. gonorrhoeae can be cultured from the PMN-rich exudates of individuals with acute gonorrhea, indicating that some bacteria resist killing by neutrophils. The contribution of PMNs to gonorrheal pathogenesis has been modeled in vivo by human male urethral challenge and murine female genital inoculation and in vitro using isolated primary PMNs or PMN-derived cell lines. These systems reveal that some gonococci survive and replicate within PMNs and suggest that gonococci defend themselves against PMNs in two ways: they express virulence factors that defend against PMNs' oxidative and non-oxidative antimicrobial components, and they modulate the ability of PMNs to phagocytose gonococci and to release antimicrobial components. In this review, we will highlight the varied and complementary approaches used by N. gonorrhoeae to resist clearance by human PMNs, with an emphasis on gonococcal gene products that modulate bacterial-PMN interactions. Understanding how some gonococci survive exposure to PMNs will help guide future initiatives for combating gonorrheal disease.
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Affiliation(s)
| | - Alison K. Criss
- Department of Microbiology, University of VirginiaCharlottesville, VA, USA
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21
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Chlamydial infection increases gonococcal colonization in a novel murine coinfection model. Infect Immun 2011; 79:1566-77. [PMID: 21245268 DOI: 10.1128/iai.01155-10] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Genital tract infections caused by Neisseria gonorrhoeae and Chlamydia trachomatis serovars D to K occur at high incidence in many areas of the world. Despite high rates of coinfection with these pathogens, investigations of host-parasite interactions have focused on each pathogen individually. We describe here a coinfection model in which female BALB/c mice were first infected with the mouse Chlamydia species C. muridarum and then inoculated with N. gonorrhoeae following treatment with water-soluble 17β-estradiol to promote long-term gonococcal infection. Viable gonococci and chlamydiae were recovered for an average of 8 to 10 days, and diplococci and chlamydial inclusions were observed in lower genital tract tissue by immunohistochemical staining. Estradiol treatment reduced proinflammatory cytokine and chemokine levels in chlamydia-infected mice; however, coinfected mice had a higher percentage of vaginal neutrophils compared to mice infected with either pathogen alone. We detected no difference in pathogen-specific antibody levels due to coinfection. Interestingly, significantly more gonococci were recovered from coinfected mice compared to mice infected with N. gonorrhoeae alone. We found no evidence that C. muridarum increases gonococcal adherence to, or invasion of, immortalized murine epithelial cells. However, increased vaginal concentrations of inflammatory mediators macrophage inflammatory protein 2 and tumor necrosis factor alpha were detected in C. muridarum-infected mice prior to inoculation with N. gonorrhoeae concurrently with the downregulation of cathelicidin-related antimicrobial peptide and secretory leukocyte peptidase inhibitor genes. We conclude that female mice can be successfully infected with both C. muridarum and N. gonorrhoeae and that chlamydia-induced alterations in host innate responses may enhance gonococcal infection.
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van Alen T, Claus H, Zahedi RP, Groh J, Blazyca H, Lappann M, Sickmann A, Vogel U. Comparative proteomic analysis of biofilm and planktonic cells of Neisseria meningitidis. Proteomics 2010; 10:4512-21. [PMID: 21136603 DOI: 10.1002/pmic.201000267] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Neisseria meningitidis is a commensal of the human nasopharynx occasionally causing invasive disease. In vitro biofilms have been employed to model meningococcal carriage. A proteomic analysis of meningococcal biofilms was conducted and metabolic changes related to oxygen and nutrient limitation and upregulation of proteins involved in ROS defense were observed. The upregulated MntC which protects against ROS was shown to be required for meningococcal biofilm formation, but not for planktonic growth. ROS-induced proteomic changes might train the biofilm to cope with immune effectors.
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Affiliation(s)
- Tessa van Alen
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
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23
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Stork M, Bos MP, Jongerius I, de Kok N, Schilders I, Weynants VE, Poolman JT, Tommassen J. An outer membrane receptor of Neisseria meningitidis involved in zinc acquisition with vaccine potential. PLoS Pathog 2010; 6:e1000969. [PMID: 20617164 PMCID: PMC2895646 DOI: 10.1371/journal.ppat.1000969] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Accepted: 05/27/2010] [Indexed: 12/03/2022] Open
Abstract
Since the concentration of free iron in the human host is low, efficient iron-acquisition mechanisms constitute important virulence factors for pathogenic bacteria. In Gram-negative bacteria, TonB-dependent outer membrane receptors are implicated in iron acquisition. It is far less clear how other metals that are also scarce in the human host are transported across the bacterial outer membrane. With the aim of identifying novel vaccine candidates, we characterized in this study a hitherto unknown receptor in Neisseria meningitidis. We demonstrate that this receptor, designated ZnuD, is produced under zinc limitation and that it is involved in the uptake of zinc. Upon immunization of mice, it was capable of inducing bactericidal antibodies and we could detect ZnuD-specific antibodies in human convalescent patient sera. ZnuD is highly conserved among N. meningitidis isolates and homologues of the protein are found in many other Gram-negative pathogens, particularly in those residing in the respiratory tract. We conclude that ZnuD constitutes a promising candidate for the development of a vaccine against meningococcal disease for which no effective universal vaccine is available. Furthermore, the results suggest that receptor-mediated zinc uptake represents a novel virulence mechanism that is particularly important for bacterial survival in the respiratory tract. The outer membrane protects Gram-negative bacteria against harmful compounds from the environment. Nutrients usually pass this barrier by passive diffusion via pore-forming proteins. However, nutrients that are scarce in the environment are taken up via an active, receptor-mediated process. The vast majority of Gram-negative bacterial receptors described to date are involved in iron acquisition. Since free iron is scarce in the human host, these receptors constitute important virulence factors. In a search for putative vaccine components, we have characterized here a new receptor of Neisseria meningitidis, a resident of the nasopharynx that occasionally causes sepsis and meningitis. We show that expression of this receptor is induced under zinc limitation and that the protein is involved in the uptake of zinc. Homologues of this protein are present in many other Gram-negative pathogens, particularly in those residing in the respiratory tract, suggesting that receptor-mediated zinc acquisition is important for bacteria residing in this niche. We also found that the protein is highly conserved among N. meningitidis isolates and that it induces bactericidal antibodies upon immunization of mice. Therefore, the protein appears an excellent candidate for the development of a vaccine against N. meningitidis, for which no universal vaccine is available yet.
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Affiliation(s)
- Michiel Stork
- Department of Molecular Microbiology, Utrecht University, Utrecht, The Netherlands
| | - Martine P. Bos
- Department of Molecular Microbiology, Utrecht University, Utrecht, The Netherlands
| | - Ilse Jongerius
- Department of Molecular Microbiology, Utrecht University, Utrecht, The Netherlands
| | - Natasja de Kok
- Department of Molecular Microbiology, Utrecht University, Utrecht, The Netherlands
| | - Ingrid Schilders
- Department of Molecular Microbiology, Utrecht University, Utrecht, The Netherlands
| | | | | | - Jan Tommassen
- Department of Molecular Microbiology, Utrecht University, Utrecht, The Netherlands
- * E-mail:
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24
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Feinen B, Jerse AE, Gaffen SL, Russell MW. Critical role of Th17 responses in a murine model of Neisseria gonorrhoeae genital infection. Mucosal Immunol 2010; 3:312-21. [PMID: 20107432 PMCID: PMC2857675 DOI: 10.1038/mi.2009.139] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Host immune responses, including the characteristic influx of neutrophils, against Neisseria gonorrhoeae are poorly understood; adaptive immunity is minimal and non-protective. We hypothesize that N. gonorrhoeae selectively elicits Th17-dependent responses, which trigger innate defense mechanisms, including neutrophils and antimicrobial proteins, that it can resist. We found that N. gonorrhoeae induced the production of interleukin-17 (IL-17) in mouse T-cells and Th17-inducing cytokines in mouse and human APCs in vitro. IL-17 was induced in the iliac lymph nodes in vivo in a female mouse model of genital tract gonococcal infection. Antibody blockade of IL-17 or deletion of the major IL-17 receptor (IL-17R) in IL-17RA(KO) mice led to prolonged infection and diminished neutrophil influx. Genital tract tissue from IL-17RA(KO) mice showed reduced production of neutrophil-attractant chemokines in response to culture with N. gonorrhoeae. These results imply a crucial role for IL-17 and Th17 cells in the immune response to N. gonorrhoeae.
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MESH Headings
- Animals
- Antibodies/immunology
- Antibodies/pharmacology
- Disease Models, Animal
- Female
- Gonorrhea/genetics
- Gonorrhea/immunology
- Gonorrhea/metabolism
- Gonorrhea/pathology
- Humans
- Immunity, Innate
- Interleukin-17/genetics
- Interleukin-17/immunology
- Interleukin-17/metabolism
- Lymph Nodes/immunology
- Lymph Nodes/metabolism
- Lymph Nodes/pathology
- Mice
- Mice, Inbred BALB C
- Mice, Knockout
- Neisseria gonorrhoeae/immunology
- Neutrophil Infiltration/drug effects
- Neutrophil Infiltration/genetics
- Neutrophil Infiltration/immunology
- Neutrophils/immunology
- Neutrophils/metabolism
- Neutrophils/pathology
- Receptors, Interleukin-17/antagonists & inhibitors
- Receptors, Interleukin-17/genetics
- Receptors, Interleukin-17/immunology
- Receptors, Interleukin-17/metabolism
- T-Lymphocytes, Helper-Inducer/immunology
- T-Lymphocytes, Helper-Inducer/metabolism
- T-Lymphocytes, Helper-Inducer/pathology
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Affiliation(s)
- Brandon Feinen
- Department of Microbiology and Immunology, and Witebsky Center for Microbial Pathogenesis and Immunology, University at Buffalo, Buffalo, NY
| | - Ann E. Jerse
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD
| | - Sarah L. Gaffen
- Division of Rheumatology and Clinical Immunology, University of Pittsburgh, Pittsburgh, PA
| | - Michael W. Russell
- Department of Microbiology and Immunology, and Witebsky Center for Microbial Pathogenesis and Immunology, University at Buffalo, Buffalo, NY
- Department of Oral Biology, University at Buffalo, Buffalo, NY
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25
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Cole JG, Fulcher NB, Jerse AE. Opacity proteins increase Neisseria gonorrhoeae fitness in the female genital tract due to a factor under ovarian control. Infect Immun 2010; 78:1629-41. [PMID: 20100859 PMCID: PMC2849431 DOI: 10.1128/iai.00996-09] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 10/14/2009] [Accepted: 01/19/2010] [Indexed: 12/25/2022] Open
Abstract
The neisserial opacity (Opa) proteins are a family of antigenically distinct outer membrane proteins that undergo phase-variable expression. Opa(+) variants of Neisseria gonorrhoeae strain FA1090 are selected in a cyclical pattern from the lower genital tract of estradiol-treated mice. Here we show that cyclical recovery of Opa(+) gonococci does not occur in ovariectomized mice; therefore, the reproductive cycle plays a role in the selection kinetics in vivo. As predicted by the selection pattern shown by wild-type gonococci, we demonstrated that a constitutive Opa-expressing strain was more fit than an Opa-deficient mutant in the early and late phases of infection. We found no evidence that Opa-mediated colonization selects for Opa(+) variants during murine infection based on adherence assays with cultured murine epithelial cells. We also tested the hypothesis that complement selects for Opa protein expression during infection. Although some Opa(+) variants of a serum-sensitive derivative of strain FA1090 were more resistant to the bactericidal activity of normal human serum, selection for Opa expression was not abrogated in C3-depleted mice. Finally, as previously reported, Opa(+) gonococci were more sensitive to serine proteases. Thus, proteases or protease inhibitors may contribute to the observed in vivo selection pattern. We concluded that Opa proteins promote persistence of N. gonorrhoeae in the female genital tract and that opa gene phase variation allows gonococci to evade or capitalize upon unidentified host factors of the mammalian reproductive cycle. This work revealed an intimate interaction between pathogen and host and provides evidence that hormonally related factors shape bacterial adaptation.
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Affiliation(s)
- Jessica G. Cole
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology and Immunology, University of North Carolina, School of Medicine, Chapel Hill, North Carolina 27278
| | - Nanette B. Fulcher
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology and Immunology, University of North Carolina, School of Medicine, Chapel Hill, North Carolina 27278
| | - Ann E. Jerse
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, Department of Microbiology and Immunology, University of North Carolina, School of Medicine, Chapel Hill, North Carolina 27278
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26
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Mouse strain-dependent differences in susceptibility to Neisseria gonorrhoeae infection and induction of innate immune responses. Infect Immun 2009; 78:433-40. [PMID: 19901062 DOI: 10.1128/iai.00711-09] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Acute gonorrhea in women is characterized by a mucopurulent exudate that contains polymorphonuclear leukocytes (PMNs) with intracellular gonococci. Asymptomatic infections are also common. Information on the innate response to Neisseria gonorrhoeae in women is limited to studies with cultured cells, isolated immune cells, and analyses of cervicovaginal fluids. 17beta-Estradiol-treated BALB/c mice can be experimentally infected with N. gonorrhoeae, and a vaginal PMN influx occurs in 50 to 80% of mice. Here, we compared the colonization loads and proinflammatory responses of BALB/c, C57BL/6 and C3H/HeN mice to N. gonorrhoeae. BALB/c and C57BL/6 mice were colonized at similar levels following inoculation with 10(6) CFU of N. gonorrhoeae. BALB/c, but not C57BL/6, mice exhibited a marked vaginal PMN influx. Tumor necrosis factor alpha, interleukin-6, macrophage inflammatory protein 2 (MIP-2), and keratinocyte-derived chemokine were elevated in vaginal secretions from infected BALB/c mice, but not in those from C57BL/6 mice. MIP-2 levels positively correlated with a vaginal PMN influx. In contrast to BALB/c and C57BL/6 mice, C3H/HeN mice were resistant to infection, and there was no evidence of an inflammatory response. We conclude that N. gonorrhoeae causes a productive infection in BALB/c mice that is characterized by the induction of proinflammatory cytokines and chemokines and the recruitment of PMNs. Infection of C57BL/6 mice, in contrast, is more similar to asymptomatic infection. C3H/HeN mice are inherently resistant to N. gonorrhoeae infection, and this resistance is not due to an overwhelming inflammatory response to infection. Host genetic factors can therefore impact susceptibility and the immune response to N. gonorrhoeae.
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27
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Criss AK, Katz BZ, Seifert HS. Resistance of Neisseria gonorrhoeae to non-oxidative killing by adherent human polymorphonuclear leucocytes. Cell Microbiol 2009; 11:1074-87. [PMID: 19290914 DOI: 10.1111/j.1462-5822.2009.01308.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Symptomatic infection with Neisseria gonorrhoeae (Gc) is characterized by abundant neutrophil (PMN, polymorphonuclear leucocyte) influx, but PMNs cannot clear initial infection, indicating that Gc possess defences against PMN challenge. In this study, survival of liquid-grown Gc was monitored after synchronous infection of adherent, interleukin 8-treated human PMNs. 40-70% of FA1090 Gc survived 1 h of PMN exposure, after which bacterial numbers increased. Assays with bacterial viability dyes along with soybean lectin to detect extracellular Gc revealed that a subset of both intracellular and extracellular PMN-associated Gc were viable. Gc survival was unaffected in PMNs chemically or genetically deficient for producing reactive oxygen species (ROS). This result held true even for OpaB+ Gc, which stimulate neutrophil ROS production. Catalase- and RecA-deficient Gc, which are more sensitive to ROS in vitro, had no PMN survival defect. recN and ngo1686 mutant Gc also exhibit increased sensitivity to ROS and PMNs, but survival of these mutants was not rescued in ROS-deficient cells. The ngo1686 mutant showed increased sensitivity to extracellular but not intracellular PMN killing. We conclude that Gc are remarkably resistant to PMN killing, killing occurs independently of neutrophil ROS production and Ngo1686 and RecN defend Gc from non-oxidative PMN antimicrobial factors.
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Affiliation(s)
- Alison K Criss
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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