51
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Tschurtschenthaler M, Adolph TE, Ashcroft JW, Niederreiter L, Bharti R, Saveljeva S, Bhattacharyya J, Flak MB, Shih DQ, Fuhler GM, Parkes M, Kohno K, Iwawaki T, Janneke van der Woude C, Harding HP, Smith AM, Peppelenbosch MP, Targan SR, Ron D, Rosenstiel P, Blumberg RS, Kaser A. Defective ATG16L1-mediated removal of IRE1α drives Crohn's disease-like ileitis. J Exp Med 2017; 214:401-422. [PMID: 28082357 PMCID: PMC5294857 DOI: 10.1084/jem.20160791] [Citation(s) in RCA: 130] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 10/02/2016] [Accepted: 12/07/2016] [Indexed: 02/02/2023] Open
Abstract
ATG16L1T300A, a major risk polymorphism in Crohn's disease (CD), causes impaired autophagy, but it has remained unclear how this predisposes to CD. In this study, we report that mice with Atg16l1 deletion in intestinal epithelial cells (IECs) spontaneously develop transmural ileitis phenocopying ileal CD in an age-dependent manner, driven by the endoplasmic reticulum (ER) stress sensor IRE1α. IRE1α accumulates in Paneth cells of Atg16l1ΔIEC mice, and humans homozygous for ATG16L1T300A exhibit a corresponding increase of IRE1α in intestinal epithelial crypts. In contrast to a protective role of the IRE1β isoform, hyperactivated IRE1α also drives a similar ileitis developing earlier in life in Atg16l1;Xbp1ΔIEC mice, in which ER stress is induced by deletion of the unfolded protein response transcription factor XBP1. The selective autophagy receptor optineurin interacts with IRE1α, and optineurin deficiency amplifies IRE1α levels during ER stress. Furthermore, although dysbiosis of the ileal microbiota is present in Atg16l1;Xbp1ΔIEC mice as predicted from impaired Paneth cell antimicrobial function, such structural alteration of the microbiota does not trigger ileitis but, rather, aggravates dextran sodium sulfate-induced colitis. Hence, we conclude that defective autophagy in IECs may predispose to CD ileitis via impaired clearance of IRE1α aggregates during ER stress at this site.
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Affiliation(s)
- Markus Tschurtschenthaler
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, England, UK
| | - Timon E. Adolph
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, England, UK
| | - Jonathan W. Ashcroft
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, England, UK
| | - Lukas Niederreiter
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, England, UK
| | - Richa Bharti
- Institute for Clinical Molecular Biology, Christian-Albrechts-University Kiel, D-24105 Kiel, Germany
| | - Svetlana Saveljeva
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, England, UK
| | - Joya Bhattacharyya
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, England, UK
| | - Magdalena B. Flak
- Division of Gastroenterology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115
| | - David Q. Shih
- Inflammatory Bowel and Immunobiology Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048
| | - Gwenny M. Fuhler
- Department of Gastroenterology and Hepatology, Erasmus University Medical Center Rotterdam, 3015 CE Rotterdam, Netherlands
| | - Miles Parkes
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, England, UK
| | - Kenji Kohno
- Laboratory of Molecular and Cell Genetics, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Takao Iwawaki
- Division of Cell Medicine, Department of Life Science, Medical Research Institute, Kanazawa Medical University, Kahoku, Ishikawa 920-0293, Japan
| | - C. Janneke van der Woude
- Department of Gastroenterology and Hepatology, Erasmus University Medical Center Rotterdam, 3015 CE Rotterdam, Netherlands
| | - Heather P. Harding
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0QQ, England, UK
| | - Andrew M. Smith
- Eastman Dental Institute, University College London, London WC1E 6BT, England, UK
| | - Maikel P. Peppelenbosch
- Department of Gastroenterology and Hepatology, Erasmus University Medical Center Rotterdam, 3015 CE Rotterdam, Netherlands
| | - Stephan R. Targan
- Inflammatory Bowel and Immunobiology Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048
| | - David Ron
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0QQ, England, UK
| | - Philip Rosenstiel
- Institute for Clinical Molecular Biology, Christian-Albrechts-University Kiel, D-24105 Kiel, Germany
| | - Richard S. Blumberg
- Division of Gastroenterology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115
| | - Arthur Kaser
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, England, UK
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52
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Friedrich A, Pechstein J, Berens C, Lührmann A. Modulation of host cell apoptotic pathways by intracellular pathogens. Curr Opin Microbiol 2017; 35:88-99. [DOI: 10.1016/j.mib.2017.03.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 12/03/2016] [Accepted: 03/01/2017] [Indexed: 12/13/2022]
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53
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Hernández-Flores KG, Calderón-Garcidueñas AL, Mellado-Sánchez G, Ruiz-Ramos R, Sánchez-Vargas LA, Thomas-Dupont P, Izaguirre-Hernández IY, Téllez-Sosa J, Martínez-Barnetche J, Wood L, Paterson Y, Cedillo-Barrón L, López-Franco O, Vivanco-Cid H. Evaluation of the safety and adjuvant effect of a detoxified listeriolysin O mutant on the humoral response to dengue virus antigens. Clin Exp Immunol 2017; 188:109-126. [PMID: 27886660 DOI: 10.1111/cei.12906] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/08/2016] [Indexed: 01/14/2023] Open
Abstract
Listeriolysin O (LLO) has been proposed as a potential carrier or adjuvant molecule in the vaccination field. However, the cytotoxic and pro-apoptotic effects of LLO are the major limitations for this purpose. Here, we have performed a preclinical safety evaluation and characterized a new potential adjuvant application for a non-cytolytic LLO mutant (dtLLO) to enhance and modulate the immune response against the envelope (E) protein from dengue virus. In addition, we have studied the adjuvant effects of dtLLO on human immune cells and the role of membrane cholesterol for the binding and proinflammatory property of the toxoid. Our in-vivo results in the murine model confirmed that dtLLO is a safer molecule than wild-type LLO (wtLLO), with a significantly increased survival rate for mice challenged with dtLLO compared with mice challenged with wtLLO (P < 0·001). Histopathological analysis showed non-toxic effects in key target organs such as brain, heart, liver, spleen, kidney and lung after challenge with dtLLO. In vitro, dtLLO retained the capacity of binding to plasma membrane cholesterol on the surface of murine and human immune cells. Immunization of 6-8-week-old female BALB/c mice with a combination of dtLLO mixed with E protein elicited a robust specific humoral response with isotype diversification of immunoglobulin (Ig)G antibodies (IgG1 and IgG2a). Finally, we demonstrated that cholesterol and lipid raft integrity are required to induce a proinflammatory response by human cells. Taken together, these findings support a potential use of the dtLLO mutant as a safe and effective adjuvant molecule in vaccination.
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Affiliation(s)
- K G Hernández-Flores
- Instituto de Investigaciones Médico-Biológicas, Universidad Veracruzana, Veracruz City, Veracruz, México.,Doctorado en Ciencias Biomédicas, Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa Veracruz, México
| | | | - G Mellado-Sánchez
- Instituto de Investigaciones Médico-Biológicas, Universidad Veracruzana, Veracruz City, Veracruz, México
| | - R Ruiz-Ramos
- Instituto de Medicina Forense, Universidad Veracruzana, Boca del Río Veracruz, México
| | - L A Sánchez-Vargas
- Instituto de Investigaciones Médico-Biológicas, Universidad Veracruzana, Veracruz City, Veracruz, México.,Doctorado en Ciencias Biomédicas, Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa Veracruz, México
| | - P Thomas-Dupont
- Instituto de Investigaciones Médico-Biológicas, Universidad Veracruzana, Veracruz City, Veracruz, México.,Doctorado en Ciencias Biomédicas, Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa Veracruz, México
| | - I Y Izaguirre-Hernández
- Instituto de Investigaciones Médico-Biológicas, Universidad Veracruzana, Veracruz City, Veracruz, México.,Doctorado en Ciencias Biomédicas, Centro de Investigaciones Biomédicas, Universidad Veracruzana, Xalapa Veracruz, México
| | - J Téllez-Sosa
- Departamento de Inmunología, Instituto Nacional de Salud Pública (INSP), Centro de Investigación Sobre Enfermedades Infecciosas (CISEI), Cuernavaca, México
| | - J Martínez-Barnetche
- Departamento de Inmunología, Instituto Nacional de Salud Pública (INSP), Centro de Investigación Sobre Enfermedades Infecciosas (CISEI), Cuernavaca, México
| | - L Wood
- Department of Microbiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Y Paterson
- Department of Microbiology, University of Pennsylvania, Philadelphia, PA, USA
| | - L Cedillo-Barrón
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados IPN, Ciudad de México, México
| | - O López-Franco
- Centro de Estudios y Servicios en Salud. Universidad Veracruzana, Veracruz City, Veracruz, México
| | - H Vivanco-Cid
- Instituto de Investigaciones Médico-Biológicas, Universidad Veracruzana, Veracruz City, Veracruz, México
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54
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Malet JK, Cossart P, Ribet D. Alteration of epithelial cell lysosomal integrity induced by bacterial cholesterol-dependent cytolysins. Cell Microbiol 2016; 19. [PMID: 27739224 PMCID: PMC5347955 DOI: 10.1111/cmi.12682] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 10/07/2016] [Accepted: 10/07/2016] [Indexed: 12/14/2022]
Abstract
Bacterial pathogens can interfere during infection with host cell organelles, such as mitochondria, the endoplasmic reticulum‐Golgi system or nuclei. As important cellular functions are often compartmentalized in these organelles, their targeting allows pathogens to manipulate key host functions during infection. Here, we identify lysosomes as a new class of organelles targeted by the pathogenic bacterium Listeria monocytogenes. We demonstrate that extracellular Listeria, via secretion of the pore‐forming toxin listeriolysin O, alters lysosomal integrity in epithelial cells but not in macrophages. Listeriolysin O induces lysosomal membrane permeabilization and release of lysosomal content, such as cathepsins proteases, which remain transiently active in the host cytosol. We furthermore show that other bacterial pore‐forming toxins, such as perfringolysin O and pneumolysin, also induce lysosomes alteration. Together, our data unveil a novel activity of bacterial cholesterol‐dependent cytolysins.
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Affiliation(s)
- Julien Karim Malet
- Unité des Interactions Bactéries-Cellules, Institut Pasteur, F-75015, Paris, France.,Inserm, U604, F-75015, Paris, France.,INRA, USC2020, F-75015, Paris, France.,Univ. Paris Diderot, Sorbonne Paris Cité, F-75015, Paris, France
| | - Pascale Cossart
- Unité des Interactions Bactéries-Cellules, Institut Pasteur, F-75015, Paris, France.,Inserm, U604, F-75015, Paris, France.,INRA, USC2020, F-75015, Paris, France
| | - David Ribet
- Unité des Interactions Bactéries-Cellules, Institut Pasteur, F-75015, Paris, France.,Inserm, U604, F-75015, Paris, France.,INRA, USC2020, F-75015, Paris, France
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55
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Moretti J, Blander JM. Cell-autonomous stress responses in innate immunity. J Leukoc Biol 2016; 101:77-86. [PMID: 27733577 DOI: 10.1189/jlb.2mr0416-201r] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 08/10/2016] [Accepted: 08/24/2016] [Indexed: 12/12/2022] Open
Abstract
The innate immune response of phagocytes to microbes has long been known to depend on the core signaling cascades downstream of pattern recognition receptors (PRRs), which lead to expression and production of inflammatory cytokines that counteract infection and induce adaptive immunity. Cell-autonomous responses have recently emerged as important mechanisms of innate immunity. Either IFN-inducible or constitutive, these processes aim to guarantee cell homeostasis but have also been shown to modulate innate immune response to microbes and production of inflammatory cytokines. Among these constitutive cell-autonomous responses, autophagy is prominent and its role in innate immunity has been well characterized. Other stress responses, such as metabolic stress, the ER stress/unfolded protein response, mitochondrial stress, or the DNA damage response, seem to also be involved in innate immunity, although the precise mechanisms by which they regulate the innate immune response are not yet defined. Of importance, these distinct constitutive cell-autonomous responses appear to be interconnected and can also be modulated by microbes and PRRs, which add further complexity to the interplay between innate immune signaling and cell-autonomous responses in the mediation of an efficient innate immune response.
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Affiliation(s)
- Julien Moretti
- Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - J Magarian Blander
- Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA; .,Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Graduate School of Biological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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56
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Grootjans J, Kaser A, Kaufman RJ, Blumberg RS. The unfolded protein response in immunity and inflammation. Nat Rev Immunol 2016; 16:469-84. [PMID: 27346803 DOI: 10.1038/nri.2016.62] [Citation(s) in RCA: 508] [Impact Index Per Article: 63.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The unfolded protein response (UPR) is a highly conserved pathway that allows the cell to manage endoplasmic reticulum (ER) stress that is imposed by the secretory demands associated with environmental forces. In this role, the UPR has increasingly been shown to have crucial functions in immunity and inflammation. In this Review, we discuss the importance of the UPR in the development, differentiation, function and survival of immune cells in meeting the needs of an immune response. In addition, we review current insights into how the UPR is involved in complex chronic inflammatory diseases and, through its role in immune regulation, antitumour responses.
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Affiliation(s)
- Joep Grootjans
- Division of Gastroenterology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, Massachusetts 02115, USA
| | - Arthur Kaser
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge CB2 0QQ, UK
| | - Randal J Kaufman
- Degenerative Diseases Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, USA
| | - Richard S Blumberg
- Division of Gastroenterology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, Massachusetts 02115, USA
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57
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Barel M, Harduin-Lepers A, Portier L, Slomianny MC, Charbit A. Host glycosylation pathways and the unfolded protein response contribute to the infection by Francisella. Cell Microbiol 2016; 18:1763-1781. [PMID: 27185209 DOI: 10.1111/cmi.12614] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 05/09/2016] [Accepted: 05/09/2016] [Indexed: 12/14/2022]
Abstract
Protein glycosylation processes play a crucial role in most physiological functions, including cell signalling, cellular differentiation and adhesion. We previously demonstrated that rapid deglycosylation of membrane proteins was specifically triggered after infection of human macrophages by the bacterial pathogen Francisella tularensis. Using a glycan processing gene microarray, we found here that Francisella infection modulated expression of numerous glycosidase and glycosyltransferase genes. Furthermore, analysis of cell extracts from infected macrophages by Lectin and Western blotting revealed an important increase of N- and O-protein glycosylation. We chose to focus in the present work on one of the O-glycosylated proteins identified by mass spectrometry, the multifunctional endoplasmic reticulum chaperone BiP (HSPA5/GRP78). We demonstrate that BiP expression is modulated upon Francisella infection and is required to support its intracellular multiplication. Moreover, we show that Francisella differentially modulates the BiP-dependent activation of three key proteins of the unfolded protein response (UPR), IRE1, PERK and ATF6. The effects exerted on human cells by Francisella may thus constitute a novel excample of UPR manipulation contributing to intracellular bacterial adaptation.
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Affiliation(s)
- Monique Barel
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Institut Necker Enfants-Malades INSERM, U1151, Team 11, Unité de Pathogénie des Infections Systémiques, Paris, France
| | - Anne Harduin-Lepers
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, FR 59000, Lille, France.,UGSF, Bat. C9, Université de Lille - Sciences et Technologies, 59655, Villeneuve d'Ascq, France
| | - Lucie Portier
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, FR 59000, Lille, France.,UGSF, Bat. C9, Université de Lille - Sciences et Technologies, 59655, Villeneuve d'Ascq, France
| | - Marie-Christine Slomianny
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, FR 59000, Lille, France.,UGSF, Bat. C9, Université de Lille - Sciences et Technologies, 59655, Villeneuve d'Ascq, France
| | - Alain Charbit
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Institut Necker Enfants-Malades INSERM, U1151, Team 11, Unité de Pathogénie des Infections Systémiques, Paris, France
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58
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Colaço HG, Moita LF. Initiation of innate immune responses by surveillance of homeostasis perturbations. FEBS J 2016; 283:2448-57. [PMID: 27037950 DOI: 10.1111/febs.13730] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 03/20/2016] [Accepted: 04/01/2016] [Indexed: 01/01/2023]
Abstract
Pathogen recognition, signaling transduction pathways, and effector mechanisms are necessary steps of innate immune responses that play key roles in the early phase of defense and in the stimulation of the later specific response of adaptive immunity. Here, we argue that in addition to the direct recognition of conserved common structural and functional molecular signatures of microorganisms using pattern recognition receptors, hosts can mount an immune response following the sensing of disruption in homeostasis as proximal reporters for infections. Surveillance of disruption of core cellular activities leading to defense responses is a flexible strategy that requires few additional components and that can effectively detect relevant threats. It is likely to be evolutionarily very conserved and ancient because it is operational in organisms that lack pattern recognition triggered immunity. A homeostasis disruption model of immune response initiation and modulation has broad implications for pathophysiology and treatment of disease and might constitute an often overlooked but central component of a comprehensive conceptual framework for innate immunity.
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Affiliation(s)
- Henrique G Colaço
- Innate Immunity and Inflammation Laboratory, Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Luis F Moita
- Innate Immunity and Inflammation Laboratory, Instituto Gulbenkian de Ciência, Oeiras, Portugal
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59
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Diverse roles of endoplasmic reticulum stress sensors in bacterial infection. Mol Cell Pediatr 2016; 3:9. [PMID: 26883353 PMCID: PMC4755955 DOI: 10.1186/s40348-016-0037-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 02/04/2016] [Indexed: 02/06/2023] Open
Abstract
Bacterial infection often leads to cellular damage, primarily marked by loss of cellular integrity and cell death. However, in recent years, it is being increasingly recognized that, in individual cells, there are graded responses collectively termed cell-autonomous defense mechanisms that induce cellular processes designed to limit cell damage, enable repair, and eliminate bacteria. Many of these responses are triggered not by detection of a particular bacterial effector or ligand but rather by their effects on key cellular processes and changes in homeostasis induced by microbial effectors when recognized. These in turn lead to a decrease in essential cellular functions such as protein translation or mitochondrial respiration and the induction of innate immune responses that may be specific to the cellular deficit induced. These processes are often associated with specific cell compartments, e.g., the endoplasmic reticulum (ER). Under non-infection conditions, these systems are generally involved in sensing cellular stress and in inducing and orchestrating the subsequent cellular response. Thus, perturbations of ER homeostasis result in accumulation of unfolded proteins which are detected by ER stress sensors in order to restore the normal condition. The ER is also important during bacterial infection, and bacterial effectors that activate the ER stress sensors have been discovered. Increasing evidence now indicate that bacteria have evolved strategies to differentially activate different arms of ER stress sensors resulting in specific host cell response. In this review, we will describe the mechanisms used by bacteria to activate the ER stress sensors and discuss their role during infection.
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60
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Dias-Teixeira KL, Calegari-Silva TC, dos Santos GRRM, Vitorino Dos Santos J, Lima C, Medina JM, Aktas BH, Lopes UG. The integrated endoplasmic reticulum stress response in Leishmania amazonensis macrophage infection: the role of X-box binding protein 1 transcription factor. FASEB J 2015; 30:1557-65. [PMID: 26678450 PMCID: PMC7163978 DOI: 10.1096/fj.15-281550] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 12/08/2015] [Indexed: 11/11/2022]
Abstract
Endoplasmic reticulum (ER) stress triggers the integrated ER-stress response (IERSR) that ensures cellular survival of ER stress and represents a primordial form of innate immunity. We investigated the role of IERSR duringLeishmania amazonensisinfection. Treatment of RAW 264.7 infected macrophages with the ER stress-inducing agent thapsigargin (TG; 1 μM) increasedL. amazonensisinfectivity in an IFN1-α receptor (IFNAR)-dependent manner. In Western blot assays, we showed thatL. amazonensisactivates the inositol-requiring enzyme (IRE1)/ X-box binding protein (XBP)-1-splicing arms of the IERSR in host cells. In chromatin immunoprecipitation (ChIP) assays, we showed an increased occupancy of enhancer and promoter sequences for theIfnbgene by XBP1 in infected RAW 264.7 cells. Knocking down XBP1 expression by transducing RAW 264.7 cells with the short hairpin XBP1 lentiviral vector significantly reduced the parasite proliferation associated with impaired translocation of phosphorylated IFN regulatory transcription factor (IRF)-3 to the nucleus and a decrease in IFN1-β expression. Knocking down XBP1 expression also increased NO concentration, as determined by Griess reaction and reduced the expression of antioxidant genes, such as heme oxygenase (HO)-1, that protect parasites from oxidative stress. We conclude thatL. amazonensisactivation of XBP1 plays a critical role in infection by protecting the parasites from oxidative stress and increasing IFN1-β expression.-Dias-Teixeira, K. L., Calegari-Silva, T. C., Dos Santos, G. R. R. M., Vitorino dos Santos, J., Lima, C., Medina, J. M., Aktas, B. H., Lopes, U. G. The integrated endoplasmic reticulum stress response inLeishmania amazonensismacrophage infection: the role of X-box binding protein 1 transcription factor.
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Affiliation(s)
- Karina Luiza Dias-Teixeira
- *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Teresa Cristina Calegari-Silva
- *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Guilherme R R M dos Santos
- *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - José Vitorino Dos Santos
- *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Carolina Lima
- *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Jorge Mansur Medina
- *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Bertal Huseyin Aktas
- *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Ulisses G Lopes
- *Laboratório de Parasitologia Molecular, Instituto de Biofísica Carlos Chagas Filho, and Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; and Hematology Laboratory for Translation, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
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61
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Inhibition of host cell translation elongation by Legionella pneumophila blocks the host cell unfolded protein response. Proc Natl Acad Sci U S A 2015; 112:E6790-7. [PMID: 26598709 DOI: 10.1073/pnas.1508716112] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Cells of the innate immune system recognize bacterial pathogens by detecting common microbial patterns as well as pathogen-specific activities. One system that responds to these stimuli is the IRE1 branch of the unfolded protein response (UPR), a sensor of endoplasmic reticulum (ER) stress. Activation of IRE1, in the context of Toll-like receptor (TLR) signaling, induces strong proinflammatory cytokine induction. We show here that Legionella pneumophila, an intravacuolar pathogen that replicates in an ER-associated compartment, blocks activation of the IRE1 pathway despite presenting pathogen products that stimulate this response. L. pneumophila TLR ligands induced the splicing of mRNA encoding XBP1s, the main target of IRE1 activity. L. pneumophila was able to inhibit both chemical and bacterial induction of XBP1 splicing via bacterial translocated proteins that interfere with host protein translation. A strain lacking five translocated translation elongation inhibitors was unable to block XBP1 splicing, but this could be rescued by expression of a single such inhibitor, consistent with limitation of the response by translation elongation inhibitors. Chemical inhibition of translation elongation blocked pattern recognition receptor-mediated XBP1 splicing, mimicking the effects of the bacterial translation inhibitors. In contrast, host cell-promoted inhibition of translation initiation in response to the pathogen was ineffective in blocking XBP1 splicing, demonstrating the need for the elongation inhibitors for protection from the UPR. The inhibition of host translation elongation may be a common strategy used by pathogens to limit the innate immune response by interfering with signaling via the UPR.
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62
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Barnett TC, Cole JN, Rivera-Hernandez T, Henningham A, Paton JC, Nizet V, Walker MJ. Streptococcal toxins: role in pathogenesis and disease. Cell Microbiol 2015; 17:1721-41. [PMID: 26433203 DOI: 10.1111/cmi.12531] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/13/2015] [Accepted: 09/02/2015] [Indexed: 12/15/2022]
Abstract
Group A Streptococcus (Streptococcus pyogenes), group B Streptococcus (Streptococcus agalactiae) and Streptococcus pneumoniae (pneumococcus) are host-adapted bacterial pathogens among the leading infectious causes of human morbidity and mortality. These microbes and related members of the genus Streptococcus produce an array of toxins that act against human cells or tissues, resulting in impaired immune responses and subversion of host physiological processes to benefit the invading microorganism. This toxin repertoire includes haemolysins, proteases, superantigens and other agents that ultimately enhance colonization and survival within the host and promote dissemination of the pathogen.
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Affiliation(s)
- Timothy C Barnett
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Jason N Cole
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia.,Department of Pediatrics and Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, USA
| | - Tania Rivera-Hernandez
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Anna Henningham
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia.,Department of Pediatrics and Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, USA
| | - James C Paton
- Research Centre for Infectious Diseases, Department of Molecular and Cellular Biology, School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Victor Nizet
- Department of Pediatrics and Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California, USA
| | - Mark J Walker
- Australian Infectious Diseases Research Centre and School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Queensland, Australia
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63
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Hashino M, Tachibana M, Nishida T, Hara H, Tsuchiya K, Mitsuyama M, Watanabe K, Shimizu T, Watarai M. Inactivation of the MAPK signaling pathway by Listeria monocytogenes infection promotes trophoblast giant cell death. Front Microbiol 2015; 6:1145. [PMID: 26528279 PMCID: PMC4607873 DOI: 10.3389/fmicb.2015.01145] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 10/05/2015] [Indexed: 12/21/2022] Open
Abstract
Listeria monocytogenes has a well-characterized ability to cross the placental barrier, resulting in spontaneous abortion and fetal infections. However, the mechanisms resulting in infection-associated abortion are not fully understood. In this study, we demonstrate that the dephosphorylation of MAPK family proteins caused by L. monocytogenes infection of trophoblast giant (TG) cells, which are placental immune cells, contributes to infectious abortion. Dephosphorylation of c-Jun, p38, and ERK1/2 was observed in infected TG cells, causing the downregulation of cytoprotective heme oxygenase (HO)-1. Blocking the dephosphorylation of proteins, including MAPK family proteins, inhibited the decrease in HO-1 expression. Treatment with MAPK inhibitors inhibited bacterial internalization into TG cells. Moreover, Toll-like receptor 2 involved in the expression of MAPK family proteins. Infection with a listeriolysin O-deleted mutant impaired dephosphorylation of MAPK family proteins in TG cells and did not induce infectious abortion in a mouse model. These results suggest that inactivation of the MAPK pathway by L. monocytogenes induces TG cell death and causes infectious abortion.
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Affiliation(s)
- Masanori Hashino
- The United Graduate School of Veterinary Science, Yamaguchi University, Yoshida Campus Yamaguchi, Japan
| | - Masato Tachibana
- The United Graduate School of Veterinary Science, Yamaguchi University, Yoshida Campus Yamaguchi, Japan ; Division of Biomedical Food Research, National Institute of Health Sciences Tokyo, Japan
| | - Takashi Nishida
- The United Graduate School of Veterinary Science, Yamaguchi University, Yoshida Campus Yamaguchi, Japan
| | - Hideki Hara
- Department of Microbiology, Graduate School of Medicine, Kyoto University Kyoto, Japan ; Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School Ann Arbor, MI, USA
| | - Kohsuke Tsuchiya
- Department of Microbiology, Graduate School of Medicine, Kyoto University Kyoto, Japan ; Division of Immunology and Molecular Biology, Cancer Research Institute, Kanazawa University Kanazawa, Japan
| | - Masao Mitsuyama
- Department of Microbiology, Graduate School of Medicine, Kyoto University Kyoto, Japan ; Graduate School of Advanced Integrated Studies in Human Survivability, Kyoto University Kyoto, Japan
| | - Kenta Watanabe
- The United Graduate School of Veterinary Science, Yamaguchi University, Yoshida Campus Yamaguchi, Japan ; Laboratory of Veterinary Public Health, Joint Faculty of Veterinary Medicine, Yamaguchi University at Yamaguchi Yamaguchi, Japan
| | - Takashi Shimizu
- The United Graduate School of Veterinary Science, Yamaguchi University, Yoshida Campus Yamaguchi, Japan ; Laboratory of Veterinary Public Health, Joint Faculty of Veterinary Medicine, Yamaguchi University at Yamaguchi Yamaguchi, Japan
| | - Masahisa Watarai
- The United Graduate School of Veterinary Science, Yamaguchi University, Yoshida Campus Yamaguchi, Japan ; Laboratory of Veterinary Public Health, Joint Faculty of Veterinary Medicine, Yamaguchi University at Yamaguchi Yamaguchi, Japan
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64
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Bronner DN, Abuaita BH, Chen X, Fitzgerald KA, Nuñez G, He Y, Yin XM, O'Riordan MXD. Endoplasmic Reticulum Stress Activates the Inflammasome via NLRP3- and Caspase-2-Driven Mitochondrial Damage. Immunity 2015; 43:451-62. [PMID: 26341399 DOI: 10.1016/j.immuni.2015.08.008] [Citation(s) in RCA: 305] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 06/01/2015] [Accepted: 07/28/2015] [Indexed: 01/01/2023]
Abstract
Endoplasmic reticulum (ER) stress is observed in many human diseases, often associated with inflammation. ER stress can trigger inflammation through nucleotide-binding domain and leucine-rich repeat containing (NLRP3) inflammasome, which might stimulate inflammasome formation by association with damaged mitochondria. How ER stress triggers mitochondrial dysfunction and inflammasome activation is ill defined. Here we have used an infection model to show that the IRE1α ER stress sensor regulates regulated mitochondrial dysfunction through an NLRP3-mediated feed-forward loop, independently of ASC. IRE1α activation increased mitochondrial reactive oxygen species, promoting NLRP3 association with mitochondria. NLRP3 was required for ER stress-induced cleavage of caspase-2 and the pro-apoptotic factor, Bid, leading to subsequent release of mitochondrial contents. Caspase-2 and Bid were necessary for activation of the canonical inflammasome by infection-associated or general ER stress. These data identify an NLRP3-caspase-2-dependent mechanism that relays ER stress to the mitochondria to promote inflammation, integrating cellular stress and innate immunity.
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Affiliation(s)
- Denise N Bronner
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Basel H Abuaita
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Xiaoyun Chen
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Katherine A Fitzgerald
- Division of Infectious Diseases and Immunology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Gabriel Nuñez
- Department of Pathology, University of Michigan Medical School, Ann Arbor, MI 48109, USA; Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Yongqun He
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109, USA; Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI 48109 USA; Unit for Laboratory Animal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109 USA
| | - Xiao-Ming Yin
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Mary X D O'Riordan
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109, USA; Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI 48109 USA.
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65
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Treacy-Abarca S, Mukherjee S. Legionella suppresses the host unfolded protein response via multiple mechanisms. Nat Commun 2015. [PMID: 26219498 PMCID: PMC4519984 DOI: 10.1038/ncomms8887] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The intracellular pathogen, Legionella pneumophila, secretes ∼300 effector proteins to modulate the host environment. Given the intimate interaction between L. pneumophila and the endoplasmic reticulum, we investigated the role of the host unfolded protein response (UPR) during L. pneumophila infection. Interestingly, we show that the host identifies L. pneumophila infection as a form of endoplasmic reticulum stress and the sensor pATF6 is processed to generate pATF6(N), a transcriptional activator of downstream UPR genes. However, L. pneumophila is able to suppress the UPR and block the translation of prototypical UPR genes, BiP and CHOP. Furthermore, biochemical studies reveal that L. pneumophila uses two effectors (Lgt1 and Lgt2) to inhibit the splicing of XBP1u mRNA to spliced XBP1 (XBP1s), an UPR response regulator. Thus, we demonstrate that L. pneumophila is able to inhibit the UPR by multiple mechanisms including blocking XBP1u splicing and causing translational repression. This observation highlights the utility of L. pneumophila as a powerful tool for studying a critical protein homeostasis regulator. The bacterium Legionella pneumophila, a causative agent of severe pneumonia, replicates inside an endoplasmic reticulum-like organelle in the host cells. Here, Treacy-Abarca and Mukherjee show that the pathogen dampens the host's unfolded protein response (UPR) pathway by multiple mechanisms.
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Affiliation(s)
- Sean Treacy-Abarca
- 1] Department of Microbiology and Immunology, University of California, San Francisco, 513 Parnassus Avenue, San Francisco, California 94143-0552, USA [2] Department of Microbiology and Immunology, George Williams Hooper Foundation, 513 Parnassus Avenue, Box 0552, Rm HSW 1522, San Francisco, California 94143-0552, USA
| | - Shaeri Mukherjee
- 1] Department of Microbiology and Immunology, University of California, San Francisco, 513 Parnassus Avenue, San Francisco, California 94143-0552, USA [2] Department of Microbiology and Immunology, George Williams Hooper Foundation, 513 Parnassus Avenue, Box 0552, Rm HSW 1522, San Francisco, California 94143-0552, USA
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66
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Bacterial Internalization, Localization, and Effectors Shape the Epithelial Immune Response during Shigella flexneri Infection. Infect Immun 2015; 83:3624-37. [PMID: 26123804 DOI: 10.1128/iai.00574-15] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 06/26/2015] [Indexed: 01/28/2023] Open
Abstract
Intracellular pathogens are differentially sensed by the compartmentalized host immune system. Nevertheless, gene expression studies of infected cells commonly average the immune responses, neglecting the precise pathogen localization. To overcome this limitation, we dissected the transcriptional immune response to Shigella flexneri across different infection stages in bulk and single cells. This identified six distinct transcriptional profiles characterizing the dynamic, multilayered host response in both bystander and infected cells. These profiles were regulated by external and internal danger signals, as well as whether bacteria were membrane bound or cytosolic. We found that bacterial internalization triggers a complex, effector-independent response in bystander cells, possibly to compensate for the undermined host gene expression in infected cells caused by bacterial effectors, particularly OspF. Single-cell analysis revealed an important bacterial strategy to subvert host responses in infected cells, demonstrating that OspF disrupts concomitant gene expression of proinflammatory, apoptosis, and stress pathways within cells. This study points to novel mechanisms through which bacterial internalization, localization, and injected effectors orchestrate immune response transcriptional signatures.
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67
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Inácio P, Zuzarte-Luís V, Ruivo MTG, Falkard B, Nagaraj N, Rooijers K, Mann M, Mair G, Fidock DA, Mota MM. Parasite-induced ER stress response in hepatocytes facilitates Plasmodium liver stage infection. EMBO Rep 2015; 16:955-64. [PMID: 26113366 DOI: 10.15252/embr.201439979] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 06/02/2015] [Indexed: 12/15/2022] Open
Abstract
Upon infection of a mammalian host, Plasmodium parasites first replicate inside hepatocytes, generating thousands of new parasites. Although Plasmodium intra-hepatic development represents a substantial metabolic challenge to the host hepatocyte, how infected cells respond to and integrate this stress remains poorly understood. Here, we present proteomic and transcriptomic analyses, revealing that the endoplasmic reticulum (ER)-resident unfolded protein response (UPR) is activated in host hepatocytes upon Plasmodium berghei infection. The expression of XBP1s--the active form of the UPR mediator XBP1--and the liver-specific UPR mediator CREBH is induced by P. berghei infection in vivo. Furthermore, this UPR induction increases parasite liver burden. Altogether, our data suggest that ER stress is a central feature of P. berghei intra-hepatic development, contributing to the success of infection.
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Affiliation(s)
- Patricia Inácio
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Vanessa Zuzarte-Luís
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Margarida T G Ruivo
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Brie Falkard
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, USA
| | - Nagarjuna Nagaraj
- Department of Proteomics and Signal Transduction, Max Planck Institute for Biochemistry, Martinsried, Germany
| | - Koos Rooijers
- Division of Gene Regulation, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Matthias Mann
- Department of Proteomics and Signal Transduction, Max Planck Institute for Biochemistry, Martinsried, Germany
| | - Gunnar Mair
- Department of Parasitology, University of Heidelberg, Heidelberg, Germany
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, USA Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, NY, USA
| | - Maria M Mota
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
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Cajnko MM, Marušić M, Kisovec M, Rojko N, Benčina M, Caserman S, Anderluh G. Listeriolysin O Affects the Permeability of Caco-2 Monolayer in a Pore-Dependent and Ca2+-Independent Manner. PLoS One 2015; 10:e0130471. [PMID: 26087154 PMCID: PMC4472510 DOI: 10.1371/journal.pone.0130471] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Accepted: 05/20/2015] [Indexed: 12/20/2022] Open
Abstract
Listeria monocytogenes is a food and soil-borne pathogen that secretes a pore-forming toxin listeriolysin O (LLO) as its major virulence factor. We tested the effects of LLO on an intestinal epithelial cell line Caco-2 and compared them to an unrelated pore-forming toxin equinatoxin II (EqtII). Results showed that apical application of both toxins causes a significant drop in transepithelial electrical resistance (TEER), with higher LLO concentrations or prolonged exposure time needed to achieve the same magnitude of response than with EqtII. The drop in TEER was due to pore formation and coincided with rearrangement of claudin-1 within tight junctions and associated actin cytoskeleton; however, no significant increase in permeability to fluorescein or 3 kDa FITC-dextran was observed. Influx of calcium after pore formation affected the magnitude of the drop in TEER. Both toxins exhibit similar effects on epithelium morphology and physiology. Importantly, LLO action upon the membrane is much slower and results in compromised epithelium on a longer time scale at lower concentrations than EqtII. This could favor listerial invasion in hosts resistant to E-cadherin related infection.
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Affiliation(s)
- Miša Mojca Cajnko
- Laboratory for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Maja Marušić
- Laboratory for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Matic Kisovec
- Laboratory for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Nejc Rojko
- Laboratory for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Mojca Benčina
- Laboratory for Biotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Simon Caserman
- Laboratory for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Gregor Anderluh
- Laboratory for Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000, Ljubljana, Slovenia
- * E-mail:
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69
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Organelle targeting during bacterial infection: insights from Listeria. Trends Cell Biol 2015; 25:330-8. [DOI: 10.1016/j.tcb.2015.01.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 01/13/2015] [Accepted: 01/15/2015] [Indexed: 10/24/2022]
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70
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Sousa S, Mesquita FS, Cabanes D. Old war, new battle, new fighters! J Infect Dis 2015; 211:1361-3. [PMID: 25231016 DOI: 10.1093/infdis/jiu521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 09/11/2014] [Indexed: 11/13/2022] Open
Affiliation(s)
- Sandra Sousa
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
| | | | - Didier Cabanes
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
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71
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Pillich H, Chakraborty T, Mraheil MA. Cell-autonomous responses in Listeria monocytogenes infection. Future Microbiol 2015; 10:583-97. [DOI: 10.2217/fmb.15.4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
ABSTRACT Listeria monocytogenes is a facultative intracellular bacterium causing listeriosis, a food-borne infection with a high mortality rate. The mechanisms and the role of cells and tissular components in generating protective adaptive immune responses are well studied, and cell biological studies provide a detailed understanding of the processes targeted by the bacterial products. Much less is known of the cellular responses activated to limit infection in individual cells when confronted with stress or infection. Eukaryotic cellular responses depend on multitiered homeostatic systems that ensure maintenance of proteostatis, organellar integrity, function and turnover, and overall cellular viability (‘the cell-autonomous response’). Here, we review the cell-autonomous responses induced during extracellular and intracellular L. monocytogenes growth and discuss their contribution to limiting infection.
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Affiliation(s)
- Helena Pillich
- Institute of Medical Microbiology, German Center for Infection Giessen-Marburg-Langen Site, Justus Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany
| | - Trinad Chakraborty
- Institute of Medical Microbiology, German Center for Infection Giessen-Marburg-Langen Site, Justus Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany
| | - Mobarak Abu Mraheil
- Institute of Medical Microbiology, German Center for Infection Giessen-Marburg-Langen Site, Justus Liebig University Giessen, Schubertstrasse 81, 35392 Giessen, Germany
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72
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Biological effects of listeriolysin O: implications for vaccination. BIOMED RESEARCH INTERNATIONAL 2015; 2015:360741. [PMID: 25874208 PMCID: PMC4385656 DOI: 10.1155/2015/360741] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/25/2014] [Revised: 02/13/2015] [Accepted: 02/14/2015] [Indexed: 12/13/2022]
Abstract
Listeriolysin O (LLO) is a thiol-activated cholesterol-dependent pore-forming toxin and the major virulence factor of Listeria monocytogenes (LM). Extensive research in recent years has revealed that LLO exerts a wide array of biological activities, during the infection by LM or by itself as recombinant antigen. The spectrum of biological activities induced by LLO includes cytotoxicity, apoptosis induction, endoplasmic reticulum stress response, modulation of gene expression, intracellular calcium oscillations, and proinflammatory activity. In addition, LLO is a highly immunogenic toxin and the major target for innate and adaptive immune responses in different animal models and humans. Recently, the crystal structure of LLO has been published in detail. Here, we review the structure-function relationship for this fascinating microbial molecule, highlighting the potential uses of LLO in the fields of biomedicine and biotechnology, particularly in vaccination.
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73
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Shima K, Klinger M, Schütze S, Kaufhold I, Solbach W, Reiling N, Rupp J. The role of endoplasmic reticulum-related BiP/GRP78 in interferon gamma-induced persistent Chlamydia pneumoniae infection. Cell Microbiol 2015; 17:923-34. [PMID: 25588955 DOI: 10.1111/cmi.12416] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 12/12/2014] [Accepted: 01/01/2015] [Indexed: 12/26/2022]
Abstract
Direct interaction of Chlamydiae with the endoplasmic reticulum (ER) is essential in intracellular productive infection. However, little is known about the interplay between Chlamydiae and the ER under cellular stress conditions that are observed in interferon gamma (IFN-γ) induced chlamydial persistent infection. ER stress responses are centrally regulated by the unfolded protein response (UPR) under the control of the ER chaperone BiP/GRP78 to maintain cellular homeostasis. In this study, we could show that the ER directly contacted with productive and IFN-γ-induced persistent inclusions of Chlamydia pneumoniae (Cpn). BiP/GRP78 induction was observed in the early phase but not in the late phase of IFN-γ-induced persistent infection. Enhanced BiP/GRP78 expression in the early phase of IFN-γ-induced persistent Cpn infection was accompanied by phosphorylation of the eukaryotic initiation factor-2α (eIF2α) and down-regulation of the vesicle-associated membrane protein-associated protein B. Loss of BiP/GRP78 function resulted in enhanced phosphorylation of eIF2α and increased host cell apoptosis. In contrast, enhanced BiP/GRP78 expression in IFN-γ-induced persistent Cpn infection attenuated phosphorylation of eIF2α upon an exogenous ER stress inducer. In conclusion, ER-related BiP/GRP78 plays a key role to restore cells from stress conditions that are observed in the early phase of IFN-γ-induced persistent infection.
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Affiliation(s)
- Kensuke Shima
- Department of Molecular and Clinical Infectious Diseases, University of Lübeck, Ratzeburger Allee 160, Lübeck, 23538, Germany
| | | | - Stefan Schütze
- Institute of Immunology, University of Kiel, Kiel, Germany
| | - Inga Kaufhold
- Department of Molecular and Clinical Infectious Diseases, University of Lübeck, Ratzeburger Allee 160, Lübeck, 23538, Germany
| | - Werner Solbach
- Institute of Medical Microbiology and Hygiene, University of Lübeck, Lübeck, Germany
| | - Norbert Reiling
- Division of Microbial Interface Biology, Research Center Borstel, Leibniz Center for Medicine and Biosciences, Borstel, Germany
| | - Jan Rupp
- Department of Molecular and Clinical Infectious Diseases, University of Lübeck, Ratzeburger Allee 160, Lübeck, 23538, Germany
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Argüello RJ, Rodriguez Rodrigues C, Gatti E, Pierre P. Protein synthesis regulation, a pillar of strength for innate immunity? Curr Opin Immunol 2014; 32:28-35. [PMID: 25553394 DOI: 10.1016/j.coi.2014.12.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 12/04/2014] [Accepted: 12/10/2014] [Indexed: 12/31/2022]
Abstract
Recognition of pathogen derived molecules by Pattern Recognition Receptors (PRR) induces the production of cytokines (i.e. type I interferons) that stimulate the surrounding cells to transcribe and translate hundreds of genes, in order to prevent further infection and organize the immune response. Here, we report on the rising matter that metabolism sensing and gene expression control at the level of mRNA translation, allow swift responses that mobilize host defenses and coordinate innate responses to infection.
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Affiliation(s)
- Rafael J Argüello
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France
| | - Christian Rodriguez Rodrigues
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France
| | - Evelina Gatti
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Philippe Pierre
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
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Emerging functions of the unfolded protein response in immunity. Nat Immunol 2014; 15:910-9. [PMID: 25232821 DOI: 10.1038/ni.2991] [Citation(s) in RCA: 170] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 08/18/2014] [Indexed: 12/14/2022]
Abstract
The unfolded protein response (UPR) has traditionally been viewed as an adaptive response triggered by the accumulation of unfolded proteins in the endoplasmic reticulum (ER) and aimed at restoring ER function. The UPR can also be an anticipatory response that is activated well before the disruption of protein homeostasis. UPR signaling intersects at many levels with the innate and adaptive immune responses. In some types of cells of the immune system, such as dendritic cells (DCs) and B cells, particular sensors that detect the UPR seem to be constitutively active in the absence of induction of the traditional UPR gene program and are necessary for antigen presentation and immunoglobulin synthesis. The UPR also influences signaling via Toll-like receptors (TLRs) and activation of the transcription factor NF-κB, and some pathogens subvert the UPR. This Review summarizes these emerging noncanonical functions of the UPR in immunity.
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76
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Bacteria, the endoplasmic reticulum and the unfolded protein response: friends or foes? Nat Rev Microbiol 2014; 13:71-82. [PMID: 25534809 DOI: 10.1038/nrmicro3393] [Citation(s) in RCA: 154] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The unfolded protein response (UPR) is a cytoprotective response that is aimed at restoring cellular homeostasis following physiological stress exerted on the endoplasmic reticulum (ER), which also invokes innate immune signalling in response to invading microorganisms. Although it has been known for some time that the UPR is modulated by various viruses, recent evidence indicates that it also has multiple roles during bacterial infections. In this Review, we describe how bacteria interact with the ER, including how bacteria induce the UPR, how subversion of the UPR promotes bacterial proliferation and how the UPR contributes to innate immune responses against invading bacteria.
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Loose M, Hudel M, Zimmer KP, Garcia E, Hammerschmidt S, Lucas R, Chakraborty T, Pillich H. Pneumococcal hydrogen peroxide-induced stress signaling regulates inflammatory genes. J Infect Dis 2014; 211:306-16. [PMID: 25183769 DOI: 10.1093/infdis/jiu428] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Microbial infections can induce aberrant responses in cellular stress pathways, leading to translational attenuation, metabolic restriction, and activation of oxidative stress, with detrimental effects on cell survival. Here we show that infection of human airway epithelial cells with Streptococcus pneumoniae leads to induction of endoplasmic reticulum (ER) and oxidative stress, activation of mitogen-associated protein kinase (MAPK) signaling pathways, and regulation of their respective target genes. We identify pneumococcal H2O2 as the causative agent for these responses, as both catalase-treated and pyruvate oxidase-deficient bacteria lacked these activities. Pneumococcal H2O2 induced nuclear NF-κB translocation and transcription of proinflammatory cytokines. Inhibition of translational arrest and ER stress by salubrinal or of MAPK signaling pathways attenuate cytokine transcription. These results provide strong evidence for the notion that inhibition of translation is an important host pathway in monitoring harmful pathogen-associated activities, thereby enabling differentiation between pathogenic and nonpathogenic bacteria.
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Affiliation(s)
- Maria Loose
- Institute for Medical Microbiology, German Center for Infection Giessen-Marburg-Langen Site
| | - Martina Hudel
- Institute for Medical Microbiology, German Center for Infection Giessen-Marburg-Langen Site
| | | | - Ernesto Garcia
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, and Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, Madrid, Spain
| | - Sven Hammerschmidt
- Department Genetics of Microorganisms, Interfaculty Institute for Genetics and Functional Genomics, Ernst Moritz Arndt University of Greifswald, Germany
| | - Rudolf Lucas
- Vascular Biology Center, Department of Pharmacology and Toxicology, Georgia Health Sciences University, Augusta
| | - Trinad Chakraborty
- Institute for Medical Microbiology, German Center for Infection Giessen-Marburg-Langen Site
| | - Helena Pillich
- Institute for Medical Microbiology, German Center for Infection Giessen-Marburg-Langen Site
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78
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Häcker G. ER-stress and apoptosis: molecular mechanisms and potential relevance in infection. Microbes Infect 2014; 16:805-10. [PMID: 25172397 DOI: 10.1016/j.micinf.2014.08.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 08/18/2014] [Accepted: 08/19/2014] [Indexed: 02/07/2023]
Abstract
During ER-stress, one of the responses a cell can choose is apoptosis. Apoptosis generally is a cell's preferred response when other control mechanisms are overwhelmed. We now have a reasonably clear molecular picture what is happening once the apoptotic apparatus has been started. Unclear however are the majority of the upstream pathways that connect other signalling to apoptosis. During ER-stress, confirmed apoptosis-regulating targets are pro- and anti-apoptotic proteins of the Bcl-2-family, whose concerted action induces apoptosis. I will here discuss how mitochondrial apoptosis is triggered, how this is linked to the ER-stress response and in what way this may be relevant during microbial infections.
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Affiliation(s)
- Georg Häcker
- Institute for Medical Microbiology and Hygiene, University Medical Centre Freiburg, Hermann Herder-Str. 11, D-79104 Freiburg, Germany.
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79
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Cabrita P, Trigo MJ, Ferreira RB, Brito L. Is the exoproteome important for bacterial pathogenesis? Lessons learned from interstrain exoprotein diversity in Listeria monocytogenes grown at different temperatures. OMICS-A JOURNAL OF INTEGRATIVE BIOLOGY 2014; 18:553-69. [PMID: 25127015 DOI: 10.1089/omi.2013.0151] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Bacterial exoproteomes vary in composition and quantity among species and within each species, depending on the environmental conditions to which the cells are exposed. This article critically reviews the literature available on exoproteins synthesized by the foodborne pathogenic bacterium Listeria monocytogenes grown at different temperatures. The main challenges posed for exoproteome analyses and the strategies that are being used to overcome these constraints are discussed. Over thirty exoproteins from L. monocytogenes are considered, and the multifunctionality of some of them is discussed. Thus, at the host temperature of 37°C, good examples are provided by Lmo0443, a potential marker for low virulence, and by the virulence factors internalin C (InlC) and listeriolysin O (LLO). Based on the reported LLO-induced mucin exocytosis, a model is proposed for the involvement of extracellular LLO in optimizing the conditions for InlC intervention in the invasion of intestinal epithelial cells. At lower growth temperatures, exoproteins such as flagellin (FlaA) and oligopeptide permease (OppA) may explain the persistence of particular strains in the food industry environment, eventually allowing the development of new tools to eradicate L. monocytogenes, a major concern for public health.
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Affiliation(s)
- Paula Cabrita
- 1 CBAA/DRAT-Departamento dos Recursos Naturais, Ambiente e Território, Instituto Superior de Agronomia, University of Lisbon , Lisbon, Portugal
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80
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Baruch M, Hertzog BB, Ravins M, Anand A, Cheng CY, Biswas D, Tirosh B, Hanski E. Induction of endoplasmic reticulum stress and unfolded protein response constitutes a pathogenic strategy of group A streptococcus. Front Cell Infect Microbiol 2014; 4:105. [PMID: 25136516 PMCID: PMC4120759 DOI: 10.3389/fcimb.2014.00105] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 07/14/2014] [Indexed: 11/30/2022] Open
Abstract
The connection between bacterial pathogens and unfolded protein response (UPR) is poorly explored. In this review we highlight the evidence showing that group A streptococcus (GAS) induces endoplasmic reticulum (ER) stress and UPR through which it captures the amino acid asparagine (ASN) from the host. GAS acts extracellularly and during adherence to host cells it delivers the hemolysin toxins; streptolysin O (SLO) and streptolysin S (SLS). By poorly understood pathways, these toxins trigger UPR leading to the induction of the transcriptional regulator ATF4 and consequently to the upregulation of asparagine synthetase (ASNS) transcription leading to production and release of ASN. GAS senses ASN and alters gene expression profile accordingly, and increases the rate of multiplication. We suggest that induction of UPR by GAS and by other bacterial pathogens represent means through which bacterial pathogens gain nutrients from the host, obviating the need to become internalized or inflict irreversible cell damage.
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Affiliation(s)
- Moshe Baruch
- Department of Microbiology and Molecular Genetics, Faculty of Medicine, The Hebrew University of Jerusalem (HUJI) Jerusalem, Israel
| | - Baruch B Hertzog
- Department of Microbiology and Molecular Genetics, Faculty of Medicine, The Hebrew University of Jerusalem (HUJI) Jerusalem, Israel
| | - Miriam Ravins
- Department of Microbiology and Molecular Genetics, Faculty of Medicine, The Hebrew University of Jerusalem (HUJI) Jerusalem, Israel
| | - Aparna Anand
- Department of Microbiology and Molecular Genetics, Faculty of Medicine, The Hebrew University of Jerusalem (HUJI) Jerusalem, Israel
| | - Catherine Youting Cheng
- Department of Microbiology, Center for Research Excellence and Technological Enterprise (CREATE), National University of Singapore (NUS) and NUS-HUJI Singapore
| | - Debabrata Biswas
- Department of Microbiology and Molecular Genetics, Faculty of Medicine, The Hebrew University of Jerusalem (HUJI) Jerusalem, Israel ; Department of Microbiology, Center for Research Excellence and Technological Enterprise (CREATE), National University of Singapore (NUS) and NUS-HUJI Singapore
| | - Boaz Tirosh
- The School of Pharmacy, Institute for Drug Research, The Hebrew University of Jerusalem Jerusalem, Israel
| | - Emanuel Hanski
- Department of Microbiology and Molecular Genetics, Faculty of Medicine, The Hebrew University of Jerusalem (HUJI) Jerusalem, Israel ; Department of Microbiology, Center for Research Excellence and Technological Enterprise (CREATE), National University of Singapore (NUS) and NUS-HUJI Singapore
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81
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Banerjee C, Singh A, Das TK, Raman R, Shrivastava A, Mazumder S. Ameliorating ER-stress attenuates Aeromonas hydrophila-induced mitochondrial dysfunctioning and caspase mediated HKM apoptosis in Clarias batrachus. Sci Rep 2014; 4:5820. [PMID: 25059203 PMCID: PMC5376045 DOI: 10.1038/srep05820] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 06/16/2014] [Indexed: 02/07/2023] Open
Abstract
Endoplasmic reticulum (ER)-stress and unfolding protein response (UPR) has not been implied in Aeromonas hydrophila-pathogenicity. We report increased expression of the ER-stress markers: CHOP, BiP and phospho-eIF2α in A. hydrophila-infected headkidney macrophages (HKM) in Clarias batrachus. Pre-treatment with ER-stress inhibitor, 4-PBA alleviated ER-stress and HKM apoptosis suggesting ER-UPR critical for the process. The ER-Ca(2+) released via inositol-triphosphate and ryanodine receptors induced calpain-2 mediated superoxide ion generation and consequent NF-κB activation. Inhibiting NF-κB activation attenuated NO production suggesting the pro-apoptotic role of NF-κB on HKM pathology. Calpain-2 activated caspase-12 to intensify the apoptotic cascade through mitochondrial-membrane potential (ψm) dissipation and caspase-9 activation. Altered mitochondrial ultra-structure consequent to ER-Ca(2+) uptake via uniporters reduced ψm and released cytochrome C. Nitric oxide induced the cGMP/PKG-dependent activation of caspase-8 and truncated-Bid formation. Both the caspases converge onto caspase-3 to execute HKM apoptosis. These findings offer a possible molecular explanation for A. hydrophila pathogenicity.
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Affiliation(s)
- Chaitali Banerjee
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi 110 007, India
| | - Ambika Singh
- Gut Biology Laboratory, Department of Zoology, University of Delhi, Delhi 110 007, India
| | - Taposh Kumar Das
- Department of Anatomy, All India Institute of Medical Sciences, Delhi 110 029, India
| | - Rajagopal Raman
- Gut Biology Laboratory, Department of Zoology, University of Delhi, Delhi 110 007, India
| | - Anju Shrivastava
- Cell Signalling and Molecular Immunology Laboratory, Department of Zoology, University of Delhi, Delhi 110 007, India
| | - Shibnath Mazumder
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi 110 007, India
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Mehlitz A, Karunakaran K, Herweg JA, Krohne G, van de Linde S, Rieck E, Sauer M, Rudel T. The chlamydial organism Simkania negevensis forms ER vacuole contact sites and inhibits ER-stress. Cell Microbiol 2014; 16:1224-43. [PMID: 24528559 DOI: 10.1111/cmi.12278] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 01/28/2014] [Accepted: 02/05/2014] [Indexed: 01/01/2023]
Abstract
Most intracellular bacterial pathogens reside within membrane-surrounded host-derived vacuoles. Few of these bacteria exploit membranes from the host's endoplasmic reticulum (ER) to form a replicative vacuole. Here, we describe the formation of ER-vacuole contact sites as part of the replicative niche of the chlamydial organism Simkania negevensis. Formation of ER-vacuole contact sites is evolutionary conserved in the distantly related protozoan host Acanthamoeba castellanii. Simkania growth is accompanied by mitochondria associating with the Simkania-containing vacuole (SCV). Super-resolution microscopy as well as 3D reconstruction from electron micrographs of serial ultra-thin sections revealed a single vacuolar system forming extensive ER-SCV contact sites on the Simkania vacuolar surface. Simkania infection induced an ER-stress response, which was later downregulated. Induction of ER-stress with Thapsigargin or Tunicamycin was strongly inhibited in cells infected with Simkania. Inhibition of ER-stress was required for inclusion formation and efficient growth, demonstrating a role of ER-stress in the control of Simkania infection. Thus, Simkania forms extensive ER-SCV contact sites in host species evolutionary as diverse as human and amoeba. Moreover, Simkania is the first bacterial pathogen described to interfere with ER-stress induced signalling to promote infection.
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Affiliation(s)
- Adrian Mehlitz
- University of Wuerzburg, Biocenter, Department of Microbiology, Am Hubland, D-97074, Wuerzburg, Germany
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83
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Expression of prolyl 4-hydroxylase beta-polypeptide in non-small cell lung cancer treated with Chinese medicines. Chin J Integr Med 2014; 21:689-96. [PMID: 24382781 DOI: 10.1007/s11655-013-1535-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Indexed: 12/21/2022]
Abstract
OBJECTIVES To investigate the role of prolyl 4-hydroxylase beta polypeptide (P4HB) expressed in lung carcinoma and the intervention effect of Yiqi Chutan Formula (, YQCTF). METHODS Lung carcinoma model was established by subcutaneously inoculating LEWIS lung carcinoma cells in C57BL/6J mice. The differential expression of P4HB protein between the YQCTF (3.0 g/kg, gavage, once daily, 21 days) group and the control group was acquired by a 2 fluorescence difference gel electrophoresis (2D-DIGE), verified by Western blotting and identified by matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF/TOF-MS). The expression of P4HB and P4HB mRNA in cultured A549 cells from cisplatin (DDP) 1.5 µg/mL group and 15% serum combined with DDP 1.5 µg/mL group were detected by cellular immunohistochemistry and reverse transcription-polymerase chain reaction, respectively. RESULTS The proteomics research discovered that one-third of differential proteins including P4HB were decreased in the YQCTF group (P<0.01). Clinical pathology and tissue microarray studies showed that P4HB expression in lung cancer tissue was stronger than adjacent tissues and normal lung epithelial (P<0.01). In the YQCTF and DDP combined groups, the expression of P4HB and P4HB mRNA in A549 cell were decreased significantly (P<0.01). CONCLUSION YQCTF could inhibit the LEWIS lung carcinoma's growth, decrease the expression of P4HB in LEWIS lung carcinoma and A549 cells. YQCTF might take effect through regulating P4HB in endoplasmic reticulum to inhibit the incidence and growth process of lung carcinoma.
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84
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Abstract
The cell membrane is crucial for protection of the cell from its environment. MACPF/CDC proteins are a large superfamily known to be essential for bacterial pathogenesis and proper functioning of the immune system. The three most studied groups of MACPF/CDC proteins are cholesterol-dependent cytolysins from bacteria, the membrane attack complex of complement and human perforin. Their primary function is to form transmembrane pores in target cell membranes. The common mechanism of action comprises water-soluble monomeric proteins binding to the host cell membrane, oligomerization, and formation of a functional pore. This causes a disturbance in gradients of ions and other molecules across the membrane and can lead to cell death. Cells react to this form of attack in a complex manner. Responses can be general, like removing the perforated part of the membrane, or more specific, in many cases depending on binding of proteins to specific receptors to trigger various signalling cascades.
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85
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Seveau S. Multifaceted activity of listeriolysin O, the cholesterol-dependent cytolysin of Listeria monocytogenes. Subcell Biochem 2014; 80:161-95. [PMID: 24798012 DOI: 10.1007/978-94-017-8881-6_9] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The cholesterol-dependent cytolysins (CDCs) are a large family of pore-forming toxins that are produced by numerous Gram-positive bacterial pathogens. These toxins are released in the extracellular environment as water-soluble monomers or dimers that bind to cholesterol-rich membranes and assemble into large pore complexes. Depending upon their concentration, the nature of the host cell and membrane (cytoplasmic or intracellular) they target, the CDCs can elicit many different cellular responses. Among the CDCs, listeriolysin O (LLO), which is a major virulence factor of the facultative intracellular pathogen Listeria monocytogenes, is involved in several stages of the intracellular lifecycle of the bacterium and displays unique characteristics. It has long been known that following L. monocytogenes internalization into host cells, LLO disrupts the internalization vacuole, enabling the bacterium to replicate into the host cell cytosol. LLO is then used by cytosolic bacteria to spread from cell to cell, avoiding bacterial exposure to the extracellular environment. Although LLO is continuously produced during the intracellular lifecycle of L. monocytogenes, several processes limit its toxicity to ensure the survival of infected cells. It was previously thought that LLO activity was limited to mediating vacuolar escape during bacterial entry and cell to cell spreading. This concept has been challenged by compelling evidence suggesting that LLO secreted by extracellular L. monocytogenes perforates the host cell plasma membrane, triggering important host cell responses. This chapter provides an overview of the well-established intracellular activity of LLO and the multiple roles attributed to LLO secreted by extracellular L. monocytogenes.
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Affiliation(s)
- Stephanie Seveau
- Department of Microbiology, Department of Microbial Infection and Immunity, The Ohio State University, 484 West, 12th Avenue, Columbus, OH, 43210-1292, USA,
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86
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Smith JA, Khan M, Magnani DD, Harms JS, Durward M, Radhakrishnan GK, Liu YP, Splitter GA. Brucella induces an unfolded protein response via TcpB that supports intracellular replication in macrophages. PLoS Pathog 2013; 9:e1003785. [PMID: 24339776 PMCID: PMC3855547 DOI: 10.1371/journal.ppat.1003785] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 10/08/2013] [Indexed: 01/18/2023] Open
Abstract
Brucella melitensis is a facultative intracellular bacterium that causes brucellosis, the most prevalent zoonosis worldwide. The Brucella intracellular replicative niche in macrophages and dendritic cells thwarts immune surveillance and complicates both therapy and vaccine development. Currently, host-pathogen interactions supporting Brucella replication are poorly understood. Brucella fuses with the endoplasmic reticulum (ER) to replicate, resulting in dramatic restructuring of the ER. This ER disruption raises the possibility that Brucella provokes an ER stress response called the Unfolded Protein Response (UPR). In this study, B. melitensis infection up regulated expression of the UPR target genes BiP, CHOP, and ERdj4, and induced XBP1 mRNA splicing in murine macrophages. These data implicate activation of all 3 major signaling pathways of the UPR. Consistent with previous reports, XBP1 mRNA splicing was largely MyD88-dependent. However, up regulation of CHOP, and ERdj4 was completely MyD88 independent. Heat killed Brucella stimulated significantly less BiP, CHOP, and ERdj4 expression, but induced XBP1 splicing. Although a Brucella VirB mutant showed relatively intact UPR induction, a TcpB mutant had significantly compromised BiP, CHOP and ERdj4 expression. Purified TcpB, a protein recently identified to modulate microtubules in a manner similar to paclitaxel, also induced UPR target gene expression and resulted in dramatic restructuring of the ER. In contrast, infection with the TcpB mutant resulted in much less ER structural disruption. Finally, tauroursodeoxycholic acid, a pharmacologic chaperone that ameliorates the UPR, significantly impaired Brucella replication in macrophages. Together, these results suggest Brucella induces a UPR, via TcpB and potentially other factors, that enables its intracellular replication. Thus, the UPR may provide a novel therapeutic target for the treatment of brucellosis. These results also have implications for other intracellular bacteria that rely on host physiologic stress responses for replication.
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Affiliation(s)
- Judith A. Smith
- Department of Pediatrics, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, United States of America
| | - Mike Khan
- Cellular and Molecular Pathology Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Diogo D. Magnani
- Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine, Madison, Wisconsin, United States of America
| | - Jerome S. Harms
- Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine, Madison, Wisconsin, United States of America
| | - Marina Durward
- Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine, Madison, Wisconsin, United States of America
| | | | - Yi-Ping Liu
- Department of Pediatrics, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin, United States of America
| | - Gary A. Splitter
- Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine, Madison, Wisconsin, United States of America
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87
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Tsalikis J, Croitoru DO, Philpott DJ, Girardin SE. Nutrient sensing and metabolic stress pathways in innate immunity. Cell Microbiol 2013; 15:1632-41. [PMID: 23834352 DOI: 10.1111/cmi.12165] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 06/25/2013] [Accepted: 07/01/2013] [Indexed: 01/13/2023]
Abstract
Cells monitor nutrient availability through several highly conserved pathways that include the mTOR signalling axis regulated by AKT/PI3K, HIF and AMPK, as well as the GCN2/eIF2α integrated stress response pathway that provides cellular adaptation to amino acid starvation. Recent evidence has identified a critical interplay between these nutrient sensing pathways and innate immunity to bacterial pathogens, viruses and parasites. These observations suggest that, in addition to the well-characterized pro-inflammatory signalling mediated by pattern recognition molecules, a metabolic stress programme contributes to shape the global response to pathogens.
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Affiliation(s)
- Jessica Tsalikis
- Department of Laboratory Medicine and Pathobiologyy, University of Toronto, Toronto, M5S 1A8, Canada
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88
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Cassidy SKB, O'Riordan MXD. More than a pore: the cellular response to cholesterol-dependent cytolysins. Toxins (Basel) 2013; 5:618-36. [PMID: 23584137 PMCID: PMC3705283 DOI: 10.3390/toxins5040618] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 04/07/2013] [Accepted: 04/07/2013] [Indexed: 12/15/2022] Open
Abstract
Targeted disruption of the plasma membrane is a ubiquitous form of attack used in all three domains of life. Many bacteria secrete pore-forming proteins during infection with broad implications for pathogenesis. The cholesterol-dependent cytolysins (CDC) are a family of pore-forming toxins expressed predominately by Gram-positive bacterial pathogens. The structure and assembly of some of these oligomeric toxins on the host membrane have been described, but how the targeted cell responds to intoxication by the CDCs is not as clearly understood. Many CDCs induce lysis of their target cell and can activate apoptotic cascades to promote cell death. However, the extent to which intoxication causes cell death is both CDC- and host cell-dependent, and at lower concentrations of toxin, survival of intoxicated host cells is well documented. Additionally, the effect of CDCs can be seen beyond the plasma membrane, and it is becoming increasingly clear that these toxins are potent regulators of signaling and immunity, beyond their role in intoxication. In this review, we discuss the cellular response to CDC intoxication with emphasis on the effects of pore formation on the host cell plasma membrane and subcellular organelles and whether subsequent cellular responses contribute to the survival of the affected cell.
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Affiliation(s)
- Sara K B Cassidy
- Department of Microbiology and Immunology, University of Michigan Medical School, 1150 W. Medical Center Dr., Ann Arbor, MI 48109, USA.
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89
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Bischofberger M, Iacovache I, van der Goot FG. Pathogenic pore-forming proteins: function and host response. Cell Host Microbe 2013; 12:266-75. [PMID: 22980324 DOI: 10.1016/j.chom.2012.08.005] [Citation(s) in RCA: 146] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Organisms from all kingdoms produce pore-forming proteins, with the best-characterized being of bacterial origin. The last decade of research has revealed that the channels formed by these proteins can be very diverse, thus differentially affecting target cell-membrane permeability and consequent cellular outcome. The responses to these toxins are also extremely diverse due to multiple downstream effects of pore-induced changes in ion balance. Determining the secondary effects of pore-forming toxins is essential to understand their contribution to infection.
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Affiliation(s)
- Mirko Bischofberger
- Ecole Polytechnique Fédérale de Lausanne, Global Health Institute, Station 15, CH-1015 Lausanne, Switzerland
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90
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Abstract
By controlling gene expression at the level of mRNA translation, organisms temporally and spatially respond swiftly to an ever-changing array of environmental conditions. This capacity for rapid response is ideally suited for mobilizing host defenses and coordinating innate responses to infection. Not surprisingly, a growing list of pathogenic microbes target host mRNA translation for inhibition. Infection with bacteria, protozoa, viruses, and fungi has the capacity to interfere with ongoing host protein synthesis and thereby trigger and/or suppress powerful innate responses. This review discusses how diverse pathogens manipulate the host translation machinery and the impact of these interactions on infection biology and the immune response.
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Affiliation(s)
- Ian Mohr
- Department of Microbiology, NYU Cancer Institute, New York University School of Medicine, New York, NY 10016, USA
| | - Nahum Sonenberg
- Department of Biochemistry, Goodman Cancer Centre, McGill University, Montreal, QC H3A 1A3, Canada
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91
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Barel M, Meibom K, Dubail I, Botella J, Charbit A. Francisella tularensis regulates the expression of the amino acid transporter SLC1A5 in infected THP-1 human monocytes. Cell Microbiol 2012; 14:1769-83. [PMID: 22804921 DOI: 10.1111/j.1462-5822.2012.01837.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Revised: 07/03/2012] [Accepted: 07/06/2012] [Indexed: 01/14/2023]
Abstract
Francisella tularensis, a Gram-negative bacterium that causes the disease tularemia in a large number of animal species, is thought to reside preferentially within macrophages in vivo. F. tularensis has developed mechanisms to rapidly escape from the phagosome into the cytoplasm of infected cells, a habitat with a rich supply of nutrients, ideal for multiplication. SLC1A5 is a neutral amino acid transporter expressed by human cells, which serves, along with SLC7A5 to equilibrate cytoplasmic amino acid pools. We herein analysed whether SLC1A5 was involved in F. tularensis intracellular multiplication. We demonstrate that expression of SLC1A5 is specifically upregulated by F. tularensis in infected THP-1 human monocytes. Furthermore, we show that SLC1A5 downregulation decreases intracellular bacterial multiplication, supporting the involvement of SLC1A5 in F. tularensis infection. Notably, after entry of F. tularensis into cells and during the whole infection, the highly glycosylated form of SLC1A5 was deglycosylated only by bacteria capable of cytosolic multiplication. These data suggest that intracellular replication of F. tularensis depends on the function of host cell SLC1A5. Our results are the first, which show that Francisella intracellular multiplication in human monocyte cytoplasm is associated with a post-translational modification of a eukaryotic amino acid transporter.
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Affiliation(s)
- Monique Barel
- INSERM U1002, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
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92
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Martinon F. The endoplasmic reticulum: a sensor of cellular stress that modulates immune responses. Microbes Infect 2012; 14:1293-300. [PMID: 22800981 PMCID: PMC7110899 DOI: 10.1016/j.micinf.2012.07.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 07/03/2012] [Accepted: 07/04/2012] [Indexed: 12/25/2022]
Abstract
Many inflammatory and infectious diseases are characterized by the activation of signaling pathways steaming from the endoplasmic reticulum (ER). These pathways, primarily associated with loss of ER homeostasis, are emerging as key regulators of inflammation and infection. Recent advances shed light on the mechanisms linking ER-stress and immune responses.
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Affiliation(s)
- Fabio Martinon
- Dept. of Biochemistry, University of Lausanne, 155 Ch. Des Boveresses, Epalinges 1066, Switzerland.
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93
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Shrestha N, Bahnan W, Wiley DJ, Barber G, Fields KA, Schesser K. Eukaryotic initiation factor 2 (eIF2) signaling regulates proinflammatory cytokine expression and bacterial invasion. J Biol Chem 2012; 287:28738-44. [PMID: 22761422 DOI: 10.1074/jbc.m112.375915] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
In eukaryotic cells, there are two well characterized pathways that regulate translation initiation in response to stress, and each have been shown to be targeted by various viruses. We recently showed in a yeast-based model that the bacterial virulence factor YopJ disrupts one of these pathways, which is centered on the α-subunit of the translation factor eIF2. Here, we show in mammalian cells that induction of the eIF2 signaling pathway occurs following infection with bacterial pathogens and that, consistent with our yeast-based findings, YopJ reduces eIF2 signaling in response to endoplasmic reticulum stress, heavy metal toxicity, dsRNA, and bacterial infection. We demonstrate that the well documented activities of YopJ, inhibition of NF-κB activation and proinflammatory cytokine expression, are both dependent on an intact eIF2 signaling pathway. Unexpectedly, we found that cells with defective eIF2 signaling were more susceptible to bacterial invasion. This was true for pathogenic Yersinia, a facultative intracellular pathogen, as well as for the intracellular pathogens Listeria monocytogenes and Chlamydia trachomatis. Collectively, our data indicate that the highly conserved eIF2 signaling pathway, which is vitally important for antiviral responses, plays a variety of heretofore unrecognized roles in antibacterial responses.
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Affiliation(s)
- Niraj Shrestha
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, Florida 33136, USA
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94
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An IFN-γ-stimulated ATF6-C/EBP-β-signaling pathway critical for the expression of Death Associated Protein Kinase 1 and induction of autophagy. Proc Natl Acad Sci U S A 2012; 109:10316-21. [PMID: 22699507 DOI: 10.1073/pnas.1119273109] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The IFN family of cytokines operates a frontline defense against pathogens and neoplastic cells in vivo by controlling the expression of several genes. The death-associated protein kinase 1 (DAPK1), an IFN-γ-induced enzyme, controls cell cycle, apoptosis, autophagy, and tumor metastasis, and its expression is frequently down-regulated in a number of human tumors. Although the biochemical action of DAPK1 is well understood, mechanisms that regulate its expression are unclear. Previously, we have shown that transcription factor C/EBP-β is required for the basal and IFN-γ-induced expression of DAPK1. Here, we show that ATF6, an ER stress-induced transcription factor, interacts with C/EBP-β in an IFN-stimulated manner and is obligatory for Dapk1 expression. IFN-stimulated proteolytic processing of ATF6 and ERK1/2-mediated phosphorylation of C/EBP-β are necessary for these interactions. More importantly, IFN-γ failed to activate autophagic response in cells lacking either ATF6 or C/EBP-β. Consistent with these observations, the Atf6(-/-) mice were highly susceptible to lethal bacterial infections compared with the wild-type mice. These studies not only unravel an IFN signaling pathway that controls cell growth and antibacterial defense, but also expand the role of ATF6 beyond ER stress.
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95
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Hamon MA, Ribet D, Stavru F, Cossart P. Listeriolysin O: the Swiss army knife of Listeria. Trends Microbiol 2012; 20:360-8. [PMID: 22652164 DOI: 10.1016/j.tim.2012.04.006] [Citation(s) in RCA: 213] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2012] [Revised: 04/10/2012] [Accepted: 04/18/2012] [Indexed: 12/30/2022]
Abstract
Listeriolysin O (LLO) is a toxin produced by Listeria monocytogenes, an opportunistic bacterial pathogen responsible for the disease listeriosis. This disease starts with the ingestion of contaminated foods and mainly affects immunocompromised individuals, newborns, and pregnant women. In the laboratory, L. monocytogenes is used as a model organism to study processes such as cell invasion, intracellular survival, and cell-to-cell spreading, as this Gram-positive bacterium has evolved elaborate molecular strategies to subvert host cell functions. LLO is a major virulence factor originally shown to be crucial for bacterial escape from the internalization vacuole after entry into cells. However, recent studies are revisiting the role of LLO during infection and are revealing new insights into the action of LLO, in particular before bacterial entry. These latest findings along with their impact on the infectious process will be discussed.
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Affiliation(s)
- Mélanie Anne Hamon
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, Département de Biologie Cellulaire et Infection, F-75015 Paris, France
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96
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Affiliation(s)
- Chang-Hwa Song
- Department of Microbiology and Research Institute for Medical Sciences, College of Medicine, Chungnam National University, Daejeon, Korea
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