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Christ R, Siemes D, Zhao S, Widera L, Spangenberg P, Lill J, Thiebes S, Bottek J, Borgards L, Pinho AG, Silva NA, Monteiro S, Jorch SK, Gunzer M, Siebels B, Voss H, Schlüter H, Shevchuk O, Chen J, Engel DR. Inhibition of tumour necrosis factor alpha by Etanercept attenuates Shiga toxin-induced brain pathology. J Neuroinflammation 2025; 22:33. [PMID: 39920757 PMCID: PMC11804009 DOI: 10.1186/s12974-025-03356-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2024] [Accepted: 01/23/2025] [Indexed: 02/09/2025] Open
Abstract
Infection with enterohemorrhagic E. coli (EHEC) causes severe changes in the brain leading to angiopathy, encephalopathy and microglial activation. In this study, we investigated the role of tumour necrosis factor alpha (TNF-α) for microglial activation and brain pathology using a preclinical mouse model of EHEC infection. LC-MS/MS proteomics of mice injected with a combination of Shiga toxin (Stx) and lipopolysaccharide (LPS) revealed extensive alterations of the brain proteome, in particular enrichment of pathways involved in complement activation and coagulation cascades. Inhibition of TNF-α by the drug Etanercept strongly mitigated these changes, particularly within the complement pathway, suggesting TNF-α-dependent vasodilation and endothelial injury. Analysis of microglial populations using a novel human-in-the-loop deep learning algorithm for the segmentation of microscopic imaging data indicated specific morphological changes, which were reduced to healthy condition after inhibition of TNF-α. Moreover, the Stx/LPS-mediated angiopathy was significantly attenuated by inhibition of TNF-α. Overall, our findings elucidate the critical role of TNF-α in EHEC-induced brain pathology and highlight a potential therapeutic target for mitigating neuroinflammation, microglial activation and injury associated with EHEC infection.
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Affiliation(s)
- Robin Christ
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
| | - Devon Siemes
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
| | - Shuo Zhao
- Leibniz-Institut Für Analytische Wissenschaften, ISAS, E.V., Dortmund, Germany
| | - Lars Widera
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
| | - Philippa Spangenberg
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
| | - Julia Lill
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
| | - Stephanie Thiebes
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
| | - Jenny Bottek
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
| | - Lars Borgards
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
| | - Andreia G Pinho
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
- Life and Health Sciences Research Institute (ICVS),, School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Nuno A Silva
- Life and Health Sciences Research Institute (ICVS),, School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Susana Monteiro
- Life and Health Sciences Research Institute (ICVS),, School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's, PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Selina K Jorch
- Institute of Molecular Medicine and Experimental Immunology, University Hospital Bonn, Bonn, Germany
| | - Matthias Gunzer
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
- Leibniz-Institut Für Analytische Wissenschaften, ISAS, E.V., Dortmund, Germany
| | - Bente Siebels
- Section Mass Spectrometry and Proteomics, Diagnostic Center, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Hannah Voss
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
- Section Mass Spectrometry and Proteomics, Diagnostic Center, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Hartmut Schlüter
- Section Mass Spectrometry and Proteomics, Diagnostic Center, University Medical Center Hamburg-Eppendorf, 20246, Hamburg, Germany
| | - Olga Shevchuk
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany
| | - Jianxu Chen
- Leibniz-Institut Für Analytische Wissenschaften, ISAS, E.V., Dortmund, Germany
| | - Daniel R Engel
- Institute for Experimental Immunology and Imaging, University Hospital Essen, Essen, Germany.
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2
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Landoni VI, Pittaluga JR, Carestia A, Castillo LA, Nebel MDC, Martire-Greco D, Birnberg-Weiss F, Schattner M, Schierloh P, Fernández GC. Neutrophil Extracellular Traps Induced by Shiga Toxin and Lipopolysaccharide-Treated Platelets Exacerbate Endothelial Cell Damage. Front Cell Infect Microbiol 2022; 12:897019. [PMID: 35811684 PMCID: PMC9262415 DOI: 10.3389/fcimb.2022.897019] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 05/18/2022] [Indexed: 11/13/2022] Open
Abstract
Hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure in the pediatric population. The etiology of HUS is linked to Gram-negative, Shiga toxin (Stx)-producing enterohemorrhagic bacterial infections. While the effect of Stx is focused on endothelial damage of renal glomerulus, cytokines induced by Stx or bacterial lipopolysaccharide (LPS) and polymorphonuclear cells (PMNs) are involved in the development of the disease. PMN release neutrophil extracellular traps (NETs) to eliminate pathogens, although NETs favor platelets (Plts) adhesion/thrombus formation and can cause tissue damage within blood vessels. Since thrombus formation and occlusion of vessels are characteristic of HUS, PMN–Plts interaction in the context of Stx may promote netosis and contribute to the endothelial damage observed in HUS. The aim of this study was to determine the relevance of netosis induced by Stx in the context of LPS-sensitized Plts on endothelial damage. We observed that Stx2 induced a marked enhancement of netosis promoted by Plts after LPS stimulation. Several factors seemed to promote this phenomenon. Stx2 itself increased the expression of its receptor on Plts, increasing toxin binding. Stx2 also increased LPS binding to Plts. Moreover, Stx2 amplified LPS induced P-selectin expression on Plts and mixed PMN–Plts aggregates formation, which led to activation of PMN enhancing dramatically NETs formation. Finally, experiments revealed that endothelial cell damage mediated by PMN in the context of Plts treated with LPS and Stx2 was decreased when NETs were disrupted or when mixed aggregate formation was impeded using an anti-P-selectin antibody. Using a murine model of HUS, systemic endothelial damage/dysfunction was decreased when NETs were disrupted, or when Plts were depleted, indicating that the promotion of netosis by Plts in the context of LPS and Stx2 plays a fundamental role in endothelial toxicity. These results provide insights for the first time into the pivotal role of Plts as enhancers of endothelial damage through NETs promotion in the context of Stx and LPS. Consequently, therapies designed to reduce either the formation of PMN–Plts aggregates or NETs formation could lessen the consequences of endothelial damage in HUS.
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Affiliation(s)
- Verónica Inés Landoni
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Jose R. Pittaluga
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Agostina Carestia
- Laboratorio de Trombosis Experimental e Inmunobiología de la Inflamación, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Luis Alejandro Castillo
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Marcelo de Campos Nebel
- Laboratorio de Mutagénesis, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Daiana Martire-Greco
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Federico Birnberg-Weiss
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Mirta Schattner
- Laboratorio de Trombosis Experimental e Inmunobiología de la Inflamación, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
| | - Pablo Schierloh
- Instituto de Investigación y Desarrollo en Bioingeniería y Bioinformática, Centro Científico Tecnológico Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Santa Fe, Argentina
| | - Gabriela C. Fernández
- Laboratorio de Fisiología de los Procesos Inflamatorios, Instituto de Medicina Experimental (IMEX)-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)/Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires (CABA), Argentina
- *Correspondence: Gabriela C. Fernández, ;
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3
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Berdasco C, Duhalde Vega M, Rosato-Siri MV, Goldstein J. Environmental Cues Modulate Microglial Cell Behavior Upon Shiga Toxin 2 From Enterohemorrhagic Escherichia coli Exposure. Front Cell Infect Microbiol 2020; 9:442. [PMID: 31970091 PMCID: PMC6960108 DOI: 10.3389/fcimb.2019.00442] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 12/09/2019] [Indexed: 12/18/2022] Open
Abstract
Shiga toxin (Stx) produced by enterohemorrhagic E. coli produces hemolytic uremic syndrome and encephalopathies in patients, which can lead to either reversible or permanent neurological abnormalities, or even fatal cases depending on the degree of intoxication. It has been observed that the inflammatory component plays a decisive role in the severity of the disease. Therefore, the objective of this work was to evaluate the behavior of microglial cell primary cultures upon Stx2 exposure and heat shock or lipopolysaccharide challenges, as cues which modulate cellular environments, mimicking fever and inflammation states, respectively. In these contexts, activated microglial cells incorporated Stx2, increased their metabolism, phagocytic capacity, and pro-inflammatory profile. Stx2 uptake was associated to receptor globotriaosylceramide (Gb3)-pathway. Gb3 had three clearly distinguishable distribution patterns which varied according to different contexts. In addition, toxin uptake exhibited both a Gb3-dependent and a Gb3-independent binding depending on those contexts. Altogether, these results suggest a fundamental role for microglial cells in pro-inflammatory processes in encephalopathies due to Stx2 intoxication and highlight the impact of environmental cues.
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Affiliation(s)
- Clara Berdasco
- Laboratorio de Neurofisiopatología, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Medicina, Instituto de Fisiología y Biofísica "Houssay", Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Maite Duhalde Vega
- Instituto de Química y Fisicoquímica Biológicas, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
| | - María Victoria Rosato-Siri
- Instituto de Química y Fisicoquímica Biológicas, Universidad de Buenos Aires, CONICET, Buenos Aires, Argentina
| | - Jorge Goldstein
- Laboratorio de Neurofisiopatología, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Medicina, Instituto de Fisiología y Biofísica "Houssay", Universidad de Buenos Aires, Buenos Aires, Argentina
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Ozuru R, Wakao S, Tsuji T, Ohara N, Matsuba T, Amuran MY, Isobe J, Iino M, Nishida N, Matsumoto S, Iwadate K, Konishi N, Yasuda K, Tashiro K, Hida M, Yadoiwa A, Kato S, Yamashita E, Matsumoto S, Kurozawa Y, Dezawa M, Fujii J. Rescue from Stx2-Producing E. coli-Associated Encephalopathy by Intravenous Injection of Muse Cells in NOD-SCID Mice. Mol Ther 2020; 28:100-118. [PMID: 31607541 PMCID: PMC6953779 DOI: 10.1016/j.ymthe.2019.09.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 09/11/2019] [Accepted: 09/26/2019] [Indexed: 12/17/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) causes hemorrhagic colitis, hemolytic uremic syndrome, and acute encephalopathies that may lead to sudden death or severe neurologic sequelae. Current treatments, including immunoglobulin G (IgG) immunoadsorption, plasma exchange, steroid pulse therapy, and the monoclonal antibody eculizumab, have limited effects against the severe neurologic sequelae. Multilineage-differentiating stress-enduring (Muse) cells are endogenous reparative non-tumorigenic stem cells that naturally reside in the body and are currently under clinical trials for regenerative medicine. When administered intravenously, Musecells accumulate to the damaged tissue, where they exert anti-inflammatory, anti-apoptotic, anti-fibrotic, and immunomodulatory effects, and replace damaged cells by differentiating into tissue-constituent cells. Here, severely immunocompromised non-obese diabetic/severe combined immunodeficiency (NOD-SCID) mice orally inoculated with 9 × 109 colony-forming units of STEC O111 and treated 48 h later with intravenous injection of 5 × 104 Muse cells exhibited 100% survival and no severe after-effects of infection. Suppression of granulocyte-colony-stimulating factor (G-CSF) by RNAi abolished the beneficial effects of Muse cells, leading to a 40% death and significant body weight loss, suggesting the involvement of G-CSF in the beneficial effects of Muse cells in STEC-infected mice. Thus, intravenous administration of Muse cells could be a candidate therapeutic approach for preventing fatal encephalopathy after STEC infection.
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Affiliation(s)
- Ryo Ozuru
- Division of Bacteriology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
| | - Shohei Wakao
- Department of Stem Cell Biology and Histology, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan
| | - Takahiro Tsuji
- Division of Bacteriology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
| | - Naoya Ohara
- Department of Oral Microbiology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8525, Japan
| | - Takashi Matsuba
- Division of Bacteriology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
| | - Muhammad Yunus Amuran
- Department of Neurology, Hasanuddin University Faculty of Medicine, Makassar 90245, Indonesia
| | - Junko Isobe
- Department of Bacteriology, Toyama Institute of Health, Imizu, Toyama 939-0363, Japan
| | - Morio Iino
- Division of Legal Medicine, Department of Social Medicine, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
| | - Naoki Nishida
- Department of Legal Medicine, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama 930-0194, Japan
| | - Sari Matsumoto
- Department of Forensic Medicine, The Jikei University School of Medicine, Nishi-shimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Kimiharu Iwadate
- Department of Forensic Medicine, The Jikei University School of Medicine, Nishi-shimbashi, Minato-ku, Tokyo 105-8461, Japan
| | - Noriko Konishi
- Department of Food Microbiology, Tokyo Metropolitan Institute of Public, Tokyo 169-0073, Japan
| | - Kaori Yasuda
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan
| | - Kosuke Tashiro
- Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan
| | - Misato Hida
- Division of Bacteriology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
| | - Arisato Yadoiwa
- Division of Bacteriology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
| | - Shinsuke Kato
- Division of Neuropathology, Department of Brain and Neuroscience, Faculty of Medicine, School of Medicine, Tottori University Faculty of Medicine, Yonago 683-8503, Japan
| | - Eijiro Yamashita
- Division of Clinical Radiology, Tottori University Hospital, Yonago 683-8504, Japan
| | - Sohkichi Matsumoto
- Department of Bacteriology, Niigata University School of Medicine, Niigata 951-8510, Japan
| | - Yoichi Kurozawa
- Division of Health Administration and Promotion, Department of Social Medicine, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan
| | - Mari Dezawa
- Department of Stem Cell Biology and Histology, Graduate School of Medicine, Tohoku University, Sendai 980-8575, Japan
| | - Jun Fujii
- Division of Bacteriology, Department of Microbiology and Immunology, Faculty of Medicine, Tottori University, Yonago 683-8503, Japan.
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Lafalla Manzano AF, Gil Lorenzo AF, Bocanegra V, Costantino VV, Cacciamani V, Benardon ME, Vallés PG. Rab7b participation on the TLR4 (Toll-like receptor) endocytic pathway in Shiga toxin-associated Hemolytic Uremic Syndrome (HUS). Cytokine 2019; 121:154732. [PMID: 31153054 DOI: 10.1016/j.cyto.2019.05.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 05/14/2019] [Accepted: 05/19/2019] [Indexed: 01/07/2023]
Abstract
BACKGROUND The inflammatory response of the host to Shiga toxin and/or lipopolysaccharide (LPS) of Escherichia coli (E. coli) is included in (HUS). The TLR4-LPS complex is internalized and TLR4 induced inflammatory signaling is stopped by targeting the complex for degradation. Rab7b, a small guanosine triphosphatase (GTPase) expressed in monocytes, regulates the later stages of the endocytic pathway. OBJECTIVE we studied the Rab7b participation on the TLR4 endocytic pathway and its effect on monocyte cytokine production along the acute course of pediatric Shiga toxin-associated HUS. METHODS AND RESULTS Monocytes were identified according to their positivity in CD14 expression. Surface TLR4 expression in monocytes from 18 HUS patients significantly increased by day 1 to 6, showing the highest increase on day 4 compared to monocytes of 10 healthy children. Significant higher surface TLR4 expression was accompanied by increased proinflammatory intracellular cytokines, tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). In contrast, after these time points, surface TLR4 expression and intracellular TNF-α levels, returned to near control levels after 10 days. Furthermore, confocal immunofluorescence microscopy proved colocalization of increased intracellular TLR4/Rab7b determined by Pearson's coefficient in monocytes from HUS patients from day 1 on the highest colocalization of both proteins by day 4. Decreased TLR4/Rab7b colocalization was shown 10 days after HUS onset. CONCLUSION The colocalization of TLR4 and Rab7b allows us to suggest Rab7b participation in the control of the TLR4 endocytic pathway in HUS patient monocytes. A consequential fall in cytokine production throughout the early follow up of HUS is demonstrated.
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Affiliation(s)
| | - Andrea Fernanda Gil Lorenzo
- Área de Fisiopatología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Victoria Bocanegra
- IMBECU-CONICET (Instituto de Medicina y Biología Experimental de Cuyo - Consejo Nacional de Investigaciones Científicas y Técnicas), Argentina
| | - Valeria Victoria Costantino
- IMBECU-CONICET (Instituto de Medicina y Biología Experimental de Cuyo - Consejo Nacional de Investigaciones Científicas y Técnicas), Argentina
| | - Valeria Cacciamani
- IMBECU-CONICET (Instituto de Medicina y Biología Experimental de Cuyo - Consejo Nacional de Investigaciones Científicas y Técnicas), Argentina
| | - María Eugenia Benardon
- Área de Fisiopatología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Patricia G Vallés
- Área de Fisiopatología, Departamento de Patología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina; IMBECU-CONICET (Instituto de Medicina y Biología Experimental de Cuyo - Consejo Nacional de Investigaciones Científicas y Técnicas), Argentina; Hospital Pediátrico Humberto J. Notti, Servicio de Nefrología, Ministerio de Salud, Mendoza, Argentina.
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6
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Lee MS, Tesh VL. Roles of Shiga Toxins in Immunopathology. Toxins (Basel) 2019; 11:E212. [PMID: 30970547 PMCID: PMC6521259 DOI: 10.3390/toxins11040212] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 04/04/2019] [Accepted: 04/05/2019] [Indexed: 12/20/2022] Open
Abstract
Shigella species and Shiga toxin-producing Escherichia coli (STEC) are agents of bloody diarrhea that may progress to potentially lethal complications such as diarrhea-associated hemolytic uremic syndrome (D+HUS) and neurological disorders. The bacteria share the ability to produce virulence factors called Shiga toxins (Stxs). Research over the past two decades has identified Stxs as multifunctional toxins capable of inducing cell stress responses in addition to their canonical ribotoxic function inhibiting protein synthesis. Notably, Stxs are not only potent inducers of cell death, but also activate innate immune responses that may lead to inflammation, and these effects may increase the severity of organ injury in patients infected with Stx-producing bacteria. In the intestines, kidneys, and central nervous system, excessive or uncontrolled host innate and cellular immune responses triggered by Stxs may result in sensitization of cells to toxin mediated damage, leading to immunopathology and increased morbidity and mortality in animal models (including primates) and human patients. Here, we review studies describing Stx-induced innate immune responses that may be associated with tissue damage, inflammation, and complement activation. We speculate on how these processes may contribute to immunopathological responses to the toxins.
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Affiliation(s)
- Moo-Seung Lee
- Environmental Diseases Research Center, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahak-ro, Daejeon 34141, Korea.
- Department of Biomolecular Science, KRIBB School of Bioscience, Korea University of Science and Technology (UST), 127 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea.
| | - Vernon L Tesh
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77807, USA.
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Abstract
Enterohemorrhagic Escherichia coli (EHEC) is a highly pathogenic bacterial strain capable of causing watery or bloody diarrhea, the latter termed hemorrhagic colitis, and hemolytic-uremic syndrome (HUS). HUS is defined as the simultaneous development of non-immune hemolytic anemia, thrombocytopenia, and acute renal failure. The mechanism by which EHEC bacteria colonize and cause severe colitis, followed by renal failure with activated blood cells, as well as neurological symptoms, involves the interaction of bacterial virulence factors and specific pathogen-associated molecular patterns with host cells as well as the host response. The innate immune host response comprises the release of antimicrobial peptides as well as cytokines and chemokines in addition to activation and/or injury to leukocytes, platelets, and erythrocytes and activation of the complement system. Some of the bacterial interactions with the host may be protective in nature, but, when excessive, contribute to extensive tissue injury, inflammation, and thrombosis, effects that may worsen the clinical outcome of EHEC infection. This article describes aspects of the host response occurring during EHEC infection and their effects on specific organs.
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8
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Angel Villegas N, Baronetti J, Albesa I, Etcheverría A, Becerra MC, Padola NL, Paraje MG. Effect of antibiotics on cellular stress generated in Shiga toxin-producing Escherichia coli O157:H7 and non-O157 biofilms. Toxicol In Vitro 2015; 29:1692-700. [PMID: 26130220 DOI: 10.1016/j.tiv.2015.06.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 06/25/2015] [Accepted: 06/26/2015] [Indexed: 11/28/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) are important food-borne pathogens, with the main virulence factor of this bacterium being its capacity to secrete Shiga toxins (Stxs). Therefore, the use of certain antibiotics for the treatment of this infection, which induces the liberation of Stxs, is controversial. Reactive oxygen and nitrogen species are also involved in the pathogenesis of different diseases. The purpose of this study was to analyze the effects of antibiotics on biofilms of STEC and the relationships between cellular stress and the release of Stx. To this end, biofilms of reference and clinical strains were treated with antibiotics (ciprofloxacin, fosfomycin and rifaximin) and the production of oxidants, the antioxidant defense system and toxin release were evaluated. Ciprofloxacin altered the prooxidant-antioxidant balance, with a decrease of oxidant metabolites and an increase of superoxide dismutase and catalase activity, being associated with high-levels of Stx production. Furthermore, inhibition of oxidative stress by exogenous antioxidants was correlated with a reduction in the liberation of Stx, indicating the participation of this phenomenon in the release of this toxin. In contrast, fosfomycin and rifaximin produced less alteration with a minimal production of Stx. Our data show that treatment of biofilm-STEC with these antibiotics induces oxidative stress-mediated release of Stx.
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Affiliation(s)
- Natalia Angel Villegas
- IMBIV-CONICET y Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - José Baronetti
- IMBIV-CONICET y Cátedra de Microbiología, Facultad de Ciencias Exactas Físicas y Naturales, Universidad Nacional de Córdoba, Argentina
| | - Inés Albesa
- IMBIV-CONICET y Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - Analía Etcheverría
- Laboratorio de Inmunoquímica y Biotecnología, Dpto. SAMP, Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires, Tandil, Argentina
| | - M Cecilia Becerra
- IMBIV-CONICET y Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | - Nora L Padola
- Laboratorio de Inmunoquímica y Biotecnología, Dpto. SAMP, Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires, Tandil, Argentina
| | - M Gabriela Paraje
- IMBIV-CONICET y Cátedra de Microbiología, Facultad de Ciencias Exactas Físicas y Naturales, Universidad Nacional de Córdoba, Argentina.
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9
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Shiga toxin-2 enhances heat-shock-induced apoptotic cell death in cultured and primary glial cells. Cell Biol Toxicol 2014; 30:289-99. [PMID: 25200685 DOI: 10.1007/s10565-014-9286-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 09/01/2014] [Indexed: 01/07/2023]
Abstract
The blood-brain barrier (BBB) selectively controls the homeostasis of the central nervous system (CNS) environment using specific structural and biochemical features of the endothelial cells, pericytes, and glial limitans. Glial cells, which represent the cellular components of the mature BBB, are the most numerous cells in the brain and are indispensable for neuronal functioning. We investigated the effects of Shiga toxin on glial cells in vitro. Shiga toxin failed to inhibit cell proliferation but attenuated expression of heat shock protein 70, which is one of the chaperone proteins, in cultured and primary glial cells. Furthermore, the combination of Shiga toxin and a heat shock procedure induced cell apoptosis and decreased cell proliferation in both cells. Thus, we speculate that glial cell death in response to the combination of Shiga toxin and heat shock might weaken the BBB and induce central nervous system complications.
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Relevance of biofilms in the pathogenesis of Shiga-toxin-producing Escherichia coli infection. ScientificWorldJournal 2013; 2013:607258. [PMID: 24324376 PMCID: PMC3845835 DOI: 10.1155/2013/607258] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 09/25/2013] [Indexed: 11/17/2022] Open
Abstract
The present study was designed to determine the relationships among biofilm formation, cellular stress and release of Shiga toxin (Stx) by three different clinical Shiga toxin-producing Escherichia coli (STEC) strains. The biofilm formation was determined using crystal violet stain in tryptic soy broth or thioglycollate medium with the addition of sugars (glucose or mannose) or hydrogen peroxide. The reactive oxygen species (ROSs) were detected by the reduction of nitro blue tetrazolium and reactive nitrogen intermediates (RNI) determined by the Griess assay. In addition, the activities of two antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT), were studied. For the cytotoxicity studies, Vero cells were cultured with Stx released of STEC biofilms. The addition of sugars in both culture mediums resulted in an increase in biofilm biomass, with a decrease in ROS and RNI production, low levels of SOD and CAT activity, and minimal cytotoxic effects. However, under stressful conditions, an important increase in the antioxidant enzyme activity and high level of Stx production were observed. The disturbance in the prooxidant-antioxidant balance and its effect on the production and release of Stx evaluated under different conditions of biofilm formation may contribute to a better understanding of the relevance of biofilms in the pathogenesis of STEC infection.
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Burdet J, Sacerdoti F, Cella M, Franchi AM, Ibarra C. Role of TNF-α in the mechanisms responsible for preterm delivery induced by Stx2 in rats. Br J Pharmacol 2013; 168:946-53. [PMID: 23043728 PMCID: PMC3631382 DOI: 10.1111/j.1476-5381.2012.02239.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 08/22/2012] [Accepted: 09/06/2012] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Infections with a strain of Escherichia coli producing Shiga toxins could be one of the causes of fetal morbidity and mortality in pregnant women. We have previously reported that Shiga toxin type 2 (Stx2) induces preterm delivery in pregnant rats. In this study, we evaluate the role of TNF-α, PGs and NO in the Stx2-induced preterm delivery. EXPERIMENTAL APPROACH Pregnant rats were treated with Stx2 (0.7 ng g(-1)) and killed at different times after treatment. Placenta and decidua were used to analyse NOS activity by the conversion of L-[(14)C]arginine into L-[(14)C]citrulline, levels of PGE(2) and PGF(2α) assessed by radioimmunoassay, and cyclooxygenase (COX) proteins by Western blot. TNF-α level was analysed in serum by ELISA and by cytotoxicity in L929 cells. The inhibitor of inducible NOS, aminoguanidine, the COX-2 inhibitor, meloxicam, and the competitive inhibitor of TNF-α, etanercept, were used alone or combined to inhibit NO, PGs and TNF-α production respectively, to prevent Stx2-induced preterm delivery. KEY RESULTS Stx2 increased placental PGE(2) and decidual PGF(2α) levels as well as COX-2 expression in both tissues. Aminoguanidine and meloxicam delayed the preterm delivery time but did not prevent it. Etanercept blocked the TNF-α increase after Stx2 treatment and reduced the preterm delivery by approximately 30%. The combined action of aminoguanidine and etanercept prevented Stx2-induced preterm delivery by roughly 70%. CONCLUSION AND IMPLICATIONS Our results demonstrate that the increased TNF-α and NO induced by Stx2 were the predominant factors responsible for preterm delivery in rats.
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Affiliation(s)
- Juliana Burdet
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos AiresBuenos Aires, Argentina
| | - Flavia Sacerdoti
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos AiresBuenos Aires, Argentina
| | - Maximiliano Cella
- Centro de Estudios Farmacológicos y Botánicos (CEFYBO-CONICET), Universidad de Buenos AiresBuenos Aires, Argentina
| | - Ana M Franchi
- Centro de Estudios Farmacológicos y Botánicos (CEFYBO-CONICET), Universidad de Buenos AiresBuenos Aires, Argentina
| | - Cristina Ibarra
- Laboratorio de Fisiopatogenia, Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos AiresBuenos Aires, Argentina
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Chemokine expression in human astrocytes in response to shiga toxin 2. Int J Inflam 2012; 2012:135803. [PMID: 23304632 PMCID: PMC3529876 DOI: 10.1155/2012/135803] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Revised: 11/07/2012] [Accepted: 11/07/2012] [Indexed: 12/11/2022] Open
Abstract
Infection with Shiga toxin- (Stx-) producing Escherichia coli can lead to hemolytic uremic syndrome (HUS). Approximately, 30% of patients with HUS suffer from complications in the central nervous system (CNS), which is an important determinant of mortality in such patients. Autopsy shows mostly edema and hypoxic-ischemic changes in the CNS, often with microhemorrhages. It has been suggested that Stx-induced damage to human brain endothelial cells, which are essential constituents of the blood-brain barrier, plays a crucial role in the development of the CNS complications. However, it is unclear whether Stx affects brain neuroglial cells. In the present study, we investigated the direct involvement of Stx in the inflammatory responses of human astrocytes (HASTs) treated with Stx. Immunohistochemistry and real-time PCR revealed that the expression of globotriaosylceramide (Gb3), the receptor for Stx2, and Gb3 synthase (GalT6) in HASTs was increased by interleukin-1β (IL-1β). Expression of both interleukin-8 (IL-8) and monocyte chemoattractant protein-1 (MCP-1) mRNA in HASTs was significantly upregulated by Stx2. These results suggest that Stx2 induces inflammatory responses, particularly through expression of chemokines, in HASTs expressing Gb3 and may, thus, affect brain glial cells, playing a key role in the pathogenesis of CNS manifestations associated with HUS.
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Mayer CL, Leibowitz CS, Kurosawa S, Stearns-Kurosawa DJ. Shiga toxins and the pathophysiology of hemolytic uremic syndrome in humans and animals. Toxins (Basel) 2012; 4:1261-87. [PMID: 23202315 PMCID: PMC3509707 DOI: 10.3390/toxins4111261] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 11/01/2012] [Accepted: 11/02/2012] [Indexed: 12/25/2022] Open
Abstract
Food-borne diseases are estimated at 76 million illnesses and 5000 deaths every year in the United States with the greatest burden on young children, the elderly and immunocompromised populations. The impact of efficient food distribution systems and a truly global food supply ensures that outbreaks, previously sporadic and contained locally, are far more widespread and emerging pathogens have far more frequent infection opportunities. Enterohemorrhagic E. coli is an emerging food- and water-borne pathogen family whose Shiga-like toxins induce painful hemorrhagic colitis with potentially lethal complications of hemolytic uremic syndrome (HUS). The clinical manifestations of Shiga toxin-induced HUS overlap with other related syndromes yet molecular mechanisms differ considerably. As discussed herein, understanding these differences and the novel properties of the toxins is imperative for clinical management decisions, design of appropriate animal models, and choices of adjunctive therapeutics. The emergence of new strains with rapidly aggressive virulence makes clinical and research initiatives in this field a high public health priority.
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Affiliation(s)
- Chad L Mayer
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, MA 02118, USA.
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Lucero MS, Mirarchi F, Goldstein J, Silberstein C. Intraperitoneal administration of Shiga toxin 2 induced neuronal alterations and reduced the expression levels of aquaporin 1 and aquaporin 4 in rat brain. Microb Pathog 2012; 53:87-94. [PMID: 22610042 DOI: 10.1016/j.micpath.2012.05.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Revised: 05/03/2012] [Accepted: 05/10/2012] [Indexed: 11/28/2022]
Abstract
Shiga toxin-producing Escherichia coli produces watery and hemorrhagic diarrhea, and hemolytic uremic syndrome (HUS) characterized by thrombocytopenia, microangiopathic hemolytic anemia, and acute renal failure. Central nervous system (CNS) complications are observed in around 30% of infant population with HUS. Common signs of severe CNS involvement leading to death include seizures, alteration of consciousness, hemiparesis, visual disturbances, and brain stem symptoms. The purpose of the present work was to study the effects of Shiga toxin 2 (Stx2) in the brain of rats intraperitoneally (i.p.) injected with a supernatant from recombinant E. coli expressing Stx2 (sStx2). Neurological alterations such as postural and motor abnormalities including lethargy, abnormal walking, and paralysis of hind legs, were observed in this experimental model of HUS in rats. Neuronal damage, as well as significant decrease in aquaporin 1 (AQP1) and aquaporin 4 (AQP4) expression levels were observed in the brain of rats, 2 days after sStx2 injection, compared to controls. Downregulation of aquaporin protein levels, and neuronal alterations, observed in brain of rats injected with sStx2, may be involved in edema formation and in neurological manifestations characteristic of HUS.
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Affiliation(s)
- María Soledad Lucero
- Departamento de Fisiología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
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Enterohemorrhagic Escherichia coli O157:H7 Shiga toxins inhibit gamma interferon-mediated cellular activation. Infect Immun 2012; 80:2307-15. [PMID: 22526675 DOI: 10.1128/iai.00255-12] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 is a food-borne pathogen that causes significant morbidity and mortality in developing and industrialized nations. EHEC infection of host epithelial cells is capable of inhibiting the gamma interferon (IFN-γ) proinflammatory pathway through the inhibition of Stat-1 phosphorylation, which is important for host defense against microbial pathogens. The aim of this study was to determine the bacterial factors involved in the inhibition of Stat-1 tyrosine phosphorylation. Human HEp-2 and Caco-2 epithelial cells were challenged directly with either EHEC or bacterial culture supernatants and stimulated with IFN-γ, and then the protein extracts were analyzed by immunoblotting. The data showed that IFN-γ-mediated Stat-1 tyrosine phosphorylation was inhibited by EHEC secreted proteins. Using two-dimensional difference gel electrophoresis, EHEC Shiga toxins were identified as candidate inhibitory factors. EHEC Shiga toxin mutants were then generated and complemented in trans, and mutant culture supernatant was supplemented with purified Stx to confirm their ability to subvert IFN-γ-mediated cell activation. We conclude that while other factors are likely involved in the suppression of IFN-γ-mediated Stat-1 tyrosine phosphorylation, E. coli-derived Shiga toxins represent a novel mechanism by which EHEC evades the host immune system.
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Shiga toxin 1 induces on lipopolysaccharide-treated astrocytes the release of tumor necrosis factor-alpha that alter brain-like endothelium integrity. PLoS Pathog 2012; 8:e1002632. [PMID: 22479186 PMCID: PMC3315494 DOI: 10.1371/journal.ppat.1002632] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2011] [Accepted: 02/23/2012] [Indexed: 01/09/2023] Open
Abstract
The hemolytic uremic syndrome (HUS) is characterized by hemolytic anemia, thrombocytopenia and renal dysfunction. The typical form of HUS is generally associated with infections by Gram-negative Shiga toxin (Stx)-producing Escherichia coli (STEC). Endothelial dysfunction induced by Stx is central, but bacterial lipopolysaccharide (LPS) and neutrophils (PMN) contribute to the pathophysiology. Although renal failure is characteristic of this syndrome, neurological complications occur in severe cases and is usually associated with death. Impaired blood-brain barrier (BBB) is associated with damage to cerebral endothelial cells (ECs) that comprise the BBB. Astrocytes (ASTs) are inflammatory cells in the brain and determine the BBB function. ASTs are in close proximity to ECs, hence the study of the effects of Stx1 and LPS on ASTs, and the influence of their response on ECs is essential. We have previously demonstrated that Stx1 and LPS induced activation of rat ASTs and the release of inflammatory factors such as TNF-α, nitric oxide and chemokines. Here, we demonstrate that rat ASTs-derived factors alter permeability of ECs with brain properties (HUVECd); suggesting that functional properties of BBB could also be affected. Additionally, these factors activate HUVECd and render them into a proagregant state promoting PMN and platelets adhesion. Moreover, these effects were dependent on ASTs secreted-TNF-α. Stx1 and LPS-induced ASTs response could influence brain ECs integrity and BBB function once Stx and factors associated to the STEC infection reach the brain parenchyma and therefore contribute to the development of the neuropathology observed in HUS. Hemolytic-uremic syndrome (HUS) is generally caused by Shiga toxin (Stx)-producing Escherichia coli but bacterial lipopolysaccharide (LPS) and neutrophils (PMN) contribute to the pathophysiology. Acute renal failure is the main feature of HUS, but in severe cases, patients develop neurological complications, which are usually associated with death. Although the mechanisms of neurological damage remain uncertain, alterations/injury of brain endothelial cells (ECs) which constitute the blood-brain barrier (BBB) is clear. Astrocytes (ASTs) are inflammatory cells enclosing ECs and are responsible of the normal function of the barrier. We have recently demonstrated that Stx1, one of the most common types of Stx, induce an inflammatory response in LPS-treated ASTs. We then study the effects of factors released by ASTs in response to LPS and/or Stx1 on brain-like ECs. We demonstrate that Stx1 induces in LPS-treated ASTs the release of factors that alter brain properties in ECs, including the permeability; turning them more susceptible to Stx1 toxic effects. Furthermore, they activate ECs, neutrophils (PMN) and platelets and render ECs into a proagregant state promoting PMN and platelet adhesion. Our results suggest that ASTs could influence brain ECs integrity and BBB function once Stx in combination with bacterial factors reach the brain parenchyma.
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Toll-like receptor 4 expression on circulating leucocytes in hemolytic uremic syndrome. Pediatr Nephrol 2012; 27:407-15. [PMID: 21969092 DOI: 10.1007/s00467-011-2014-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2011] [Revised: 08/21/2011] [Accepted: 09/06/2011] [Indexed: 12/26/2022]
Abstract
Lipopolysaccharide stimulation of toll-like receptor 4 (TLR4) activates signal transduction pathways leading to proinflammatory cytokine secretion. We investigated TLR4 surface receptor expression on peripheral blood neutrophils and monocytes and their ability to modulate inflammatory cytokine release in 15 patients 1, 3, and 10 days after hemolytic uremic syndrome (HUS) onset. Seven patients with Escherichia coli (EHEC)-associated diarrhea and seven healthy controls were also studied. Isolated leucocytes from HUS-onset patients exhibited significantly higher messenger RNA (mRNA) TLR4 expression than controls. Moreover, TLR4 protein expression on neutrophils, determined by flow cytometry, was upregulated, driving dependent proinflammatory cytokine, tumor necrosis factor alpha (TNF-α), and interleukin 8 (IL-8) increase, and decreased anti-inflammatory IL-10 release at HUS onset compared with patients with EHEC diarrhea and controls. TLR4 expression on neutrophils was positively correlated with serum TNF-α levels. Conversely, significant reduction of neutrophil TLR4 receptor expression and lack of cytokine-responsive element activation was shown in patients 3 and 10 days after HUS onset. No differences were demonstrated in TLR4 receptor expression on monocytes among the studied groups. Our results suggest TLR4 expression may be differently regulated on neutrophils and monocytes. They could be dynamically modulated across the early development of HUS on neutrophils, resulting in negative regulation preceded by TLR4 overactivation.
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Obrig TG. Escherichia coli Shiga Toxin Mechanisms of Action in Renal Disease. Toxins (Basel) 2010; 2:2769-2794. [PMID: 21297888 PMCID: PMC3032420 DOI: 10.3390/toxins2122769] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 11/13/2010] [Accepted: 11/24/2010] [Indexed: 02/06/2023] Open
Abstract
Shiga toxin-producing Escherichia coli is a contaminant of food and water that in humans causes a diarrheal prodrome followed by more severe disease of the kidneys and an array of symptoms of the central nervous system. The systemic disease is a complex referred to as diarrhea-associated hemolytic uremic syndrome (D(+)HUS). D(+)HUS is characterized by thrombocytopenia, microangiopathic hemolytic anemia, and acute renal failure. This review focuses on the renal aspects of D(+)HUS. Current knowledge of this renal disease is derived from a combination of human samples, animal models of D(+)HUS, and interaction of Shiga toxin with isolated renal cell types. Shiga toxin is a multi-subunit protein complex that binds to a glycosphingolipid receptor, Gb3, on select eukaryotic cell types. Location of Gb3 in the kidney is predictive of the sites of action of Shiga toxin. However, the toxin is cytotoxic to some, but not all cell types that express Gb3. It also can cause apoptosis or generate an inflammatory response in some cells. Together, this myriad of results is responsible for D(+)HUS disease.
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Affiliation(s)
- Tom G Obrig
- Department of Microbiology and Immunology, School of Medicine, University of Maryland, 685 W. Baltimore St., HSF I Suite 380, Baltimore, MD 21201, USA; ; Tel.: +1-410-706-6917
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