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Khan I, Bai Y, Zha L, Ullah N, Ullah H, Shah SRH, Sun H, Zhang C. Mechanism of the Gut Microbiota Colonization Resistance and Enteric Pathogen Infection. Front Cell Infect Microbiol 2022; 11:716299. [PMID: 35004340 PMCID: PMC8733563 DOI: 10.3389/fcimb.2021.716299] [Citation(s) in RCA: 75] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 11/26/2021] [Indexed: 12/26/2022] Open
Abstract
The mammalian gut microbial community, known as the gut microbiota, comprises trillions of bacteria, which co-evolved with the host and has an important role in a variety of host functions that include nutrient acquisition, metabolism, and immunity development, and more importantly, it plays a critical role in the protection of the host from enteric infections associated with exogenous pathogens or indigenous pathobiont outgrowth that may result from healthy gut microbial community disruption. Microbiota evolves complex mechanisms to restrain pathogen growth, which included nutrient competition, competitive metabolic interactions, niche exclusion, and induction of host immune response, which are collectively termed colonization resistance. On the other hand, pathogens have also developed counterstrategies to expand their population and enhance their virulence to cope with the gut microbiota colonization resistance and cause infection. This review summarizes the available literature on the complex relationship occurring between the intestinal microbiota and enteric pathogens, describing how the gut microbiota can mediate colonization resistance against bacterial enteric infections and how bacterial enteropathogens can overcome this resistance as well as how the understanding of this complex interaction can inform future therapies against infectious diseases.
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Affiliation(s)
- Israr Khan
- School of Life Sciences, Lanzhou University, Lanzhou, China.,Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, Lanzhou University, Lanzhou, China.,Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, Lanzhou University, Lanzhou, China.,Gansu Key Laboratory of Functional Genomics and Molecular Diagnosis, Lanzhou University, Lanzhou, China.,Cuiying Biomedical Research Centre, Lanzhou University Second Hospital, Lanzhou, China
| | - Yanrui Bai
- School of Life Sciences, Lanzhou University, Lanzhou, China.,Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, Lanzhou University, Lanzhou, China.,Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, Lanzhou University, Lanzhou, China.,Gansu Key Laboratory of Functional Genomics and Molecular Diagnosis, Lanzhou University, Lanzhou, China.,Cuiying Biomedical Research Centre, Lanzhou University Second Hospital, Lanzhou, China
| | - Lajia Zha
- School of Life Sciences, Lanzhou University, Lanzhou, China.,Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, Lanzhou University, Lanzhou, China.,Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, Lanzhou University, Lanzhou, China.,Gansu Key Laboratory of Functional Genomics and Molecular Diagnosis, Lanzhou University, Lanzhou, China.,Cuiying Biomedical Research Centre, Lanzhou University Second Hospital, Lanzhou, China
| | - Naeem Ullah
- School of Life Sciences, Lanzhou University, Lanzhou, China.,Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, Lanzhou University, Lanzhou, China.,Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, Lanzhou University, Lanzhou, China
| | - Habib Ullah
- School of Life Sciences, Lanzhou University, Lanzhou, China.,Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, Lanzhou University, Lanzhou, China.,Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, Lanzhou University, Lanzhou, China.,Cuiying Biomedical Research Centre, Lanzhou University Second Hospital, Lanzhou, China
| | - Syed Rafiq Hussain Shah
- Department of Microecology, School of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Hui Sun
- Cuiying Biomedical Research Centre, Lanzhou University Second Hospital, Lanzhou, China
| | - Chunjiang Zhang
- School of Life Sciences, Lanzhou University, Lanzhou, China.,Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, Lanzhou University, Lanzhou, China.,Gansu Key Laboratory of Biomonitoring and Bioremediation for Environmental Pollution, Lanzhou University, Lanzhou, China.,Gansu Key Laboratory of Functional Genomics and Molecular Diagnosis, Lanzhou University, Lanzhou, China
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2
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Olejniczak-Staruch I, Ciążyńska M, Sobolewska-Sztychny D, Narbutt J, Skibińska M, Lesiak A. Alterations of the Skin and Gut Microbiome in Psoriasis and Psoriatic Arthritis. Int J Mol Sci 2021; 22:ijms22083998. [PMID: 33924414 PMCID: PMC8069836 DOI: 10.3390/ijms22083998] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 04/05/2021] [Accepted: 04/06/2021] [Indexed: 12/12/2022] Open
Abstract
Numerous scientific studies in recent years have shown significant skin and gut dysbiosis among patients with psoriasis. A significant decrease in microbiome alpha-diversity (abundance of different bacterial taxa measured in one sample) as well as beta-diversity (microbial diversity in different samples) was noted in psoriasis skin. It has been proven that the representation of Cutibacterium, Burkholderia spp., and Lactobacilli is decreased and Corynebacterium kroppenstedii, Corynebacterium simulans, Neisseria spp., and Finegoldia spp. increased in the psoriasis skin in comparison to healthy skin. Alterations in the gut microbiome in psoriasis are similar to those observed in patients with inflammatory bowel disease. In those two diseases, the F. prausnitzii, Bifidobacterium spp., Lactobacillus spp., Parabacteroides and Coprobacillus were underrepresented, while the abundance of Salmonella sp., Campylobacter sp., Helicobacter sp., Escherichia coli, Alcaligenes sp., and Mycobacterium sp. was increased. Several research studies provided evidence for the significant influence of psoriasis treatments on the skin and gut microbiome and a positive influence of orally administered probiotics on the course of this dermatosis. Further research is needed to determine the influence of the microbiome on the development of inflammatory skin diseases. The changes in microbiome under psoriasis treatment can serve as a potential biomarker of positive response to the administered therapy.
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Affiliation(s)
- Irmina Olejniczak-Staruch
- Department of Dermatology, Pediatric Dermatology and Dermatological Oncology, Medical University of Lodz, 91-347 Lodz, Poland; (D.S.-S.); (J.N.); (M.S.); (A.L.)
- Dermoklinika Centrum Medyczne, 90-436 Lodz, Poland
- Correspondence: ; Tel.: +48-42-230-9657
| | - Magdalena Ciążyńska
- Department of Proliferative Diseases, Nicolaus Copernicus Multidisciplinary Centre for Oncology and Traumatology, 93-513 Lodz, Poland;
| | - Dorota Sobolewska-Sztychny
- Department of Dermatology, Pediatric Dermatology and Dermatological Oncology, Medical University of Lodz, 91-347 Lodz, Poland; (D.S.-S.); (J.N.); (M.S.); (A.L.)
| | - Joanna Narbutt
- Department of Dermatology, Pediatric Dermatology and Dermatological Oncology, Medical University of Lodz, 91-347 Lodz, Poland; (D.S.-S.); (J.N.); (M.S.); (A.L.)
| | - Małgorzata Skibińska
- Department of Dermatology, Pediatric Dermatology and Dermatological Oncology, Medical University of Lodz, 91-347 Lodz, Poland; (D.S.-S.); (J.N.); (M.S.); (A.L.)
| | - Aleksandra Lesiak
- Department of Dermatology, Pediatric Dermatology and Dermatological Oncology, Medical University of Lodz, 91-347 Lodz, Poland; (D.S.-S.); (J.N.); (M.S.); (A.L.)
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The Role of Enterobacteriaceae in Gut Microbiota Dysbiosis in Inflammatory Bowel Diseases. Microorganisms 2021; 9:microorganisms9040697. [PMID: 33801755 PMCID: PMC8066304 DOI: 10.3390/microorganisms9040697] [Citation(s) in RCA: 127] [Impact Index Per Article: 42.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 03/19/2021] [Accepted: 03/23/2021] [Indexed: 12/12/2022] Open
Abstract
Inflammatory bowel diseases (IBDs) are a group of chronic gastrointestinal inflammatory diseases with unknown etiology. There is a combination of well documented factors in their pathogenesis, including intestinal microbiota dysbiosis. The symbiotic microbiota plays important functions in the host, and the loss of beneficial microbes could favor the expansion of microbial pathobionts. In particular, the bloom of potentially harmful Proteobacteria, especially Enterobacteriaceae, has been described as enhancing the inflammatory response, as observed in IBDs. Herein, we seek to investigate the contribution of Enterobacteriaceae to IBD pathogenesis whilst considering the continuous expansion of the literature and data. Despite the mechanism of their expansion still remaining unclear, their expansion could be correlated with the increase in nitrate and oxygen levels in the inflamed gut and with the bile acid dysmetabolism described in IBD patients. Furthermore, in several Enterobacteriaceae studies conducted at a species level, it has been suggested that some adherent-invasive Escherichia coli (AIEC) play an important role in IBD pathogenesis. Overall, this review highlights the pivotal role played by Enterobacteriaceae in gut dysbiosis associated with IBD pathogenesis and progression.
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Naïli I, Gardette M, Garrivier A, Daniel J, Desvaux M, Pizza M, Gobert A, Marchal T, Loukiadis E, Jubelin G. Interplay between enterohaemorrhagic Escherichia coli and nitric oxide during the infectious process. Emerg Microbes Infect 2021; 9:1065-1076. [PMID: 32459575 PMCID: PMC7336997 DOI: 10.1080/22221751.2020.1768804] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Enterohaemorrhagic Escherichia coli (EHEC) are bacterial pathogens responsible for life-threatening diseases in humans such as bloody diarrhoea and the hemolytic and uremic syndrome. To date, no specific therapy is available and treatments remain essentially symptomatic. In recent years, we demonstrated in vitro that nitric oxide (NO), a major mediator of the intestinal immune response, strongly represses the synthesis of the two cardinal virulence factors in EHEC, namely Shiga toxins (Stx) and the type III secretion system, suggesting NO has a great potential to protect against EHEC infection. In this study, we investigated the interplay between NO and EHEC in vivo using mouse models of infection. Using a NO-sensing reporter strain, we determined that EHEC sense NO in the gut of infected mice. Treatment of infected mice with a specific NOS inhibitor increased EHEC adhesion to the colonic mucosa but unexpectedly decreased Stx activity in the gastrointestinal tract, protecting mice from renal failure. Taken together, our data indicate that NO can have both beneficial and detrimental consequences on the outcome of an EHEC infection, and underline the importance of in vivo studies to increase our knowledge in host–pathogen interactions.
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Affiliation(s)
- Ilham Naïli
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France.,GSK, Siena, Italy
| | - Marion Gardette
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France.,Université de Lyon, CNRS, INRAE, Université Claude Bernard Lyon 1, VetAgro Sup, Laboratoire d'Ecologie Microbienne, F-63280 Marcy l'Etoile, France
| | - Annie Garrivier
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
| | - Julien Daniel
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
| | - Mickaël Desvaux
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
| | | | - Alain Gobert
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
| | - Thierry Marchal
- VetAgro Sup, Laboratoire vétérinaire d'histopathologie, F-63280 Marcy-l'Etoile, France
| | - Estelle Loukiadis
- Université de Lyon, CNRS, INRAE, Université Claude Bernard Lyon 1, VetAgro Sup, Laboratoire d'Ecologie Microbienne, F-63280 Marcy l'Etoile, France.,VetAgro Sup, Laboratoire national de référence des E. coli, F-63280 Marcy-l'Etoile, France
| | - Grégory Jubelin
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
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Zhong Q, Kobe B, Kappler U. Molybdenum Enzymes and How They Support Virulence in Pathogenic Bacteria. Front Microbiol 2020; 11:615860. [PMID: 33362753 PMCID: PMC7759655 DOI: 10.3389/fmicb.2020.615860] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 11/23/2020] [Indexed: 12/11/2022] Open
Abstract
Mononuclear molybdoenzymes are highly versatile catalysts that occur in organisms in all domains of life, where they mediate essential cellular functions such as energy generation and detoxification reactions. Molybdoenzymes are particularly abundant in bacteria, where over 50 distinct types of enzymes have been identified to date. In bacterial pathogens, all aspects of molybdoenzyme biology such as molybdate uptake, cofactor biosynthesis, and function of the enzymes themselves, have been shown to affect fitness in the host as well as virulence. Although current studies are mostly focused on a few key pathogens such as Escherichia coli, Salmonella enterica, Campylobacter jejuni, and Mycobacterium tuberculosis, some common themes for the function and adaptation of the molybdoenzymes to pathogen environmental niches are emerging. Firstly, for many of these enzymes, their role is in supporting bacterial energy generation; and the corresponding pathogen fitness and virulence defects appear to arise from a suboptimally poised metabolic network. Secondly, all substrates converted by virulence-relevant bacterial Mo enzymes belong to classes known to be generated in the host either during inflammation or as part of the host signaling network, with some enzyme groups showing adaptation to the increased conversion of such substrates. Lastly, a specific adaptation to bacterial in-host survival is an emerging link between the regulation of molybdoenzyme expression in bacterial pathogens and the presence of immune system-generated reactive oxygen species. The prevalence of molybdoenzymes in key bacterial pathogens including ESKAPE pathogens, paired with the mounting evidence of their central roles in bacterial fitness during infection, suggest that they could be important future drug targets.
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Affiliation(s)
- Qifeng Zhong
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, QLD, Australia
| | - Bostjan Kobe
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, QLD, Australia.,Institute for Molecular Bioscience, The University of Queensland, St. Lucia, QLD, Australia
| | - Ulrike Kappler
- Australian Infectious Diseases Research Centre, School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, QLD, Australia
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Yegorov S, Babenko D, Kozhakhmetov S, Akhmaltdinova L, Kadyrova I, Nurgozhina A, Nurgaziyev M, Good SV, Hortelano GH, Yermekbayeva B, Kushugulova A. Psoriasis Is Associated With Elevated Gut IL-1α and Intestinal Microbiome Alterations. Front Immunol 2020; 11:571319. [PMID: 33117362 PMCID: PMC7559734 DOI: 10.3389/fimmu.2020.571319] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 09/02/2020] [Indexed: 12/20/2022] Open
Abstract
Background Psoriasis is a chronic inflammatory condition that predominantly affects the skin and is associated with extracutaneous disorders, such as inflammatory bowel disease and arthritis. Changes in gut immunology and microbiota are important drivers of proinflammatory disorders and could play a role in the pathogenesis of psoriasis. Therefore, we explored whether psoriasis in a Central Asian cohort is associated with alterations in select immunological markers and/or microbiota of the gut. Methods We undertook a case-control study of stool samples collected from outpatients, aged 30-45 years, of a dermatology clinic in Kazakhstan presenting with plaque, guttate, or palmoplantar psoriasis (n = 20), and age-sex matched subjects without psoriasis (n = 20). Stool supernatant was subjected to multiplex ELISA to assess the concentration of 47 cytokines and immunoglobulins and to 16S rRNA gene sequencing to characterize microbial diversity in both psoriasis participants and controls. Results The psoriasis group tended to have higher concentrations of most analytes in stool (29/47 = 61.7%) and gut IL-1α was significantly elevated (4.19-fold, p = 0.007) compared to controls. Levels of gut IL-1α in the psoriasis participants remained significantly unaltered up to 3 months after the first sampling (p = 0.430). Psoriasis was associated with alterations in gut Firmicutes, including elevated Faecalibacterium and decreased Oscillibacter and Roseburia abundance, but no association was observed between gut microbial diversity or Firmicutes/Bacteroidetes ratios and disease status. Conclusions Psoriasis may be associated with gut inflammation and dysbiosis. Studies are warranted to explore the use of gut microbiome-focused therapies in the management of psoriasis in this under-studied population.
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Affiliation(s)
- Sergey Yegorov
- School of Sciences and Humanities, Nazarbayev University, Nur-Sultan, Kazakhstan.,Faculty of Education and Humanities, Suleyman Demirel University, Almaty, Kazakhstan
| | - Dmitriy Babenko
- Karaganda Medical University Research Centre, Karaganda, Kazakhstan.,Art Science LLP Innovative Center, Nur-Sultan, Kazakhstan
| | - Samat Kozhakhmetov
- Laboratory of Human Microbiome and Longevity, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | | | - Irina Kadyrova
- Karaganda Medical University Research Centre, Karaganda, Kazakhstan
| | - Ayaulym Nurgozhina
- Laboratory of Human Microbiome and Longevity, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - Madiyar Nurgaziyev
- Laboratory of Human Microbiome and Longevity, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - Sara V Good
- Department of Biology, The University of Winnipeg, Winnipeg, MB, Canada
| | - Gonzalo H Hortelano
- School of Sciences and Humanities, Nazarbayev University, Nur-Sultan, Kazakhstan
| | | | - Almagul Kushugulova
- Laboratory of Human Microbiome and Longevity, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
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In vitro spleen cell cytokine responses of adult mice immunized with a recombinant PorA (major outer membrane protein [MOMP]) from Campylobacter jejuni. Sci Rep 2019; 9:12024. [PMID: 31427597 PMCID: PMC6700113 DOI: 10.1038/s41598-019-48249-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 08/01/2019] [Indexed: 11/08/2022] Open
Abstract
There is no information on cytokine profiles for use as markers of protection in Campylobacter jejuni infection. To study this, we used outer membrane protein (MOMP [PorA]) as the vaccine for protection and spleen cell cytokines as markers of protection. We cloned and expressed porA from C. jejuni111 and immunized mice by the intraperitoneal route. Subsequently, mice were orally challenged with live C. jejuni 111. The vaccine induced protection as evidenced by reduced fecal excretion of C. jejuni111. Cytokines were measured in vitro after stimulation of spleen cells with MOMP. The levels of pro-inflammatory cytokines, IL-12, TNF-α, IL-17A and IL-17F were similar in control and test mice. The levels of pro-inflammatory cytokines, IL-2 and IFN-γ were higher in control mice than in test mice, and the levels of pro-inflammatory cytokines, IL-8 and IL-1β were higher in test mice than in control mice. Among the two anti-inflammatory cytokines, the levels were similar for IL-10 but higher for IL-4 in test mice than in control mice. Ratios of pro-inflammatory to anti-inflammatory cytokines showed a bias towards an anti-inflammatory response in favor of antibody production reflecting the role of antibodies in immunity. Cytokine production patterns by spleen cells may be used as markers of protection in the mouse model.
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Wheeler NE, Blackmore T, Reynolds AD, Midwinter AC, Marshall J, French NP, Savoian MS, Gardner PP, Biggs PJ. Genomic correlates of extraintestinal infection are linked with changes in cell morphology in Campylobacter jejuni. Microb Genom 2019; 5:e000251. [PMID: 30777818 PMCID: PMC6421344 DOI: 10.1099/mgen.0.000251] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 12/16/2018] [Indexed: 12/12/2022] Open
Abstract
Campylobacter jejuni is the most common cause of bacterial diarrheal disease in the world. Clinical outcomes of infection can range from asymptomatic infection to life-threatening extraintestinal infections. This variability in outcomes for infected patients has raised questions as to whether genetic differences between C. jejuni isolates contribute to their likelihood of causing severe disease. In this study, we compare the genomes of ten C. jejuni isolates that were implicated in extraintestinal infections with reference gastrointestinal isolates, in order to identify unusual patterns of sequence variation associated with infection outcome. We identified a collection of genes that display a higher burden of uncommon mutations in invasive isolates compared with gastrointestinal close relatives, including some that have been previously linked to virulence and invasiveness in C. jejuni. Among the top genes identified were mreB and pgp1, which are both involved in determining cell shape. Electron microscopy confirmed morphological differences in isolates carrying unusual sequence variants of these genes, indicating a possible relationship between extraintestinal infection and changes in cell morphology.
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Affiliation(s)
- Nicole E. Wheeler
- Center for Genomic Pathogen Surveillance, Wellcome Sanger Institute, Hinxton, UK
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- Biomolecular Interaction Centre, University of Canterbury, Christchurch, New Zealand
| | | | - Angela D. Reynolds
- EpiLab, School of Veterinary Science, Massey University, Palmerston North, New Zealand
| | - Anne C. Midwinter
- EpiLab, School of Veterinary Science, Massey University, Palmerston North, New Zealand
| | - Jonathan Marshall
- EpiLab, School of Veterinary Science, Massey University, Palmerston North, New Zealand
| | - Nigel P. French
- EpiLab, School of Veterinary Science, Massey University, Palmerston North, New Zealand
- New Zealand Food Safety Science and Research Centre, Palmerston North, New Zealand
| | - Matthew S. Savoian
- Institute of Fundamental Sciences, Massey University, Palmerston North, New Zealand
| | - Paul P. Gardner
- School of Biological Sciences, University of Canterbury, Christchurch, New Zealand
- Biomolecular Interaction Centre, University of Canterbury, Christchurch, New Zealand
- Department of Biochemistry, University of Otago, Dunedin, New Zealand.
| | - Patrick J. Biggs
- EpiLab, School of Veterinary Science, Massey University, Palmerston North, New Zealand
- New Zealand Genomics Ltd (NZGL – as Massey Genome Service) Massey University, Palmerston North, New Zealand
- Allan Wilson Centre for Molecular Ecology and Evolution, Massey University, Palmerston North, New Zealand
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9
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A peculiar case of Campylobacter jejuni attenuated aspartate chemosensory mutant, able to cause pathology and inflammation in avian and murine model animals. Sci Rep 2018; 8:12594. [PMID: 30135522 PMCID: PMC6105663 DOI: 10.1038/s41598-018-30604-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 08/01/2018] [Indexed: 01/25/2023] Open
Abstract
An attenuated Campylobacter jejuni aspartate chemoreceptor ccaA mutant caused gross pathological changes despite reduced colonisation ability in animal models. In chickens, the pathological changes included connective tissue and thickening of the mesenteric fat, as well as the disintegration of the villus tips in the large intestine, whereas in mice, hepatomegaly occurred between 48–72 hours post infection and persisted for the six days of the time course. In addition, there was a significant change in the levels of IL-12p70 in mice infected with the C. jejuni ccaA mutant. CcaA isogenic mutant was hyper-invasive in cell culture and microscopic examination revealed that it had a “run” bias in its “run-and-tumble” chemotactic behaviour. The mutant cells also exhibited lower level of binding to fucosylated and higher binding to sialylated glycan structures in glycan array analysis. This study highlights the importance of investigating phenotypic changes in C. jejuni, as we have shown that specific mutants can cause pathological changes in the host, despite reduction in colonisation potential.
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10
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Al-Banna NA, Cyprian F, Albert MJ. Cytokine responses in campylobacteriosis: Linking pathogenesis to immunity. Cytokine Growth Factor Rev 2018; 41:75-87. [PMID: 29550265 DOI: 10.1016/j.cytogfr.2018.03.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 03/08/2018] [Indexed: 12/15/2022]
Abstract
Campylobacter jejuni is an important enteric pathogen that causes diarrheas of different degrees of severity and several extra-intestinal manifestations, including Guillain-Barre syndrome. The variability of disease outcomes is thought to be linked to the immune response induced by C. jejuni. The virulence factors of C. jejuni induce a pro-inflammatory response, that is initiated by the intestinal epithelial cells, propagated by innate immune cells and modulated by the cells of the adaptive immune response. This review focuses on cytokines, that are reported to orchestrate the induction and propagation of pro-inflammatory immune response, and also those that are involved in control and resolution of inflammation. We describe the functional roles of a number of cytokines in modulating anti-Campylobacter immune responses: 1. cytokines of innate immunity (TNF-α, IL-6, and IL-8) as initiators of inflammatory response, 2. cytokines of antigen-presenting cells (IL-1β, IL-12, and IL-23) as promoters of pro-inflammatory response, 3. cytokines produced by T cells (IFN-γ, IL-17, IL-22) as activators of T cells, and 4. anti-inflammatory cytokines (IL-4 and IL-10) as inhibitors of pro-inflammatory responses. We highlight the roles of cytokines as potential therapeutic agents that are under investigation. In the end, we pose several questions that remain unanswered in our quest to understand Campylobacter immunity.
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Affiliation(s)
- Nadia A Al-Banna
- Department of Basic Medical Sciences, College of Medicine, QU Health Cluster, Qatar University, Doha, Qatar.
| | - Farhan Cyprian
- Department of Basic Medical Sciences, College of Medicine, QU Health Cluster, Qatar University, Doha, Qatar.
| | - M John Albert
- Department of Microbiology, Faculty of Medicine, Kuwait University, Jabriya, Kuwait.
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11
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Bäumler AJ, Sperandio V. Interactions between the microbiota and pathogenic bacteria in the gut. Nature 2016; 535:85-93. [PMID: 27383983 PMCID: PMC5114849 DOI: 10.1038/nature18849] [Citation(s) in RCA: 832] [Impact Index Per Article: 104.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 04/22/2016] [Indexed: 02/07/2023]
Abstract
The microbiome has an important role in human health. Changes in the microbiota can confer resistance to or promote infection by pathogenic bacteria. Antibiotics have a profound impact on the microbiota that alters the nutritional landscape of the gut and can lead to the expansion of pathogenic populations. Pathogenic bacteria exploit microbiota-derived sources of carbon and nitrogen as nutrients and regulatory signals to promote their own growth and virulence. By eliciting inflammation, these bacteria alter the intestinal environment and use unique systems for respiration and metal acquisition to drive their expansion. Unravelling the interactions between the microbiota, the host and pathogenic bacteria will produce strategies for manipulating the microbiota against infectious diseases.
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Affiliation(s)
- Andreas J Bäumler
- Department of Medical Microbiology and Immunology, University of California, Davis, School of Medicine, Davis, California 95616, USA
| | - Vanessa Sperandio
- Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9048, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038, USA
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12
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Abstract
Gastroenteritis persists as a worldwide problem, responsible for approximately 2 million deaths annually. Traditional diagnostic methods used in the clinical microbiology laboratory include a myriad of tests, such as culture, microscopy, and immunodiagnostics, which can be labor intensive and suffer from long turnaround times and, in some cases, poor sensitivity. [corrected]. This article reviews recent advances in genomic and proteomic technologies that have been applied to the detection and identification of gastrointestinal pathogens. These methods simplify and speed up the detection of pathogenic microorganisms, and their implementation in the clinical microbiology laboratory has potential to revolutionize the diagnosis of gastroenteritis.
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Diagnosis of Clostridium difficile infection: an ongoing conundrum for clinicians and for clinical laboratories. Clin Microbiol Rev 2014; 26:604-30. [PMID: 23824374 DOI: 10.1128/cmr.00016-13] [Citation(s) in RCA: 277] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Clostridium difficile is a formidable nosocomial and community-acquired pathogen, causing clinical presentations ranging from asymptomatic colonization to self-limiting diarrhea to toxic megacolon and fulminant colitis. Since the early 2000s, the incidence of C. difficile disease has increased dramatically, and this is thought to be due to the emergence of new strain types. For many years, the mainstay of C. difficile disease diagnosis was enzyme immunoassays for detection of the C. difficile toxin(s), although it is now generally accepted that these assays lack sensitivity. A number of molecular assays are commercially available for the detection of C. difficile. This review covers the history and biology of C. difficile and provides an in-depth discussion of the laboratory methods used for the diagnosis of C. difficile infection (CDI). In addition, strain typing methods for C. difficile and the evolving epidemiology of colonization and infection with this organism are discussed. Finally, considerations for diagnosing C. difficile disease in special patient populations, such as children, oncology patients, transplant patients, and patients with inflammatory bowel disease, are described. As detection of C. difficile in clinical specimens does not always equate with disease, the diagnosis of C. difficile infection continues to be a challenge for both laboratories and clinicians.
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14
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The dynamics of gut-associated microbial communities during inflammation. EMBO Rep 2013; 14:319-27. [PMID: 23478337 DOI: 10.1038/embor.2013.27] [Citation(s) in RCA: 240] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 02/14/2013] [Indexed: 12/20/2022] Open
Abstract
Our intestine is host to a large microbial community (microbiota) that educates the immune system and confers niche protection. Profiling of the gut-associated microbial community reveals a dominance of obligate anaerobic bacteria in healthy individuals. However, intestinal inflammation is associated with a disturbance of the microbiota-known as dysbiosis-that often includes an increased prevalence of facultative anaerobic bacteria. This group contains potentially harmful bacterial species, the bloom of which can further exacerbate inflammation. Here, we review the mechanisms that generate changes in the microbial community structure during inflammation. One emerging concept is that electron acceptors generated as by-products of the host inflammatory response feed facultative anaerobic bacteria selectively, thereby increasing their prevalence within the community. This new paradigm has broad implications for understanding dysbiosis during gut inflammation and identifies potential targets for intervention strategies.
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Winter SE, Winter MG, Xavier MN, Thiennimitr P, Poon V, Keestra AM, Laughlin RC, Gomez G, Wu J, Lawhon SD, Popova IE, Parikh SJ, Adams LG, Tsolis RM, Stewart VJ, Bäumler AJ. Host-derived nitrate boosts growth of E. coli in the inflamed gut. Science 2013; 339:708-11. [PMID: 23393266 DOI: 10.1126/science.1232467] [Citation(s) in RCA: 660] [Impact Index Per Article: 60.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Changes in the microbial community structure are observed in individuals with intestinal inflammatory disorders. These changes are often characterized by a depletion of obligate anaerobic bacteria, whereas the relative abundance of facultative anaerobic Enterobacteriaceae increases. The mechanisms by which the host response shapes the microbial community structure, however, remain unknown. We show that nitrate generated as a by-product of the inflammatory response conferred a growth advantage to the commensal bacterium Escherichia coli in the large intestine of mice. Mice deficient in inducible nitric oxide synthase did not support the growth of E. coli by nitrate respiration, suggesting that the nitrate generated during inflammation was host-derived. Thus, the inflammatory host response selectively enhances the growth of commensal Enterobacteriaceae by generating electron acceptors for anaerobic respiration.
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Affiliation(s)
- Sebastian E Winter
- Department of Medical Microbiology and Immunology, School of Medicine, University of California, Davis, One Shields Avenue, Davis, CA, USA
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16
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Lee K, Lillehoj H, Jang S, Li G, Bautista D, Phillips K, Ritter D, Lillehoj E, Siragusa G. Effects of coccidiosis control programs on antibody levels against selected pathogens and serum nitric oxide levels in broiler chickens. J APPL POULTRY RES 2011. [DOI: 10.3382/japr.2010-00218] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Mühl H, Bachmann M, Pfeilschifter J. Inducible NO synthase and antibacterial host defence in times of Th17/Th22/T22 immunity. Cell Microbiol 2011; 13:340-8. [PMID: 21199257 DOI: 10.1111/j.1462-5822.2010.01559.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
During the last two decades nitric oxide (NO) produced by inducible NO synthase (iNOS or NOS2) has been characterized as immunoregulatory and antimicrobial principle displaying the potential to determine course of disease in a range of infections. Being an enzyme primarily regulated on expressional level, cytokine-driven iNOS appears to be connected in particular with activation of Th1-type immunity. However, with the recent advent of additional, partly overlapping CD4(+) T cell effector subsets, namely Th17 and Th22 cells, a further layer of complexity has been added to immunoregulatory networks determining inflammatory gene expression in the context of microbial infections. Here, we review current knowledge on activation of iNOS function by interleukin (IL)-17 and IL-22 with focus on Th17/Th22-directed antibacterial immunity.
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Affiliation(s)
- Heiko Mühl
- Pharmazentrum frankfurt/ZAFES, University Hospital Goethe-University, Frankfurt am Main, Germany.
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18
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Redox sensor SsrB Cys203 enhances Salmonella fitness against nitric oxide generated in the host immune response to oral infection. Proc Natl Acad Sci U S A 2010; 107:14396-401. [PMID: 20660761 DOI: 10.1073/pnas.1005299107] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
We show herein that the Salmonella pathogenicity island 2 (SPI2) response regulator SsrB undergoes S-nitrosylation upon exposure of Salmonella to acidified nitrite, a signal encountered by this enteropathogen in phagosomes of macrophages. Mutational analysis has identified Cys(203) in the C-terminal dimerization domain of SsrB as the redox-active residue responding to nitric oxide (NO) congeners generated in the acidification of nitrite. Peroxynitrite and products of the autooxidation of NO in the presence of oxygen, but not hydrogen peroxide, inhibit the DNA-binding capacity of SsrB, demonstrating the selectivity of the reaction of Cys(203) with reactive nitrogen species (RNS). These findings identify the two-component response regulator SsrB Cys(203) as a thiol-based redox sensor. A C203S substitution protects SsrB against the attack of RNS while preserving its DNA-binding capacity. When exposed to SPI2-inducing conditions, Salmonella expressing the wild-type ssrB allele or the ssrB C203S variant sustain transcription of the sifA, sspH2, and srfJ effector genes. Nonetheless, compared with the strain expressing a redox-resistant SsrB C203S variant, wild-type Salmonella bearing the NO-responsive allele exhibit increased fitness when exposed to RNS in an NRAMP(R), C3H/HeN murine model of acute oral infection. Given the widespread occurrence of the wild-type allele in Salmonella enterica, these findings indicate that SsrB Cys(203) increases Salmonella virulence by serving as a redox sensor of NO resulting from the host immune response to oral infection.
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Correlation of proinflammatory and anti-inflammatory cytokine levels with histopathological changes in an adult mouse lung model of Campylobacter jejuni infection. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2008; 15:1780-7. [PMID: 18827187 DOI: 10.1128/cvi.00193-08] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Campylobacter jejuni is a major cause of diarrhea in humans. A mouse lung model of infection was previously established for C. jejuni. We used this model to study cytokine production in the lungs and correlated it with pathological changes. C. jejuni strain 81-176 or sterile phosphate-buffered saline was intranasally inoculated into adult BALB/c mice. The levels of proinflammatory cytokines (gamma interferon, tumor necrosis factor alpha, interleukin-1beta [IL-1beta], IL-2) and anti-inflammatory cytokines (IL-4, IL-10), in addition to those of IL-6, were assessed on days 1, 3, and 5 postinfection by enzyme-linked immunosorbent assay, and the ratios of proinflammatory cytokines to anti-inflammatory cytokines were calculated. Since IL-6 is unique in that it is both a proinflammatory cytokine and a TH2 cytokine, it was considered to be both in the determination of these ratios. The significance of the cytokine levels and ratios were determined by the Mann-Whitney U test (P<or=0.05). The induction of proinflammatory cytokines in the lungs of infected mice, as indicated by the cytokine levels and ratios, coincided with the accumulation of neutrophils and activated macrophages, in addition to the clearance of the bacterial load and bacteriumlike structures that we have previously shown in the same groups of mice. This was followed by increased levels of anti-inflammatory cytokines and the resolution of inflammation and pathology in the lungs. This study demonstrates the dynamics of cytokine production and their correlation with tissue inflammation and the resolution of infection. This model is useful for further studies of the pathogenesis of C. jejuni infection and vaccine evaluation.
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Li YP, Ingmer H, Madsen M, Bang DD. Cytokine responses in primary chicken embryo intestinal cells infected with Campylobacter jejuni strains of human and chicken origin and the expression of bacterial virulence-associated genes. BMC Microbiol 2008; 8:107. [PMID: 18588667 PMCID: PMC2443369 DOI: 10.1186/1471-2180-8-107] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2007] [Accepted: 06/27/2008] [Indexed: 02/01/2023] Open
Abstract
Background Campylobacter jejuni is a major cause of inflammatory diarrhoea in humans and is considered a commensal of the gastroenteric tract of the avian host. However, little is known about the interaction between C. jejuni and the avian host including the cytokine responses and the expression of the bacterial genes. We have investigated the invasiveness of primary chicken embryo intestinal cells (CEICs) by C. jejuni strains of human and chicken origins and the production of pro-inflammatory cytokines as well as the expression of the bacterial virulence-associated genes during co-cultivation. Results C. jejuni strains are capable of invading the CEICs and stimulate these cells in a pro-inflammatory manner and during this interaction the expression of the bacterial virulence-associated genes ciaB, dnaJ and racR is increased. Furthermore, incubation of bacteria with conditioned cell- and bacteria-free media from another co-cultivation experiment also increased the expression of the virulence-associated genes in the C. jejuni chicken isolate, indicating that the expression of bacterial genes is regulated by component(s) secreted upon co-cultivation of bacteria and CEICs. Conclusion We show that under in vitro culture condition C. jejuni strains of both human and chicken origins can invade avian host cells with a pro-inflammatory response and that the virulence-associated genes of C. jejuni may play a role in this process.
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Affiliation(s)
- Yi-Ping Li
- Department of Poultry, Fish and Fur Animals, National Veterinary Institute (VET), Technical University of Denmark (DTU), Hangøvej 2, DK-8200 Aarhus N, Denmark.
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21
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Expression and purification of Cgb and Ctb, the NO-inducible globins of the foodborne bacterial pathogen C. jejuni. Methods Enzymol 2008. [PMID: 18237639 DOI: 10.1016/s0076-6879(08)36016-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Campylobacter jejuni is a Gram-negative microaerophilic bacterium that occurs as a common gut commensal in many food-producing animals and birds. Contamination of meat during processing is an important route of transmission, and C. jejuni is now recognized as one of the most important causes of bacterial gastroenteritis worldwide. C. jejuni is notable, but not unique, in possessing two different hemoglobins. The first is termed Cgb and is a single-domain hemoglobin (i.e., having no other protein domain or cofactor) with clear structural similarities (3/3) with myoglobin, the heme domain of flavohemoglobins and Vitreoscilla hemoglobin. It is well established that Cgb plays a key role in providing resistance to C. jejuni in the face of NO and other reactive nitrogen species that might be encountered in its environments. The second globin is Ctb, a truncated globin (2/2trHb) in class III, until recently the least well-understood class of these ubiquitous globins. In C. jejuni, both globin genes are members of a small regulon activated by the NssR protein, which acts as an NO sensor and transcriptional regulator. In this contribution, we describe the cloning of both the cgb and ctb genes from C. jejuni chromosomal DNA, construction of expression vectors in E. coli, and a simple purification procedure for each globin. A brief account of the spectroscopic characteristics of both globins is presented.
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22
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Anand RJ, Dai S, Rippel C, Leaphart C, Qureshi F, Gribar SC, Kohler JW, Li J, Stolz DB, Sodhi C, Hackam DJ. Activated macrophages inhibit enterocyte gap junctions via the release of nitric oxide. Am J Physiol Gastrointest Liver Physiol 2008; 294:G109-19. [PMID: 17975131 DOI: 10.1152/ajpgi.00331.2007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Enterocytes exist in close association with tissue macrophages, whose activation during inflammatory processes leads to the release of nitric oxide (NO). Repair from mucosal injury requires the migration of enterocytes into the mucosal defect, a process that requires connexin43 (Cx43)-mediated gap junction communication between adjacent enterocytes. Enterocyte migration is inhibited during inflammatory conditions including necrotizing enterocolitis, in part, through impaired gap junction communication. We now hypothesize that activated macrophages inhibit gap junctions of adjacent enterocytes and seek to determine whether NO release from macrophages was involved. Using a coculture system of enterocytes and macrophages, we now demonstrate that "activation" of macrophages with lipopolysaccharide and interferon reduces the phosphorylation of Cx43 in adjacent enterocytes, an event known to inhibit gap junction communication. The effects of macrophages on enterocyte gap junctions could be reversed by treatment of macrophages with the inducible nitric oxide synthase (iNOS) inhibitor l-Lysine omega-acetamidine hydrochloride (l-NIL) and by incubation with macrophages from iNOS(-/-) mice, implicating NO in the process. Activated macrophages also caused a NO-dependent redistribution of connexin43 in adjacent enterocytes from the cell surface to an intracellular location, further suggesting NO release may inhibit gap junction function. Treatment of enterocytes with the NO donor S-nitroso-N-acetylpenicillamine (SNAP) markedly inhibited gap junction communication as determined using single cell microinjection of the gap junction tracer Lucifer yellow. Strikingly, activated macrophages inhibited enterocyte migration into a scraped wound, which was reversed by l-NIL pretreatment. These results implicate enterocyte gap junctions as a target of the NO-mediated effects of macrophages during intestinal inflammation, particularly where enterocyte migration is impaired.
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Affiliation(s)
- Rahul J Anand
- Department of Surgery, Children's Hospital of Pittsburgh, Pittsburgh, PA 15213, USA
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23
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Cetin S, Leaphart CL, Li J, Ischenko I, Hayman M, Upperman J, Zamora R, Watkins S, Ford HR, Wang J, Hackam DJ. Nitric oxide inhibits enterocyte migration through activation of RhoA-GTPase in a SHP-2-dependent manner. Am J Physiol Gastrointest Liver Physiol 2007; 292:G1347-58. [PMID: 17272518 DOI: 10.1152/ajpgi.00375.2006] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Diseases of intestinal inflammation like necrotizing enterocolitis (NEC) are associated with impaired epithelial barrier integrity and the sustained release of intestinal nitric oxide (NO). NO modifies the cytoskeletal regulator RhoA-GTPase, suggesting that NO could affect barrier healing by inhibiting intestinal restitution. We now hypothesize that NO inhibits enterocyte migration through RhoA-GTPase and sought to determine the pathways involved. The induction of NEC was associated with increased enterocyte NO release and impaired migration of bromodeoxyuridine-labeled enterocytes from terminal ileal crypts to villus tips. In IEC-6 enterocytes, NO significantly inhibited enterocyte migration and activated RhoA-GTPase while increasing the formation of stress fibers. In parallel, exposure of IEC-6 cells to NO increased the phosphorylation of focal adhesion kinase (pFAK) and caused a striking increase in cell-matrix adhesiveness, suggesting a mechanism by which NO could impair enterocyte migration. NEC was associated with increased expression of pFAK in the terminal ileal mucosa of wild-type mice and a corresponding increase in disease severity compared with inducible NO synthase knockout mice, confirming the dependence of NO for FAK phosphorylation in vivo and its role in the pathogenesis of NEC. Strikingly, inhibition of the protein tyrosine phosphatase SHP-2 in IEC-6 cells prevented the activation of RhoA by NO, restored focal adhesions, and reversed the inhibitory effects of NO on enterocyte migration. These data indicate that NO impairs mucosal healing by inhibiting enterocyte migration through activation of RhoA in a SHP-2-dependent manner and support a possible role for SHP-2 as a therapeutic target in diseases of intestinal inflammation like NEC.
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Affiliation(s)
- Selma Cetin
- Div. of Pediatric Surgery, Department of Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA
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24
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Pittman MS, Elvers KT, Lee L, Jones MA, Poole RK, Park SF, Kelly DJ. Growth ofCampylobacter jejunion nitrate and nitrite: electron transport to NapA and NrfA via NrfH and distinct roles for NrfA and the globin Cgb in protection against nitrosative stress. Mol Microbiol 2006; 63:575-90. [PMID: 17241202 DOI: 10.1111/j.1365-2958.2006.05532.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pathways of electron transport to periplasmic nitrate (NapA) and nitrite (NrfA) reductases have been investigated in Campylobacter jejuni, a microaerophilic food-borne pathogen. The nap operon is unusual in lacking napC (encoding a tetra-haem c-type cytochrome) and napF, but contains a novel gene of unknown function, napL. The iron-sulphur protein NapG has a major role in electron transfer to the NapAB complex, but we show that slow nitrate-dependent growth of a napG mutant can be sustained by electron transfer from NrfH, the electron donor to the nitrite reductase NrfA. A napL mutant possessed approximately 50% lower NapA activity than the wild type but showed normal growth with nitrate as the electron acceptor. NrfA was constitutive and was shown to play a role in protection against nitrosative stress in addition to the previously identified NO-inducible single domain globin, Cgb. However, nitrite also induced cgb expression in an NssR-dependent manner, suggesting that growth of C. jejuni with nitrite causes nitrosative stress. This was confirmed by lack of growth of cgb and nssR mutants, and slow growth of the nrfA mutant, in media containing nitrite. Thus, NrfA and Cgb together provide C. jejuni with constitutive and inducible components of a robust defence against nitrosative stress.
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Affiliation(s)
- Marc S Pittman
- Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
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25
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Maresca M, Miller D, Quitard S, Dean P, Kenny B. Enteropathogenic Escherichia coli (EPEC) effector-mediated suppression of antimicrobial nitric oxide production in a small intestinal epithelial model system. Cell Microbiol 2006; 7:1749-62. [PMID: 16309461 DOI: 10.1111/j.1462-5822.2005.00587.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In vivo studies with the mouse-specific member of the attaching and effacing (A/E) family of pathogens raised the possibility that these non-invasive enteric pathogens can specifically inhibit inducible nitric oxide synthase (iNOS) expression to prevent the production of antimicrobial nitric oxide (NO). In this study we use polarized Caco-2 cells, a model of human small intestinal epithelia, to (i) demonstrate conclusively that an A/E member, human specific enteropathogenic Escherichia coli (EPEC), can inhibit cytokine-induced iNOS expression, (ii) show that this activity is dependent on the delivery of effector molecules into host cells and (iii) investigate the mechanism of inhibition. Analysis of the level of iNOS-related mRNA, protein and NO production demonstrated that EPEC can inhibit iNOS expression at the transcriptional, by direct and indirect mechanisms, and post-transcriptional levels. This transcriptional block was linked to the failure of the iNOS-related transcriptional factor NF-kappaB, but not STAT1, to undergo phosphorylation-associated activation. A selective pressure to prevent iNOS production was evidenced by the finding that iNOS activity had a potent antimicrobial effect on adherent but not non-adherent bacteria. Moreover, given the central role NF-kappaB plays in transcribing genes associated with early host immune responses, this inhibitory mechanism presumably represents an important role in pathogenesis. Our study also provides insights into the nature of NO production in response to bacterial infection as well as the role of the locus of enterocyte effacement (LEE)-encoded effector molecules in inhibiting iNOS expression.
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Affiliation(s)
- Marc Maresca
- Institute for Cell and Molecular Biosciences, Medical School, University of Newcastle, Framlington Place, Newcastle upon Tyne, NE24HH, UK
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26
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Lundberg JO, Hellström PM, Fagerhol MK, Weitzberg E, Roseth AG. Technology insight: calprotectin, lactoferrin and nitric oxide as novel markers of inflammatory bowel disease. ACTA ACUST UNITED AC 2005; 2:96-102. [PMID: 16265127 DOI: 10.1038/ncpgasthep0094] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2004] [Accepted: 01/04/2005] [Indexed: 12/22/2022]
Abstract
Distinguishing patients with inflammatory bowel disease from those with irritable bowel syndrome can be difficult. A simple and reliable test that detects intestinal inflammation would therefore be very useful in the clinic. If such a test parameter correlated with the intensity of the inflammatory reaction it could also be used to monitor disease activity. Calprotectin, lactoferrin and nitric oxide are produced and released locally in much greater quantities in the inflamed gut than in the noninflamed gut. These compounds can be readily measured in fecal samples (calprotectin and lactoferrin) or directly in the intestinal lumen (nitric oxide gas). Here, we discuss what is known about these markers, how they could be used in clinical practice and how they can complement existing techniques used for the diagnosis and monitoring of inflammatory bowel disease.
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Affiliation(s)
- Jon O Lundberg
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden.
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27
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Elvers KT, Turner SM, Wainwright LM, Marsden G, Hinds J, Cole JA, Poole RK, Penn CW, Park SF. NssR, a member of the Crp-Fnr superfamily from Campylobacter jejuni, regulates a nitrosative stress-responsive regulon that includes both a single-domain and a truncated haemoglobin. Mol Microbiol 2005; 57:735-50. [PMID: 16045618 DOI: 10.1111/j.1365-2958.2005.04723.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Consistent with its role as a nitric oxide (NO)-detoxifying globin in Campylobacter jejuni, Cgb (Campylobacter globin) expression is strongly and specifically induced following exposure to nitrosative stress, suggesting a previously unrecognized capacity for NO-related stress sensing in this food-borne pathogen. In this study, Fur and PerR have been eliminated as major regulators of cgb, and NssR (Cj0466), a member of the Crp-Fnr superfamily, has been identified as the major positive regulatory factor that controls nitrosative stress-responsive expression of this gene. Accordingly, disruption of nssR resulted in the abolition of inducible cgb expression, which was restored by a complementing chromosomal insertion of the wild-type gene with its indigenous promoter at a second location. The NssR-deficient mutant was more sensitive to NO-related stress than a cgb mutant and this phenotype most likely arises from the failure of these cells to induce other NO-responsive components in addition to Cgb. Indeed, analysis of global gene expression, by microarray and confirmatory real-time polymerase chain reaction (PCR) in the wild type and nssR mutant, not only confirmed the dependence of inducible cgb expression on NssR, but also revealed for the first time a novel NssR-dependent nitrosative stress-responsive regulon. This regulon of at least four genes includes Cj0465c, a truncated globin. Consistent with NssR being a Crp-Fnr superfamily member, an Fnr-like binding sequence (TTAAC-N(4)-GTTAA) was found upstream of each gene at locations -40.5 to -42.5 relative to the centre of the binding sites and the transcription start point. Site-directed mutagenesis confirmed that this cis-acting motif mediates the nitrosative stress-inducible expression of cgb.
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Affiliation(s)
- Karen T Elvers
- School of Biomedical and Molecular Sciences, University of Surrey, Guildford GU2 7XH, UK
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28
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Smith CK, Kaiser P, Rothwell L, Humphrey T, Barrow PA, Jones MA. Campylobacter jejuni-induced cytokine responses in avian cells. Infect Immun 2005; 73:2094-100. [PMID: 15784550 PMCID: PMC1087459 DOI: 10.1128/iai.73.4.2094-2100.2005] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Campylobacter jejuni is a major cause of human inflammatory enteritis. During the course of human disease numerous proinflammatory cytokines are produced. Little is known, however, about the cytokine responses produced during the interaction of this bacterium with the avian host. Campylobacter has been considered a commensal of the avian host. Any differences in innate responses to this pathogen between the human and avian hosts should lead to a greater understanding of the disease process in humans. We have demonstrated expression of proinflammatory cytokines and chemokines in response to Campylobacter infection in avian primary chick kidney cells and the avian macrophage cell line HD11. The data indicate that Campylobacter can stimulate the avian host in a proinflammatory manner. The data strongly suggest that the lack of pathology in vivo is not due to an inability of Campylobacter to stimulate a proinflammatory response from avian cells.
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Affiliation(s)
- Chris K Smith
- Institute for Animal Health, Compton, Berkshire RG20 7NN, United Kingdom
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