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Scasny A, Alibayov B, Khan F, Rao SJ, Murin L, Jop Vidal AG, Smith P, Li W, Edwards K, Warncke K, Vidal JE. Oxidation of hemoproteins by Streptococcus pneumoniae collapses the cell cytoskeleton and disrupts mitochondrial respiration leading to the cytotoxicity of human lung cells. Microbiol Spectr 2024; 12:e0291223. [PMID: 38084982 PMCID: PMC10783075 DOI: 10.1128/spectrum.02912-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 11/06/2023] [Indexed: 12/21/2023] Open
Abstract
IMPORTANCE Streptococcus pneumoniae (Spn) colonizes the lungs, killing millions every year. During its metabolism, Spn produces abundant amounts of hydrogen peroxide. When produced in the lung parenchyma, Spn-hydrogen peroxide (H2O2) causes the death of lung cells, and details of the mechanism are studied here. We found that Spn-H2O2 targets intracellular proteins, resulting in the contraction of the cell cytoskeleton and disruption of mitochondrial function, ultimately contributing to cell death. Intracellular proteins targeted by Spn-H2O2 included cytochrome c and, surprisingly, a protein of the cell cytoskeleton, beta-tubulin. To study the details of oxidative reactions, we used, as a surrogate model, the oxidation of another hemoprotein, hemoglobin. Using the surrogate model, we specifically identified a highly reactive radical whose creation was catalyzed by Spn-H2O2. In sum, we demonstrated that the oxidation of intracellular targets by Spn-H2O2 plays an important role in the cytotoxicity caused by Spn, thus providing new targets for interventions.
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Affiliation(s)
- Anna Scasny
- Department of Cell and Molecular Biology, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Center for Immunology and Microbial Research, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Babek Alibayov
- Department of Cell and Molecular Biology, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Center for Immunology and Microbial Research, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Faidad Khan
- Department of Cell and Molecular Biology, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Center for Immunology and Microbial Research, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Shambavi J. Rao
- Department of Otolaryngology-Head and Neck Surgery, The Ohio State School of Medicine, The Ohio State Wexner Medical Center, Columbus, Ohio, USA
| | - Landon Murin
- Department of Cell and Molecular Biology, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Center for Immunology and Microbial Research, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Ana G. Jop Vidal
- Department of Cell and Molecular Biology, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Center for Immunology and Microbial Research, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Perriann Smith
- Mississippi INBRE Research Scholar, University of Southern Mississippi, Jackson, Mississippi, USA
| | - Wei Li
- Department of Physics, Emory University, Atlanta, Georgia, USA
| | - Kristin Edwards
- Department of Cell and Molecular Biology, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Kurt Warncke
- Department of Physics, Emory University, Atlanta, Georgia, USA
| | - Jorge E. Vidal
- Department of Cell and Molecular Biology, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Center for Immunology and Microbial Research, School of Medicine, University of Mississippi Medical Center, Jackson, Mississippi, USA
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Alibayov B, Scasny A, Vidal AGJ, Murin L, Wong S, Edwards KS, Eichembaun Z, Punshon T, Jackson BP, Hopp MT, McDaniel LS, Akerley BJ, Imhof D, Vidal JE. Oxidation of hemoglobin in the lung parenchyma facilitates the differentiation of pneumococci into encapsulated bacteria. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.14.567109. [PMID: 38014009 PMCID: PMC10680745 DOI: 10.1101/2023.11.14.567109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Pneumococcal pneumonia causes cytotoxicity in the lung parenchyma but the underlying mechanism involves multiple factors contributing to cell death. Here, we discovered that hydrogen peroxide produced by Streptococcus pneumoniae (Spn-H 2 O 2 ) plays a pivotal role by oxidizing hemoglobin, leading to its polymerization and subsequent release of labile heme. At physiologically relevant levels, heme selected a population of encapsulated pneumococci. In the absence of capsule and Spn-H 2 O 2 , host intracellular heme exhibited toxicity towards pneumococci, thus acting as an antibacterial mechanism. Further investigation revealed that heme-mediated toxicity required the ABC transporter GlnPQ. In vivo experiments demonstrated that pneumococci release H 2 O 2 to cause cytotoxicity in bronchi and alveoli through the non-proteolytic degradation of intracellular proteins such as actin, tubulin and GAPDH. Overall, our findings uncover a mechanism of lung toxicity mediated by oxidative stress that favor the growth of encapsulated pneumococci suggesting a therapeutic potential by targeting oxidative reactions. Graphical abstract Highlights Oxidation of hemoglobin by Streptococcus pneumoniae facilitates differentiation to encapsulated pneumococci in vivo Differentiated S. pneumoniae produces capsule and hydrogen peroxide (Spn-H 2 O 2 ) as defense mechanism against host heme-mediated toxicity. Spn-H 2 O 2 -induced lung toxicity causes the oxidation and non-proteolytic degradation of intracellular proteins tubulin, actin, and GAPDH. The ABC transporter GlnPQ is a heme-binding complex that makes Spn susceptible to heme toxicity.
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Scasny A, Alibayov B, Khan F, Rao SJ, Murin L, Jop Vidal AG, Smith P, Wei L, Edwards K, Warncke K, Vidal JE. Oxidation of hemoproteins by Streptococcus pneumoniae collapses the cell cytoskeleton and disrupts mitochondrial respiration leading to cytotoxicity of human lung cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.07.544089. [PMID: 37333138 PMCID: PMC10274756 DOI: 10.1101/2023.06.07.544089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Streptococcus pneumoniae (Spn) causes pneumonia that kills millions through acute toxicity and invasion of the lung parenchyma. During aerobic respiration, Spn releases hydrogen peroxide (Spn-H 2 O 2 ), as a by-product of enzymes SpxB and LctO, and causes cell death with signs of both apoptosis and pyroptosis by oxidizing unknown cell targets. Hemoproteins are molecules essential for life and prone to oxidation by H 2 O 2 . We recently demonstrated that during infection-mimicking conditions, Spn-H 2 O 2 oxidizes the hemoprotein hemoglobin (Hb), releasing toxic heme. In this study, we investigated details of the molecular mechanism(s) by which the oxidation of hemoproteins by Spn-H 2 O 2 causes human lung cell death. Spn strains, but not H 2 O 2 -deficient SpnΔ spxB Δ lctO strains caused time-dependent cell cytotoxicity characterized by the rearrangement of the actin, the loss of the microtubule cytoskeleton and nuclear contraction. Disruption of the cell cytoskeleton correlated with the presence of invasive pneumococci and an increase of intracellular reactive oxygen species. In cell culture, the oxidation of Hb or cytochrome c (Cyt c ) caused DNA degradation and mitochondrial dysfunction from inhibition of complex I-driven respiration, which was cytotoxic to human alveolar cells. Oxidation of hemoproteins resulted in the creation of a radical, which was identified as a protein derived side chain tyrosyl radical by using electron paramagnetic resonance (EPR). Thus, we demonstrate that Spn invades lung cells, releasing H 2 O 2 that oxidizes hemoproteins, including Cyt c , catalyzing the formation of a tyrosyl side chain radical on Hb and causing mitochondrial disruption, that ultimately leads to the collapse of the cell cytoskeleton.
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Kruckow KL, Zhao K, Bowdish DME, Orihuela CJ. Acute organ injury and long-term sequelae of severe pneumococcal infections. Pneumonia (Nathan) 2023; 15:5. [PMID: 36870980 PMCID: PMC9985869 DOI: 10.1186/s41479-023-00110-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Accepted: 01/31/2023] [Indexed: 03/06/2023] Open
Abstract
Streptococcus pneumoniae (Spn) is a major public health problem, as it is a main cause of otitis media, community-acquired pneumonia, bacteremia, sepsis, and meningitis. Acute episodes of pneumococcal disease have been demonstrated to cause organ damage with lingering negative consequences. Cytotoxic products released by the bacterium, biomechanical and physiological stress resulting from infection, and the corresponding inflammatory response together contribute to organ damage accrued during infection. The collective result of this damage can be acutely life-threatening, but among survivors, it also contributes to the long-lasting sequelae of pneumococcal disease. These include the development of new morbidities or exacerbation of pre-existing conditions such as COPD, heart disease, and neurological impairments. Currently, pneumonia is ranked as the 9th leading cause of death, but this estimate only considers short-term mortality and likely underestimates the true long-term impact of disease. Herein, we review the data that indicates damage incurred during acute pneumococcal infection can result in long-term sequelae which reduces quality of life and life expectancy among pneumococcal disease survivors.
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Affiliation(s)
- Katherine L Kruckow
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Kevin Zhao
- McMaster Immunology Research Centre and the Firestone Institute for Respiratory Health, McMaster University, Hamilton, Canada
| | - Dawn M E Bowdish
- McMaster Immunology Research Centre and the Firestone Institute for Respiratory Health, McMaster University, Hamilton, Canada
| | - Carlos J Orihuela
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, USA.
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Lim DJ, Skinner D, West JM, Ayinala S, Zhang S, Grayson JW, Woodworth BA, Cho DY. In vitro evaluation of a novel oxygen-generating biomaterial for chronic rhinosinusitis therapy. Int Forum Allergy Rhinol 2022; 12:181-190. [PMID: 34448372 PMCID: PMC8792167 DOI: 10.1002/alr.22875] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/29/2021] [Accepted: 07/12/2021] [Indexed: 02/03/2023]
Abstract
BACKGROUND Hypoxia due to closure at the ostiomeatal complex is widely considered one of the major pathogenic mechanisms leading to chronic inflammation in chronic rhinosinusitis (CRS). The objective of this study was to develop and characterize an oxygen-generating biomaterial (OGB) as an innovative treatment strategy for CRS. METHODS An OGB was fabricated by coating hydrophobic beeswax (BW, 15mg or 30mg) on the surface of calcium peroxide - catalase complex (CPO-CA, 30mg) and characterized using scanning electron microscopy (SEM). In vitro releases of both oxygen and hydrogen peroxide (H2 O2 ) were spectrophotometrically quantified, and cytotoxicity in human sinonasal epithelial cells (HSNECs) was evaluated. The influence of OGB on transepithelial Cl- secretion was also determined by pharmacologically manipulating HSNECs, cultured under hypoxic conditions, in Ussing chambers. RESULTS Three groups of OGBs: (1) CPO only; (2) CPO coated with CA and BW (1:1 ratio, CPO-CA(1)-BW(1)); and (3) CPO coated with CA and BW (1:0.5 ratio, CPO-CA(1)-BW(0.5) were analyzed for accumulated oxygen release over 7 days: highest release (mmol/mg) was observed in CPO-CA(1)-BW(1) = 0.11 ± 0.003, followed by CPO-CA(1)-BW(0.5) = 0.08 ± 0.010, and CPO = 0.05 ± 0.004 (p < 0.0001). H2 O2 production (mM) was significantly higher in CPO (1.87 ± 0.50) compared to CPO-CA (1)-BW(1) (0.00 ± 0.00) (p < 0.001) after 24 h. CPO-CA(1)-BW(1) showed significantly reduced cytotoxicity and increased Cl- transport compared to the CPO group. CONCLUSION A novel OGB (CPO-CA-BW complex) exhibited sustained oxygen release over 7 days without significant cytotoxicity after 24 h in vitro. Preclinical studies evaluating the efficacy of OGB in CRS are warranted, especially for potential therapy in an obstruction-based CRS model.
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Affiliation(s)
- Dong-Jin Lim
- Department of Otolaryngology Head & Neck Surgery, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Daniel Skinner
- Department of Otolaryngology Head & Neck Surgery, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - John M. West
- Department of Otolaryngology Head & Neck Surgery, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Samrath Ayinala
- Department of Otolaryngology Head & Neck Surgery, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Shaoyan Zhang
- Department of Otolaryngology Head & Neck Surgery, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Jessica W. Grayson
- Department of Otolaryngology Head & Neck Surgery, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Bradford A. Woodworth
- Department of Otolaryngology Head & Neck Surgery, University of Alabama at Birmingham, Birmingham, Alabama, United States of America,,Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Do-Yeon Cho
- Department of Otolaryngology Head & Neck Surgery, University of Alabama at Birmingham, Birmingham, Alabama, United States of America,,Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, United States of America,Division of Otolaryngology, Department of Surgery, Veterans Affairs, Birmingham Alabama, United States of America
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Bricmont N, Alexandru M, Louis B, Papon JF, Kempeneers C. Ciliary Videomicroscopy: A Long Beat from the European Respiratory Society Guidelines to the Recognition as a Confirmatory Test for Primary Ciliary Dyskinesia. Diagnostics (Basel) 2021; 11:diagnostics11091700. [PMID: 34574040 PMCID: PMC8471803 DOI: 10.3390/diagnostics11091700] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/08/2021] [Accepted: 09/08/2021] [Indexed: 11/16/2022] Open
Abstract
Primary ciliary dyskinesia (PCD) is a rare inherited ciliopathy in which respiratory cilia are stationary or dyskinetic. The clinical presentation of PCD is highly non-specific since it includes infections and disorders of the upper (otitis and rhinosinusitis) and lower (neonatal respiratory distress, bronchitis, pneumonia and bronchiectasis) airways, starting in early life. Clinical examination alone does not allow a PCD diagnosis, which relies on several concordant tests, since none are sensitive or specific enough alone. Despite being the most sensitive and specific test to diagnose PCD, digital high-speed videomicroscopy (DHSV) is not sufficiently standardized, preventing its use with complete confidence as a confirmatory diagnostic test for PCD, or its inclusion in a diagnostic algorithm. Since the 2017 ERS recommendations for PCD diagnosis, three main issues remain to be solved in order to optimize DHSV ciliary beating evaluation: the problem in defining an accurate sensitivity and specificity as there is no gold standard method to diagnose all PCD cases, a lack of standardization in the operating procedure for processing respiratory samples, and in the choice of measured parameters (self-operating or not). The development of new automated analysis approaches is promising and will require full clinical validation.
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Affiliation(s)
- Noemie Bricmont
- Pneumology Laboratory, I3 Group, GIGA Research Center, University of Liège, 4000 Liège, Belgium;
- Correspondence:
| | - Mihaela Alexandru
- ENT Department, Assistance Publique-Hôpitaux de Paris (AP-HP), Université Paris-Saclay, Hôpital Bicêtre, 94270 Le Kremlin-Bicêtre, France; (M.A.); (J.-F.P.)
| | - Bruno Louis
- Institut Mondor de Recherche Biomédicale INSERM-UPEC UMR 955, CNRS ERL7000, 94010 Créteil, France;
| | - Jean-François Papon
- ENT Department, Assistance Publique-Hôpitaux de Paris (AP-HP), Université Paris-Saclay, Hôpital Bicêtre, 94270 Le Kremlin-Bicêtre, France; (M.A.); (J.-F.P.)
- Institut Mondor de Recherche Biomédicale INSERM-UPEC UMR 955, CNRS ERL7000, 94010 Créteil, France;
| | - Céline Kempeneers
- Pneumology Laboratory, I3 Group, GIGA Research Center, University of Liège, 4000 Liège, Belgium;
- Division of Respirology, Department of Pediatrics, University Hospital Liège, 4000 Liège, Belgium
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Surabhi S, Jachmann LH, Shumba P, Burchhardt G, Hammerschmidt S, Siemens N. Hydrogen Peroxide Is Crucial for NLRP3 Inflammasome-Mediated IL-1β Production and Cell Death in Pneumococcal Infections of Bronchial Epithelial Cells. J Innate Immun 2021; 14:192-206. [PMID: 34515145 PMCID: PMC9149442 DOI: 10.1159/000517855] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 06/14/2021] [Indexed: 11/19/2022] Open
Abstract
Epithelial cells play a crucial role in detection of the pathogens as well as in initiation of the host immune response. Streptococcus pneumoniae (pneumococcus) is a typical colonizer of the human nasopharynx, which can disseminate to the lower respiratory tract and subsequently cause severe invasive diseases such as pneumonia, sepsis, and meningitis. Hydrogen peroxide (H2O2) is produced by pneumococci as a product of the pyruvate oxidase SpxB. However, its role as a virulence determinant in pneumococcal infections of the lower respiratory tract is not well understood. In this study, we investigated the role of pneumococcal-derived H2O2 in initiating epithelial cell death by analyzing the interplay between 2 key cell death pathways, namely, apoptosis and pyroptosis. We demonstrate that H2O2 primes as well as activates the NLRP3 inflammasome and thereby mediates IL-1β production and release. Furthermore, we show that pneumococcal H2O2 causes cell death via the activation of both apoptotic as well as pyroptotic pathways which are mediated by the activation of caspase-3/7 and caspase-1, respectively. However, H2O2-mediated IL-1β release itself occurs mainly via apoptosis.
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Affiliation(s)
- Surabhi Surabhi
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Lana H Jachmann
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Patience Shumba
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Gerhard Burchhardt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Sven Hammerschmidt
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
| | - Nikolai Siemens
- Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, Greifswald, Germany
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Morimura A, Hamaguchi S, Akeda Y, Tomono K. Mechanisms Underlying Pneumococcal Transmission and Factors Influencing Host-Pneumococcus Interaction: A Review. Front Cell Infect Microbiol 2021; 11:639450. [PMID: 33996623 PMCID: PMC8113816 DOI: 10.3389/fcimb.2021.639450] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 04/06/2021] [Indexed: 01/21/2023] Open
Abstract
Streptococcus pneumoniae (also called pneumococcus) is not only a commensal that frequently colonizes the human upper respiratory tract but also a pathogen that causes pneumonia, sepsis, and meningitis. The mechanism of pneumococcal infection has been extensively studied, but the process of transmission has not been fully elucidated because of the lack of tractable animal models. Novel animal models of transmission have enabled further progress in investigating pneumococcal transmission mechanisms including the processes such as pneumococcal shedding, survival in the external environment, and adherence to the nasopharynx of a new host. Herein, we present a review on these animal models, recent research findings about pneumococcal transmission, and factors influencing the host-pneumococcus interaction.
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Affiliation(s)
- Ayumi Morimura
- Department of Infection Control and Prevention, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Shigeto Hamaguchi
- Department of Infection Control and Prevention, Osaka University Graduate School of Medicine, Osaka, Japan.,Division of Infection Control and Prevention, Osaka University Hospital, Osaka, Japan
| | - Yukihiro Akeda
- Department of Infection Control and Prevention, Osaka University Graduate School of Medicine, Osaka, Japan.,Division of Infection Control and Prevention, Osaka University Hospital, Osaka, Japan.,Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Kazunori Tomono
- Department of Infection Control and Prevention, Osaka University Graduate School of Medicine, Osaka, Japan.,Division of Infection Control and Prevention, Osaka University Hospital, Osaka, Japan
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9
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Orlandi RR, Kingdom TT, Smith TL, Bleier B, DeConde A, Luong AU, Poetker DM, Soler Z, Welch KC, Wise SK, Adappa N, Alt JA, Anselmo-Lima WT, Bachert C, Baroody FM, Batra PS, Bernal-Sprekelsen M, Beswick D, Bhattacharyya N, Chandra RK, Chang EH, Chiu A, Chowdhury N, Citardi MJ, Cohen NA, Conley DB, DelGaudio J, Desrosiers M, Douglas R, Eloy JA, Fokkens WJ, Gray ST, Gudis DA, Hamilos DL, Han JK, Harvey R, Hellings P, Holbrook EH, Hopkins C, Hwang P, Javer AR, Jiang RS, Kennedy D, Kern R, Laidlaw T, Lal D, Lane A, Lee HM, Lee JT, Levy JM, Lin SY, Lund V, McMains KC, Metson R, Mullol J, Naclerio R, Oakley G, Otori N, Palmer JN, Parikh SR, Passali D, Patel Z, Peters A, Philpott C, Psaltis AJ, Ramakrishnan VR, Ramanathan M, Roh HJ, Rudmik L, Sacks R, Schlosser RJ, Sedaghat AR, Senior BA, Sindwani R, Smith K, Snidvongs K, Stewart M, Suh JD, Tan BK, Turner JH, van Drunen CM, Voegels R, Wang DY, Woodworth BA, Wormald PJ, Wright ED, Yan C, Zhang L, Zhou B. International consensus statement on allergy and rhinology: rhinosinusitis 2021. Int Forum Allergy Rhinol 2021; 11:213-739. [PMID: 33236525 DOI: 10.1002/alr.22741] [Citation(s) in RCA: 385] [Impact Index Per Article: 128.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 11/09/2020] [Indexed: 02/06/2023]
Abstract
I. EXECUTIVE SUMMARY BACKGROUND: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR-RS-2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence-based findings of the document. METHODS ICAR-RS presents over 180 topics in the forms of evidence-based reviews with recommendations (EBRRs), evidence-based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. RESULTS ICAR-RS-2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence-based management algorithm is provided. CONCLUSION This ICAR-RS-2021 executive summary provides a compilation of the evidence-based recommendations for medical and surgical treatment of the most common forms of RS.
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Affiliation(s)
| | | | | | | | | | - Amber U Luong
- University of Texas Medical School at Houston, Houston, TX
| | | | - Zachary Soler
- Medical University of South Carolina, Charleston, SC
| | - Kevin C Welch
- Feinberg School of Medicine, Northwestern University, Chicago, IL
| | | | | | | | | | - Claus Bachert
- Ghent University, Ghent, Belgium.,Karolinska Institute, Stockholm, Sweden.,Sun Yatsen University, Gangzhou, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - David A Gudis
- Columbia University Irving Medical Center, New York, NY
| | - Daniel L Hamilos
- Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | | | - Richard Harvey
- University of New South Wales and Macquarie University, Sydney, New South Wales, Australia
| | | | | | | | | | - Amin R Javer
- University of British Columbia, Vancouver, British Columbia, Canada
| | | | | | | | | | | | | | | | | | | | | | - Valerie Lund
- Royal National Throat Nose and Ear Hospital, UCLH, London, UK
| | - Kevin C McMains
- Uniformed Services University of Health Sciences, San Antonio, TX
| | | | - Joaquim Mullol
- IDIBAPS Hospital Clinic, University of Barcelona, Barcelona, Spain
| | | | | | | | | | | | | | | | | | | | - Alkis J Psaltis
- University of Adelaide, Adelaide, South Australia, Australia
| | | | | | | | - Luke Rudmik
- University of Calgary, Calgary, Alberta, Canada
| | - Raymond Sacks
- University of New South Wales, Sydney, New South Wales, Australia
| | | | | | | | | | | | | | | | | | | | | | | | | | - De Yun Wang
- National University of Singapore, Singapore, Singapore
| | | | | | | | - Carol Yan
- University of California San Diego, La Jolla, CA
| | - Luo Zhang
- Capital Medical University, Beijing, China
| | - Bing Zhou
- Capital Medical University, Beijing, China
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10
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Kuek LE, Lee RJ. First contact: the role of respiratory cilia in host-pathogen interactions in the airways. Am J Physiol Lung Cell Mol Physiol 2020; 319:L603-L619. [PMID: 32783615 PMCID: PMC7516383 DOI: 10.1152/ajplung.00283.2020] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/28/2020] [Accepted: 07/28/2020] [Indexed: 02/07/2023] Open
Abstract
Respiratory cilia are the driving force of the mucociliary escalator, working in conjunction with secreted airway mucus to clear inhaled debris and pathogens from the conducting airways. Respiratory cilia are also one of the first contact points between host and inhaled pathogens. Impaired ciliary function is a common pathological feature in patients with chronic airway diseases, increasing susceptibility to respiratory infections. Common respiratory pathogens, including viruses, bacteria, and fungi, have been shown to target cilia and/or ciliated airway epithelial cells, resulting in a disruption of mucociliary clearance that may facilitate host infection. Despite being an integral component of airway innate immunity, the role of respiratory cilia and their clinical significance during airway infections are still poorly understood. This review examines the expression, structure, and function of respiratory cilia during pathogenic infection of the airways. This review also discusses specific known points of interaction of bacteria, fungi, and viruses with respiratory cilia function. The emerging biological functions of motile cilia relating to intracellular signaling and their potential immunoregulatory roles during infection will also be discussed.
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Affiliation(s)
- Li Eon Kuek
- Department of Otorhinolaryngology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Robert J Lee
- Department of Otorhinolaryngology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
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11
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Joskova M, Mokry J, Franova S. Respiratory Cilia as a Therapeutic Target of Phosphodiesterase Inhibitors. Front Pharmacol 2020; 11:609. [PMID: 32435198 PMCID: PMC7218135 DOI: 10.3389/fphar.2020.00609] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 04/20/2020] [Indexed: 11/30/2022] Open
Abstract
Mucociliary clearance is an essential airway defense mechanism dependent predominantly on the proper ciliary function and mucus rheology. The crucial role of cilia is evident in `a variety of respiratory diseases, as the ciliary dysfunction is associated with a progressive decline in lung function over time. The activity of cilia is under supervision of multiple physiological regulators, including second messengers. Their role is to enable a movement in coordinated metachronal waves at certain beat frequency. Ciliary function can be modulated by various stimuli, including agents from the group of beta2 agonists, cholinergic drugs, and adenosine triphosphate (ATP). They trigger cilia to move faster in response to elevated cytoplasmic Ca2+ originated from intracellular sources or replenished from extracellular space. Well-known cilia-stimulatory effect of Ca2+ ions can be abolished or even reversed by modulating the phosphodiesterase (PDE)-mediated breakdown of cyclic adenosine monophosphate (cAMP) since the overall change in ciliary beating has been dependent on the balance between Ca2+ ions and cAMP. Moreover, in chronic respiratory diseases, high ATP levels may contribute to cAMP hydrolysis and thus to a decrease in the ciliary beat frequency (CBF). The role of PDE inhibitors in airway cilia-driven transport may help in prevention of progressive loss of pulmonary function often observed despite current therapy. Furthermore, administration of selective PDE inhibitors by inhalation lowers the risk of their systemic effects. Based on this review we may conclude that selective (PDE1, PDE4) or dual PDE inhibitors (PDE3/4) increase the intracellular level of cyclic nucleotides in airway epithelial cells and thus may be an important target in the development of new inhaled mucokinetic agents. Further research is required to provide evidence of their effectiveness and feasibility regarding their cilia-modulating properties.
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Affiliation(s)
- Marta Joskova
- Department of Pharmacology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia
| | - Juraj Mokry
- Department of Pharmacology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia
| | - Sona Franova
- Department of Pharmacology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, Martin, Slovakia
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12
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Price ME, Gerald CL, Pavlik JA, Schlichte SL, Zimmerman MC, DeVasure JM, Wyatt TA, Sisson JH. Loss of cAMP-dependent stimulation of isolated cilia motility by alcohol exposure is oxidant-dependent. Alcohol 2019; 80:91-98. [PMID: 30291947 DOI: 10.1016/j.alcohol.2018.09.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 09/18/2018] [Accepted: 09/26/2018] [Indexed: 02/07/2023]
Abstract
Alcohol exposure is associated with decreased mucociliary clearance, a key innate defense essential to lung immunity. Previously, we identified that prolonged alcohol exposure results in dysfunction of airway cilia that persists at the organelle level. This dysfunction is characterized by a loss of 3',5'-cyclic adenosine monophosphate (cAMP)-mediated cilia stimulation. However, whether or not ciliary dysfunction develops intrinsically at the organelle level has not been explored. We hypothesized that prolonged alcohol exposure directly to isolated demembranated cilia (axonemes) causes ciliary dysfunction. To test this hypothesis, we exposed isolated axonemes to alcohol (100 mM) for 1-24 h and assessed ciliary beat frequency (CBF) in response to cAMP at 1, 3, 4, 6, and 24 h post-exposure. We found that after 1 h of alcohol exposure, cilia axonemes do not increase CBF in response to cAMP. Importantly, by 6 h after the initial exposure to alcohol, cAMP-mediated CBF was restored to control levels. Additionally, we found that thioredoxin reverses ciliary dysfunction in axonemes exposed to alcohol. Finally, we identified, using a combination of a xanthine oxidase oxidant-generating system, direct application of hydrogen peroxide, and electron paramagnetic resonance, that hydrogen peroxide versus superoxide, is likely the key oxidant species driving alcohol-induced ciliary dysfunction in isolated axonemes. These data highlight the role of alcohol to stimulate local production of oxidants in the axoneme to cause ciliary dysfunction. Additionally, these data specifically add hydrogen peroxide as a potential therapeutic target in the treatment or prevention of alcohol-associated ciliary dysfunction and subsequent pneumonia.
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Affiliation(s)
- Michael E Price
- Pulmonary, Critical Care, Sleep, and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, United States; Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Carresse L Gerald
- Department of Environmental, Earth and Geospatial Science, North Carolina Central University, Durham, NC, United States
| | - Jacqueline A Pavlik
- Pulmonary, Critical Care, Sleep, and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, United States
| | - Sarah L Schlichte
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Matthew C Zimmerman
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Jane M DeVasure
- Pulmonary, Critical Care, Sleep, and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, United States
| | - Todd A Wyatt
- Pulmonary, Critical Care, Sleep, and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, United States; Department of Environmental, Agricultural, and Occupational Health, University of Nebraska Medical Center, Omaha, NE, United States; Department of Veterans Affairs Nebraska-Western Iowa Health Care System, Research Service, Omaha, NE, United States
| | - Joseph H Sisson
- Pulmonary, Critical Care, Sleep, and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, United States.
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13
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van den Broek MFL, De Boeck I, Kiekens F, Boudewyns A, Vanderveken OM, Lebeer S. Translating Recent Microbiome Insights in Otitis Media into Probiotic Strategies. Clin Microbiol Rev 2019; 32:e00010-18. [PMID: 31270125 PMCID: PMC6750133 DOI: 10.1128/cmr.00010-18] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The microbiota of the upper respiratory tract (URT) protects the host from bacterial pathogenic colonization by competing for adherence to epithelial cells and by immune response regulation that includes the activation of antimicrobial and (anti-)inflammatory components. However, environmental or host factors can modify the microbiota to an unstable community that predisposes the host to infection or inflammation. One of the URT diseases most often encountered in children is otitis media (OM). The role of pathogenic bacteria like Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis in the pathogenesis of OM is well documented. Results from next-generation-sequencing (NGS) studies reveal other bacterial taxa involved in OM, such as Turicella and Alloiococcus Such studies can also identify bacterial taxa that are potentially protective against URT infections, whose beneficial action needs to be substantiated in relevant experimental models and clinical trials. Of note, lactic acid bacteria (LAB) are members of the URT microbiota and associated with a URT ecosystem that is deemed healthy, based on NGS and some experimental and clinical studies. These observations have formed the basis of this review, in which we describe the current knowledge of the molecular and clinical potential of LAB in the URT, which is currently underexplored in microbiome and probiotic research.
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Affiliation(s)
- Marianne F L van den Broek
- Environmental Ecology and Applied Microbiology Research Group, Department of Bioscience Engineering, University of Antwerp, Antwerp, Belgium
| | - Ilke De Boeck
- Environmental Ecology and Applied Microbiology Research Group, Department of Bioscience Engineering, University of Antwerp, Antwerp, Belgium
| | - Filip Kiekens
- Laboratory of Pharmaceutical Technology and Biopharmacy, Department of Pharmaceutical, Biomedical and Veterinary Sciences, University of Antwerp, Wilrijk, Belgium
| | - An Boudewyns
- Department of Otorhinolaryngology, Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
| | - Olivier M Vanderveken
- Department of Otorhinolaryngology, Head and Neck Surgery, Antwerp University Hospital, Edegem, Belgium
- Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Sarah Lebeer
- Environmental Ecology and Applied Microbiology Research Group, Department of Bioscience Engineering, University of Antwerp, Antwerp, Belgium
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14
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Abstract
Streptococcus pneumoniae (the pneumoccus) is the leading cause of otitis media, community-acquired pneumonia, and bacterial meningitis. The success of the pneumococcus stems from its ability to persist in the population as a commensal and avoid killing by immune system. This chapter first reviews the molecular mechanisms that allow the pneumococcus to colonize and spread from one anatomical site to the next. Then, it discusses the mechanisms of inflammation and cytotoxicity during emerging and classical pneumococcal infections.
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15
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Price ME, Sisson JH. Redox regulation of motile cilia in airway disease. Redox Biol 2019; 27:101146. [PMID: 30833143 PMCID: PMC6859573 DOI: 10.1016/j.redox.2019.101146] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 02/14/2019] [Accepted: 02/15/2019] [Indexed: 02/07/2023] Open
Abstract
Motile cilia on airway cells are necessary for clearance of mucus-trapped particles out of the lung. Ciliated airway epithelial cells are uniquely exposed to oxidants through trapping of particles, debris and pathogens in mucus and the direct exposure to inhaled oxidant gases. Dynein ATPases, the motors driving ciliary motility, are sensitive to the local redox environment within each cilium. Several redox-sensitive cilia-localized proteins modulate dynein activity and include Protein Kinase A, Protein Kinase C, and Protein Phosphatase 1. Moreover, cilia are rich in known redox regulatory proteins and thioredoxin domain-containing proteins that are critical in maintaining a balanced redox environment. Importantly, a nonsense mutation in TXNDC3, which contains a thioredoxin motif, has recently been identified as disease-causing in Primary Ciliary Dyskinesia, a hereditary motile cilia disease resulting in impaired mucociliary clearance. Here we review current understanding of the role(s) oxidant species play in modifying airway ciliary function. We focus on oxidants generated in the airways, cilia redox targets that modulate ciliary beating and imbalances in redox state that impact health and disease. Finally, we review disease models such as smoking, asthma, alcohol drinking, and infections as well as the direct application of oxidants that implicate redox balance as a modulator of cilia motility.
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Affiliation(s)
- Michael E Price
- University of Nebraska Medical Center, Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, Omaha, NE, USA; University of Nebraska Medical Center, Department of Cellular & Integrative Physiology, Omaha, NE, USA.
| | - Joseph H Sisson
- University of Nebraska Medical Center, Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, Omaha, NE, USA.
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16
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Bailey KL, Kharbanda KK, Katafiasz DM, Sisson JH, Wyatt TA. Oxidative stress associated with aging activates protein kinase Cε, leading to cilia slowing. Am J Physiol Lung Cell Mol Physiol 2018; 315:L882-L890. [PMID: 30211654 PMCID: PMC6295504 DOI: 10.1152/ajplung.00033.2018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 08/24/2018] [Accepted: 08/27/2018] [Indexed: 11/22/2022] Open
Abstract
Older people are four times more likely to develop pneumonia than younger people. As we age, many components of pulmonary innate immunity are impaired, including slowing of mucociliary clearance. Ciliary beat frequency (CBF) is a major determinant of mucociliary clearance, and it slows as we age. We hypothesized that CBF is slowed in aging because of increased oxidative stress, which activates PKCε signaling. We pharmacologically inhibited PKCε in ex vivo mouse models of aging. We measured a slowing of CBF with aging that was reversed with inhibition using the novel PKC inhibitor, Ro-31-8220, as well as the PKCε inhibitor, PKCe141. Inhibition of PKCε using siRNA in mouse trachea also returned CBF to normal. In addition, antioxidants decrease PKCε activity and speed cilia. We also aged wild-type and PKCε KO mice and measured CBF. The PKCε KO mice were spared from the CBF slowing of aging. Using human airway epithelial cells from younger and older donors at air-liquid interface (ALI), we inhibited PKCε with siRNA. We measured a slowing of CBF with aging that was reversed with siRNA inhibition of PKCε. In addition, we measured bead clearance speeds in human ALI, which demonstrated a decrease in bead velocity with aging and a return to baseline after inhibition of PKCε. In summary, in human and mouse models, aging is associated with increased oxidant stress, which activates PKCε and slows CBF.
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Affiliation(s)
- Kristina L Bailey
- Pulmonary, Critical Care, Sleep and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center , Omaha, Nebraska
- Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, Nebraska
| | - Kusum K Kharbanda
- Pulmonary, Critical Care, Sleep and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center , Omaha, Nebraska
- Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, Nebraska
- Departments of Internal Medicine and Biochemistry and Molecular Biology, University of Nebraska Medical Center , Omaha, Nebraska
| | - Dawn M Katafiasz
- Pulmonary, Critical Care, Sleep and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center , Omaha, Nebraska
| | - Joseph H Sisson
- Pulmonary, Critical Care, Sleep and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center , Omaha, Nebraska
| | - Todd A Wyatt
- Pulmonary, Critical Care, Sleep and Allergy Division, Department of Internal Medicine, University of Nebraska Medical Center , Omaha, Nebraska
- Department of Environmental, Agricultural, and Occupational Health, University of Nebraska Medical Center , Omaha, Nebraska
- Veterans Affairs Nebraska-Western Iowa Health Care System, Omaha, Nebraska
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17
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Li X, Yu Y, Gorshkov B, Haigh S, Bordan Z, Weintraub D, Rudic RD, Chakraborty T, Barman SA, Verin AD, Su Y, Lucas R, Stepp DW, Chen F, Fulton DJR. Hsp70 Suppresses Mitochondrial Reactive Oxygen Species and Preserves Pulmonary Microvascular Barrier Integrity Following Exposure to Bacterial Toxins. Front Immunol 2018; 9:1309. [PMID: 29951058 PMCID: PMC6008539 DOI: 10.3389/fimmu.2018.01309] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 05/25/2018] [Indexed: 01/22/2023] Open
Abstract
Pneumonia is a leading cause of death in children and the elderly worldwide, accounting for 15% of all deaths of children under 5 years old. Streptococcus pneumoniae is a common and aggressive cause of pneumonia and can also contribute to meningitis and sepsis. Despite the widespread use of antibiotics, mortality rates for pneumonia remain unacceptably high in part due to the release of bacterial toxins. Pneumolysin (PLY) is a cholesterol-dependent toxin that is produced by Streptococcus, and it is both necessary and sufficient for the development of the extensive pulmonary permeability edema that underlies acute lung injury. The mechanisms by which PLY disrupts the pulmonary endothelial barrier are not fully understood. Previously, we found that reactive oxygen species (ROS) contribute to the barrier destructive effects of PLY and identified an unexpected but potent role of Hsp70 in suppressing ROS production. The ability of Hsp70 to influence PLY-induced barrier dysfunction is not yet described, and the goal of the current study was to identify whether Hsp70 upregulation is an effective strategy to protect the lung microvascular endothelial barrier from G+ bacterial toxins. Overexpression of Hsp70 via adenovirus-mediated gene transfer attenuated PLY-induced increases in permeability in human lung microvascular endothelial cells (HLMVEC) with no evidence of cytotoxicity. To adopt a more translational approach, we employed a pharmacological approach using geranylgeranylacetone (GGA) to acutely upregulate endogenous Hsp70 expression. Following acute treatment (6 h) with GGA, HLMVECs exposed to PLY displayed improved cell viability and enhanced endothelial barrier function as measured by both Electric Cell-substrate Impedance Sensing (ECIS) and transwell permeability assays compared to control treated cells. PLY promoted increased mitochondrial ROS, decreased mitochondrial oxygen consumption, and increased caspase 3 cleavage and cell death, which were collectively improved in cells pretreated with GGA. In mice, IP pretreatment with GGA 24 h prior to IT administration of PLY resulted in significantly less Evans Blue Dye extravasation compared to vehicle, indicating preserved endothelial barrier integrity and suggesting that the acute upregulation of Hsp70 may be an effective therapeutic approach in the treatment of lung injury associated with pneumonia.
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Affiliation(s)
- Xueyi Li
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Yanfang Yu
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia.,Department of Forensic Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Boris Gorshkov
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Stephen Haigh
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Zsuzsanna Bordan
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Daniel Weintraub
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Radu Daniel Rudic
- Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA, United States
| | - Trinad Chakraborty
- Institute for Medical Microbiology, Justus-Liebig University Giessen, Giessen, Germany
| | - Scott A Barman
- Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA, United States
| | - Alexander D Verin
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia
| | - Yunchao Su
- Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA, United States
| | - Rudolf Lucas
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia.,Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA, United States
| | - David W Stepp
- Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA, United States
| | - Feng Chen
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia.,Department of Forensic Medicine, Nanjing Medical University, Nanjing, Jiangsu, China
| | - David J R Fulton
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, Georgia.,Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA, United States
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18
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Anderson R, Feldman C. Review manuscript: Mechanisms of platelet activation by the pneumococcus and the role of platelets in community-acquired pneumonia. J Infect 2017; 75:473-485. [PMID: 28943342 DOI: 10.1016/j.jinf.2017.09.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/13/2017] [Accepted: 09/15/2017] [Indexed: 12/11/2022]
Abstract
There is increasing recognition of the involvement of platelets in orchestrating inflammatory responses, driving the activation of neutrophils, monocytes and vascular endothelium, which, if poorly controlled, may lead to microvascular dysfunction. Importantly, hyperreactivity of platelets has been implicated in the pathogenesis of myocardial injury and the associated particularly high prevalence of acute cardiovascular events in patients with severe community-acquired pneumonia (CAP), of which Streptococcus pneumoniae (pneumococcus) is the most commonly encountered aetiologic agent. In this context, it is noteworthy that a number of studies have documented various mechanisms by which the pneumococcus may directly promote platelet aggregation and activation. The major contributors to platelet activation include several different types of pneumococcal adhesin, the pore-forming toxin, pneumolysin, and possibly pathogen-derived hydrogen peroxide, which collectively represent a major focus of the current review. This is followed by an overview of the limited experimental studies together with a larger series of clinical studies mainly focused on all-cause CAP, which have provided evidence in support of associations between alterations in circulating platelet counts, most commonly thrombocytopenia, and a poor clinical outcome. The final section of the review covers, albeit briefly, systemic biomarkers of platelet activation which may have prognostic potential.
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Affiliation(s)
- Ronald Anderson
- Department of Immunology and Institute for Cellular and Molecular Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
| | - Charles Feldman
- Division of Pulmonology, Department of Internal Medicine, Charlotte Maxeke Johannesburg Academic Hospital and Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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19
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Sumioka R, Nakata M, Okahashi N, Li Y, Wada S, Yamaguchi M, Sumitomo T, Hayashi M, Kawabata S. Streptococcus sanguinis induces neutrophil cell death by production of hydrogen peroxide. PLoS One 2017; 12:e0172223. [PMID: 28222125 PMCID: PMC5319702 DOI: 10.1371/journal.pone.0172223] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 02/01/2017] [Indexed: 11/18/2022] Open
Abstract
Streptococcus is the dominant bacterial genus in the human oral cavity and a leading cause of infective endocarditis. Streptococcus sanguinis belongs to the mitis group of streptococci and produces hydrogen peroxide (H2O2) by the action of SpxB, a pyruvate oxidase. In this study, we investigated the involvement of SpxB in survival of S. sanguinis in human blood and whether bacterial H2O2 exhibits cytotoxicity against human neutrophils. Results of a bactericidal test with human whole blood revealed that the spxB mutation in S. sanguinis is detrimental to its survival in blood. When S. sanguinis strains were exposed to isolated neutrophils, the bacterial survival rate was significantly decreased by spxB deletion. Furthermore, human neutrophils exposed to the S. sanguinis wild-type strain, in contrast to those exposed to an spxB mutant strain, underwent cell death with chromatin de-condensation and release of web-like extracellular DNA, reflecting induction of neutrophil extracellular traps (NETs). Since reactive oxygen species-mediated NET induction requires citrullination of arginine residues in histone proteins and subsequent chromatin de-condensation, we examined citrullination levels of histone in infected neutrophils. It is important to note that the citrullinated histone H3 was readily detected in neutrophils infected with the wild-type strain, as compared to infection with the spxB mutant strain. Moreover, decomposition of streptococcal H2O2 with catalase reduced NET induction. These results suggest that H2O2 produced by S. sanguinis provokes cell death of neutrophils and NET formation, thus potentially affecting bacterial survival in the bloodstream.
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Affiliation(s)
- Ryuichi Sumioka
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan
- Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan
| | - Masanobu Nakata
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan
- * E-mail:
| | - Nobuo Okahashi
- Center for Frontier Oral Science, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan
| | - Yixuan Li
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan
| | - Satoshi Wada
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan
| | - Masaya Yamaguchi
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan
| | - Tomoko Sumitomo
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan
| | - Mikako Hayashi
- Department of Restorative Dentistry and Endodontology, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan
| | - Shigetada Kawabata
- Department of Oral and Molecular Microbiology, Osaka University Graduate School of Dentistry, Suita-Osaka, Japan
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20
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Workman AD, Palmer JN, Adappa ND, Cohen NA. The Role of Bitter and Sweet Taste Receptors in Upper Airway Immunity. Curr Allergy Asthma Rep 2016; 15:72. [PMID: 26492878 DOI: 10.1007/s11882-015-0571-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Over the past several years, taste receptors have emerged as key players in the regulation of innate immune defenses in the mammalian respiratory tract. Several cell types in the airway, including ciliated epithelial cells, solitary chemosensory cells, and bronchial smooth muscle cells, all display chemoresponsive properties that utilize taste receptors. A variety of bitter products secreted by microbes are detected with resultant downstream inflammation, increased mucous clearance, antimicrobial peptide secretion, and direct bacterial killing. Genetic variation of bitter taste receptors also appears to play a role in the susceptibility to infection in respiratory disease states, including that of chronic rhinosinusitis. Ongoing taste receptor research may yield new therapeutics that harness innate immune defenses in the respiratory tract and may offer alternatives to antibiotic treatment. The present review discusses taste receptor-protective responses and analyzes the role these receptors play in mediating airway immune function.
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Affiliation(s)
- Alan D Workman
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Medical Center, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, 19104, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - James N Palmer
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Medical Center, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, 19104, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Nithin D Adappa
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Medical Center, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, 19104, USA.,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Noam A Cohen
- Department of Otorhinolaryngology: Head and Neck Surgery, University of Pennsylvania Medical Center, 5th Floor Ravdin Building, 3400 Spruce Street, Philadelphia, PA, 19104, USA. .,Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA. .,Monell Smell and Taste Center, Philadelphia, PA, USA. .,Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA.
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21
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Orlandi RR, Kingdom TT, Hwang PH, Smith TL, Alt JA, Baroody FM, Batra PS, Bernal-Sprekelsen M, Bhattacharyya N, Chandra RK, Chiu A, Citardi MJ, Cohen NA, DelGaudio J, Desrosiers M, Dhong HJ, Douglas R, Ferguson B, Fokkens WJ, Georgalas C, Goldberg A, Gosepath J, Hamilos DL, Han JK, Harvey R, Hellings P, Hopkins C, Jankowski R, Javer AR, Kern R, Kountakis S, Kowalski ML, Lane A, Lanza DC, Lebowitz R, Lee HM, Lin SY, Lund V, Luong A, Mann W, Marple BF, McMains KC, Metson R, Naclerio R, Nayak JV, Otori N, Palmer JN, Parikh SR, Passali D, Peters A, Piccirillo J, Poetker DM, Psaltis AJ, Ramadan HH, Ramakrishnan VR, Riechelmann H, Roh HJ, Rudmik L, Sacks R, Schlosser RJ, Senior BA, Sindwani R, Stankiewicz JA, Stewart M, Tan BK, Toskala E, Voegels R, Wang DY, Weitzel EK, Wise S, Woodworth BA, Wormald PJ, Wright ED, Zhou B, Kennedy DW. International Consensus Statement on Allergy and Rhinology: Rhinosinusitis. Int Forum Allergy Rhinol 2016; 6 Suppl 1:S22-209. [DOI: 10.1002/alr.21695] [Citation(s) in RCA: 333] [Impact Index Per Article: 41.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 11/13/2015] [Accepted: 11/16/2015] [Indexed: 02/06/2023]
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Valerie Lund
- Royal National Throat Nose and Ear Hospital; London UK
| | - Amber Luong
- University of Texas Medical School at Houston
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22
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Workman AD, Cohen NA. The effect of drugs and other compounds on the ciliary beat frequency of human respiratory epithelium. Am J Rhinol Allergy 2015; 28:454-64. [PMID: 25514481 DOI: 10.2500/ajra.2014.28.4092] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Cilia in the human respiratory tract play a critical role in clearing mucus and debris from the airways. Their function can be affected by a number of drugs or other substances, many of which alter ciliary beat frequency (CBF). This has implications for diseases of the respiratory tract and nasal drug delivery. This article is a systematic review of the literature that examines 229 substances and their effect on CBF. METHODS MEDLINE was the primary database used for data collection. Eligibility criteria based on experimental design were established, and 152 studies were ultimately selected. Each individual trial for the substances tested was noted whenever possible, including concentration, time course, specific effect on CBF, and source of tissue. RESULTS There was a high degree of heterogeneity between the various experiments examined in this article. Substances and their general effects (increase, no effect, decrease) were grouped into six categories: antimicrobials and antivirals, pharmacologics, human biological products, organisms and toxins, drug excipients, and natural compounds/other manipulations. CONCLUSION Organisms, toxins, and drug excipients tend to show a cilioinhibitory effect, whereas substances in all other categories had mixed effects. All studies examined were in vitro experiments, and application of the results in vivo is confounded by several factors. The data presented in this article should be useful in future respiratory research and examination of compounds for therapeutic and drug delivery purposes.
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Affiliation(s)
- Alan D Workman
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Ethanol-induced alcohol dehydrogenase E (AdhE) potentiates pneumolysin in Streptococcus pneumoniae. Infect Immun 2014; 83:108-19. [PMID: 25312953 DOI: 10.1128/iai.02434-14] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Alcohol impairs the host immune system, rendering the host more vulnerable to infection. Therefore, alcoholics are at increased risk of acquiring serious bacterial infections caused by Streptococcus pneumoniae, including pneumonia. Nevertheless, how alcohol affects pneumococcal virulence remains unclear. Here, we showed that the S. pneumoniae type 2 D39 strain is ethanol tolerant and that alcohol upregulates alcohol dehydrogenase E (AdhE) and potentiates pneumolysin (Ply). Hemolytic activity, colonization, and virulence of S. pneumoniae, as well as host cell myeloperoxidase activity, proinflammatory cytokine secretion, and inflammation, were significantly attenuated in adhE mutant bacteria (ΔadhE strain) compared to D39 wild-type bacteria. Therefore, AdhE might act as a pneumococcal virulence factor. Moreover, in the presence of ethanol, S. pneumoniae AdhE produced acetaldehyde and NADH, which subsequently led Rex (redox-sensing transcriptional repressor) to dissociate from the adhE promoter. An increase in AdhE level under the ethanol condition conferred an increase in Ply and H2O2 levels. Consistently, S. pneumoniae D39 caused higher cytotoxicity to RAW 264.7 cells than the ΔadhE strain under the ethanol stress condition, and ethanol-fed mice (alcoholic mice) were more susceptible to infection with the D39 wild-type bacteria than with the ΔadhE strain. Taken together, these data indicate that AdhE increases Ply under the ethanol stress condition, thus potentiating pneumococcal virulence.
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Feldman C, Anderson R. Review: Current and new generation pneumococcal vaccines. J Infect 2014; 69:309-25. [DOI: 10.1016/j.jinf.2014.06.006] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 06/16/2014] [Indexed: 12/22/2022]
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Overview of community-acquired pneumonia and the role of inflammatory mechanisms in the immunopathogenesis of severe pneumococcal disease. Mediators Inflamm 2013; 2013:490346. [PMID: 24453422 PMCID: PMC3886318 DOI: 10.1155/2013/490346] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 11/15/2013] [Accepted: 11/17/2013] [Indexed: 12/23/2022] Open
Abstract
Community-acquired pneumonia (CAP) remains a leading cause of morbidity and mortality among the infectious diseases. Despite the implementation of national pneumococcal polyvalent vaccine-based immunisation strategies targeted at high-risk groups, Streptococcus pneumoniae (the pneumococcus) remains the most common cause of CAP. Notwithstanding the HIV pandemic, major challenges confronting the control of CAP include the range of bacterial and viral pathogens causing this condition, the ever-increasing problem of antibiotic resistance worldwide, and increased vulnerability associated with steadily aging populations in developed countries. These and other risk factors, as well as diagnostic strategies, are covered in the first section of this review. Thereafter, the review is focused on the pneumococcus, specifically the major virulence factors of this microbial pathogen and their role in triggering overexuberant inflammatory responses which contribute to the immunopathogenesis of invasive disease. The final section of the review is devoted to a consideration of pharmacological, anti-inflammatory strategies with adjunctive potential in the antimicrobial chemotherapy of CAP. This is focused on macrolides, corticosteroids, and statins with respect to their modes of anti-inflammatory action, current status, and limitations.
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Mini-review: novel therapeutic strategies to blunt actions of pneumolysin in the lungs. Toxins (Basel) 2013; 5:1244-60. [PMID: 23860351 PMCID: PMC3737495 DOI: 10.3390/toxins5071244] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 06/25/2013] [Accepted: 06/27/2013] [Indexed: 01/11/2023] Open
Abstract
Severe pneumonia is the main single cause of death worldwide in children under five years of age. The main etiological agent of pneumonia is the G+ bacterium Streptococcus pneumoniae, which accounts for up to 45% of all cases. Intriguingly, patients can still die days after commencing antibiotic treatment due to the development of permeability edema, although the pathogen was successfully cleared from their lungs. This condition is characterized by a dramatically impaired alveolar epithelial-capillary barrier function and a dysfunction of the sodium transporters required for edema reabsorption, including the apically expressed epithelial sodium channel (ENaC) and the basolaterally expressed sodium potassium pump (Na+-K+-ATPase). The main agent inducing this edema formation is the virulence factor pneumolysin, a cholesterol-binding pore-forming toxin, released in the alveolar compartment of the lungs when pneumococci are being lysed by antibiotic treatment or upon autolysis. Sub-lytic concentrations of pneumolysin can cause endothelial barrier dysfunction and can impair ENaC-mediated sodium uptake in type II alveolar epithelial cells. These events significantly contribute to the formation of permeability edema, for which currently no standard therapy is available. This review focuses on discussing some recent developments in the search for the novel therapeutic agents able to improve lung function despite the presence of pore-forming toxins. Such treatments could reduce the potentially lethal complications occurring after antibiotic treatment of patients with severe pneumonia.
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Fliegauf M, Sonnen AFP, Kremer B, Henneke P. Mucociliary clearance defects in a murine in vitro model of pneumococcal airway infection. PLoS One 2013; 8:e59925. [PMID: 23527286 PMCID: PMC3602288 DOI: 10.1371/journal.pone.0059925] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 02/19/2013] [Indexed: 12/11/2022] Open
Abstract
Mucociliary airway clearance is an innate defense mechanism that protects the lung from harmful effects of inhaled pathogens. In order to escape mechanical clearance, airway pathogens including Streptococcus pneumoniae (pneumococcus) are thought to inactivate mucociliary clearance by mechanisms such as slowing of ciliary beating and lytic damage of epithelial cells. Pore-forming toxins like pneumolysin, may be instrumental in these processes. In a murine in vitro airway infection model using tracheal epithelial cells grown in air-liquid interface cultures, we investigated the functional consequences on the ciliated respiratory epithelium when the first contact with pneumococci is established. High-speed video microscopy and live-cell imaging showed that the apical infection with both wildtype and pneumolysin-deficient pneumococci caused insufficient fluid flow along the epithelial surface and loss of efficient clearance, whereas ciliary beat frequency remained within the normal range. Three-dimensional confocal microscopy demonstrated that pneumococci caused specific morphologic aberrations of two key elements in the F-actin cytoskeleton: the junctional F-actin at the apical cortex of the lateral cell borders and the apical F-actin, localized within the planes of the apical cell sides at the ciliary bases. The lesions affected the columnar shape of the polarized respiratory epithelial cells. In addition, the planar architecture of the entire ciliated respiratory epithelium was irregularly distorted. Our observations indicate that the mechanical supports essential for both effective cilia strokes and stability of the epithelial barrier were weakened. We provide a new model, where - in pneumococcal infection - persistent ciliary beating generates turbulent fluid flow at non-planar distorted epithelial surface areas, which enables pneumococci to resist mechanical cilia-mediated clearance.
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Affiliation(s)
- Manfred Fliegauf
- Centre of Chronic Immunodeficiency, University Medical Centre Freiburg and University of Freiburg, Freiburg, Germany.
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Abstract
BACKGROUND Cilia are complex and powerful cellular structures of the respiratory mucosa that play a critical role in airway defense. Respiratory epithelium is lined with cilia that perform an integrated and coordinated mechanism called mucociliary clearance. Mucociliary clearance is the process by which cilia transport the mucus blanket overlying respiratory mucosa to the gastrointestinal tract for ingestion. It is the primary means by which the airway clears pathogens, allergens, debris, and toxins. The complex structure and regulatory mechanisms that dictate the form and function of normal cilia are not entirely understood, but it is clear that ciliary dysfunction results in impaired respiratory defense. METHODS A literature review of the current knowledge of cilia dysfunction in chronic rhinosinsusitis was conducted. RESULTS Ciliary dysfunction may be primary, the result of genetic mutations resulting in abnormal cilia structure, or, more commonly, secondary, the result of environmental, infectious, or inflammatory stimuli that disrupt normal motility or coordination. Patients with chronic rhinosinusitis (CRS) have been found to have impaired mucociliary clearance. Many biochemical, environmental, and mechanical stimuli have been shown to influence ciliary beat frequency, and common microbial pathogens of respiratory mucosa such as Pseudomonas aeruginosa and Haemophilus influenzae have developed toxins that appear to interrupt normal mucociliary function. Furthermore, inflammatory mediators known to be present in patients with CRS appear to impair secondarily mucociliary clearance. CONCLUSION The goal of this article is to summarize the recent developments in the understanding of cilia dysfunction and mucociliary clearance in CRS.
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Affiliation(s)
- David Gudis
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, 3400 Spruce Street, Philadelphia, PA 19104, USA
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Bailey KL, LeVan TD, Yanov DA, Pavlik JA, DeVasure JM, Sisson JH, Wyatt TA. Non-typeable Haemophilus influenzae decreases cilia beating via protein kinase Cε. Respir Res 2012; 13:49. [PMID: 22712879 PMCID: PMC3487807 DOI: 10.1186/1465-9921-13-49] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 05/24/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Haemophilus influenzae infection of the nasal epithelium has long been associated with observations of decreased nasal ciliary beat frequency (CBF) and injury to the ciliated epithelium. Previously, we have reported that several agents that slow CBF also have the effect of activating protein kinase C epsilon (PKCε) activity in bronchial epithelial cells. The subsequent auto-downregulation of PKCε or the direct inhibition of PKCε leads to the specific detachment of the ciliated cells. METHODS Primary cultures of ciliated bovine bronchial epithelial cells were exposed to filtered conditioned media supernatants from non-typeable H. influenzae (NTHi) cultures. CBF and motile points were measured and PKCε activity assayed. RESULTS NTHi supernatant exposure significantly and rapidly decreased CBF in a dose-dependent manner within 10 minutes of exposure. After 3 hours of exposure, the number of motile ciliated cells significantly decreased. Direct measurement of PKCε activity revealed a dose-dependent activation of PKCε in response to NTHi supernatant exposure. Both CBF and PKCε activity changes were only observed in fresh NTHi culture supernatant and not observed in exposures to heat-inactivated or frozen supernatants. CONCLUSIONS Our results suggest that CBF slowing observed in response to NTHi is consistent with the stimulated activation of PKCε. Ciliated cell detachment is associated with PKCε autodownregulation.
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Affiliation(s)
- Kristina L Bailey
- Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, 985300 Nebraska Medical Center, Omaha, NE, 68198-5300, USA
| | - Tricia D LeVan
- VA Nebraska-Western Iowa Health Care System Research Service, Department of Veterans Affairs Medical Center, 4101 Woolworth Avenue, Omaha, NE, 68105, USA
- Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, 985300 Nebraska Medical Center, Omaha, NE, 68198-5300, USA
- Department of Epidemiology, College of Public Health, University of Nebraska Medical Center, Omaha, NE, 68198-5910, USA
| | - Daniel A Yanov
- Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, 985300 Nebraska Medical Center, Omaha, NE, 68198-5300, USA
| | - Jaqueline A Pavlik
- Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, 985300 Nebraska Medical Center, Omaha, NE, 68198-5300, USA
| | - Jane M DeVasure
- Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, 985300 Nebraska Medical Center, Omaha, NE, 68198-5300, USA
| | - Joseph H Sisson
- Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, 985300 Nebraska Medical Center, Omaha, NE, 68198-5300, USA
| | - Todd A Wyatt
- VA Nebraska-Western Iowa Health Care System Research Service, Department of Veterans Affairs Medical Center, 4101 Woolworth Avenue, Omaha, NE, 68105, USA
- Department of Environmental, Agricultural, and Occupational Health, College of Public Health, University of Nebraska Medical Center, Omaha, NE, 68198-5910, USA
- Pulmonary, Critical Care, Sleep & Allergy Division, Department of Internal Medicine, 985300 Nebraska Medical Center, Omaha, NE, 68198-5300, USA
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Abstract
Pneumococcal meningitis continues to be associated with high rates of mortality and long-term neurological sequelae. The most common route of infection starts by nasopharyngeal colonization by Streptococcus pneumoniae, which must avoid mucosal entrapment and evade the host immune system after local activation. During invasive disease, pneumococcal epithelial adhesion is followed by bloodstream invasion and activation of the complement and coagulation systems. The release of inflammatory mediators facilitates pneumococcal crossing of the blood-brain barrier into the brain, where the bacteria multiply freely and trigger activation of circulating antigen-presenting cells and resident microglial cells. The resulting massive inflammation leads to further neutrophil recruitment and inflammation, resulting in the well-known features of bacterial meningitis, including cerebrospinal fluid pleocytosis, cochlear damage, cerebral edema, hydrocephalus, and cerebrovascular complications. Experimental animal models continue to further our understanding of the pathophysiology of pneumococcal meningitis and provide the platform for the development of new adjuvant treatments and antimicrobial therapy. This review discusses the most recent views on the pathophysiology of pneumococcal meningitis, as well as potential targets for (adjunctive) therapy.
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Popova TG, Millis B, Chung MC, Bailey C, Popov SG. Anthrolysin O and fermentation products mediate the toxicity of Bacillus anthracis to lung epithelial cells under microaerobic conditions. ACTA ACUST UNITED AC 2010; 61:15-27. [PMID: 20946354 PMCID: PMC3040846 DOI: 10.1111/j.1574-695x.2010.00740.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Bacillus anthracis generates virulence factors such as lethal and edema toxins, capsule, and hemolytic proteins under conditions of reduced oxygenation. Here, we report on the acute cytotoxicity of culture supernatants (Sups) of six nonencapsulated B. anthracis strains grown till the stationary phase under static microaerobic conditions. Human small airway epithelial, umbilical vein endothelial, Caco-2, and Hep-G2 cells were found to be susceptible. Sups displayed a reduction of pH to 5.3–5.5, indicating the onset of acid anaerobic fermentation; however, low pH itself was not a major factor of toxicity. The pore-forming hemolysin, anthrolysin O (ALO), contributed to the toxicity in a concentration-dependent manner. Its effect was found to be synergistic with a metabolic product of B. anthracis, succinic acid. Cells exposed to Sups demonstrated cytoplasmic membrane blebbing, increased permeability, loss of ATP, mitochondrial membrane potential collapse, and arrest of cell respiration. The toxicity was reduced by inhibition of ALO by cholesterol, decomposition of reactive oxygen species, and inhibition of mitochondrial succinate dehydrogenase. Cell death appears to be caused by an acute primary membrane permeabilization by ALO, followed by a burst of reactive radicals from the mitochondria fuelled by the succinate, which is generated by bacteria in the hypoxic environment. This mechanism of metabolic toxicity is relevant to the late-stage conditions of hypoxia and acidosis found in anthrax patients and might operate at anatomical locations of the host deprived from oxygen supply.
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Affiliation(s)
- Taissia G Popova
- National Center for Biodefense and Infectious Diseases, George Mason University, Manassas, VA, USA
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33
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Abstract
Cilia are complex and powerful cellular structures that serve a multitude of functions across many types of organisms. In humans, one of the most critical roles of cilia is defense of the airway. The respiratory epithelium is lined with cilia that normally carry out an integrated and coordinated mechanism called mucociliary clearance. Mucociliary clearance, the process by which cilia transport the viscous mucus blanket of the upper airway to the gastrointestinal tract, is the primary means by which the upper airway clears itself of pathogens, allergens, debris, and toxins. The complex structure and regulatory mechanisms that dictate the form and function of normal cilia are not entirely understood, but it is clear that ciliary dysfunction results in impaired respiratory defense. Ciliary dysfunction may be primary, the result of genetic mutations resulting in abnormal cilia structure, or secondary, the result of environmental, infectious or inflammatory stimuli that disrupt normal motility or coordination.
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Affiliation(s)
- David A Gudis
- Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania, Ravdin Building, 5th Floor, 3400 Spruce Street, Philadelphia, PA 19104, USA
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Weiser JN. The pneumococcus: why a commensal misbehaves. J Mol Med (Berl) 2009; 88:97-102. [PMID: 19898768 DOI: 10.1007/s00109-009-0557-x] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Revised: 10/14/2009] [Accepted: 10/19/2009] [Indexed: 10/20/2022]
Abstract
Several characteristics of Streptococcus pneumoniae (pneumococcus) combine to make it a particularly problematic pathogen. Firstly, the pneumococcus has the capacity to cause disease through the expression of virulence factors such as its polysaccharide capsule and pore-forming toxin. In addition, the pneumococcus is highly adaptable as demonstrated by its ability to acquire and disseminate resistance to multiple antibiotics. Although the pneumococcus is a major cause of disease, the organism is most commonly an "asymptomatic" colonizer of its human host (the carrier state), with transmission occurring exclusively from this reservoir of commensal organisms. Thus, it is unclear how the organism's virulence and adaptability promote its persistence or host to host spread during its carrier state. This review summarizes current understanding of how these characteristics may contribute to the commensal lifestyle of the pneumococcus.
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Affiliation(s)
- Jeffrey N Weiser
- Department of Microbiology and Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, 19104, USA.
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Orihuela CJ, Fillon S, Smith-Sielicki SH, El Kasmi KC, Gao G, Soulis K, Patil A, Murray PJ, Tuomanen EI. Cell wall-mediated neuronal damage in early sepsis. Infect Immun 2006; 74:3783-9. [PMID: 16790750 PMCID: PMC1489725 DOI: 10.1128/iai.00022-06] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Neuronal dysfunction can occur in the course of sepsis without meningitis. Sepsis-associated neuronal damage (SAND) was observed in the hippocampus within hours in experimental pneumococcal bacteremia. Intravascular challenge with purified bacterial cell wall recapitulated SAND. SAND persisted in PAFr(-/-) mice but was partially mitigated in mice lacking cell wall recognition proteins TLR2 and Nod2 and in mice overexpressing interleukin-10 (IL-10) in macrophages. Thus, cell wall drives SAND through IL-10-repressible inflammatory events. Treatment with CDP-choline ameliorated SAND, suggesting that it may be an effective adjunctive therapy to increase survival and reduce organ damage in sepsis.
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Affiliation(s)
- Carlos J Orihuela
- Infectious Diseases, St. Jude Children's Research Hospital, Mailstop 320 IRC 8057, 332 N. Lauderdale Rd., Memphis, TN 38105, USA
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Regev-Yochay G, Trzcinski K, Thompson CM, Malley R, Lipsitch M. Interference between Streptococcus pneumoniae and Staphylococcus aureus: In vitro hydrogen peroxide-mediated killing by Streptococcus pneumoniae. J Bacteriol 2006; 188:4996-5001. [PMID: 16788209 PMCID: PMC1482988 DOI: 10.1128/jb.00317-06] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The bactericidal activity of Streptococcus pneumoniae toward Staphylococcus aureus is mediated by hydrogen peroxide. Catalase eliminated this activity. Pneumococci grown anaerobically or genetically lacking pyruvate oxidase (SpxB) were not bactericidal, nor were nonpneumococcal streptococci. These results provide a possible mechanistic explanation for the interspecies interference observed in epidemiologic studies.
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Affiliation(s)
- Gili Regev-Yochay
- Department of Epidemiology, Harvard School of Public Health, 677 Huntington Ave., Boston, MA 02115, USA.
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Feldman C, Cockeran R, Jedrzejas MJ, Mitchell TJ, Anderson R. Hyaluronidase augments pneumolysin-mediated injury to human ciliated epithelium. Int J Infect Dis 2006; 11:11-5. [PMID: 16483814 DOI: 10.1016/j.ijid.2005.09.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2005] [Revised: 08/01/2005] [Accepted: 09/08/2005] [Indexed: 10/25/2022] Open
Abstract
OBJECTIVES The main objective of this study was to investigate the effects of pneumococcal hyaluronidase (0.1-10microg/ml), alone and in combination with pneumolysin (50 and 100ng/ml), on human ciliated epithelium. METHODS Ciliary beat frequency (CBF) and structural integrity of human ciliated respiratory epithelium in vitro were studied using a phototransistor technique and a visual scoring index, respectively. RESULTS Hyaluronidase per se did not affect either CBF or the structural integrity of the epithelium. However, preincubation of the epithelial strips with hyaluronidase (10microg/ml) for 30min at 37 degrees C significantly potentiated pneumolysin-mediated ciliary slowing and epithelial damage. Hyaluronan, a substrate of hyaluronidase, had no effects on the ciliated respiratory epithelium in concentrations up to 100microg/ml and did not antagonize the injurious effects of pneumolysin on the epithelium. However, preincubation of the epithelial strips with hyaluronan (100microg/ml) was associated with attenuation of the ciliary slowing and epithelial damage induced by incubation of the strips with hyaluronidase (10microg/ml) for 30min at 37 degrees C followed by addition of pneumolysin (50ng/ml). CONCLUSIONS Although having no direct effects alone, hyaluronidase may contribute to pneumolysin-mediated damage and dysfunction to respiratory epithelium, thereby favoring colonization and subsequently extra-pulmonary dissemination of the pneumococcus.
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Affiliation(s)
- C Feldman
- Division of Pulmonology, Department of Medicine, Johannesburg Hospital and University of the Witwatersrand, 7 York Road, Parktown, 2193 Johannesburg, South Africa.
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Orihuela CJ, Fogg G, DiRita VJ, Tuomanen E. Bacterial Interactions with Mucosal Epithelial Cells. Mucosal Immunol 2005. [DOI: 10.1016/b978-012491543-5/50044-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Cockeran R, Anderson R, Feldman C. Pneumolysin in the immunopathogenesis and treatment of pneumococcal disease. Expert Rev Anti Infect Ther 2004; 1:231-9. [PMID: 15482118 DOI: 10.1586/14787210.1.2.231] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recent insights into the immunopathogenesis of pneumococcal infection, a common and significant cause of morbidity and mortality, have implicated pneumolysin as being a prominent virulence factor, which may play a role in microbial colonization, invasion and dissemination, as well as tissue inflammation. Being a highly immunogenic polypeptide produced by all clinically relevant pneumococcal isolates, pneumolysin is recognized as a potential carrier protein for polysaccharide conjugate vaccines, while in the setting of acute disease, promising pneumolysin-directed pharmacological strategies include, among others, macrolides and corticosteroids.
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Abstract
Infection begins when microorganisms overcome host barriers and multiply within host tissues. To contain the infection, the host mounts an inflammatory response that mobilizes defense systems and kills the invading microorganisms. A focal inflammatory response is usually sufficient to eradicate the organisms. However, when it fails to contain the infection, the organisms, their toxins, and numerous host mediators are released into the bloodstream, producing a systemic inflammatory response and organ failure. Microorganisms have coevolved with their hosts, thereby acquiring means of overcoming host defense mechanisms or even taking advantage of innate host responses. Many pathogens avoid recognition by the host or dampen host immune responses via sophisticated pathogen-host interactions. Some pathogens benefit from the inflammatory response. According to current hypotheses regarding the pathogenesis of sepsis, the host generates both an innate immune response identical for all pathogens and an adaptive pathogen-specific response. Determining whether the innate response benefits the pathogen or the host is essential for understanding host-pathogen interactions. In this review, we discuss how pathogens interfere with innate and adaptive immune responses to escape eradication by the host.
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Affiliation(s)
- Pierre Moine
- Department of Anesthesiology, University Hospital, University of Colorado Health Sciences Center, Denver, Colorado 80626, USA.
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Cockeran R, Theron AJ, Feldman C, Mitchel TJ, Anderson R. Pneumolysin potentiates oxidative inactivation of alpha-1-proteinase inhibitor by activated human neutrophils. Respir Med 2004; 98:865-71. [PMID: 15338799 DOI: 10.1016/j.rmed.2004.02.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This study was designed to investigate the effects of the Streptococcus pneumoniae-derived, pro-inflammatory toxin, pneumolysin (8.37 and 41.75 ng/ml), on the oxidative inactivation of alpha-1-protease inhibitor (API) by chemoattractant-activated human neutrophils in vitro. The elastase inhibitory capacity (EIC) of API in supernatants from unstimulated neutrophils, neutrophils treated with pneumolysin only, or with the chemoattractant FMLP (1 microM) only, or the combination of the toxin with FMLP was measured by a colorimetric procedure based on the activity of added porcine elastase. The EIC of API was unaffected by exposure to pneumolysin only, unstimulated neutrophils, or neutrophils treated with pneumolysin only. However, exposure to FMLP-activated neutrophils resulted in a reduction of the EIC of API, which was significantly (P<0.05) augmented by pneumolysin (mean reductions of 16%, 43% and 83% for FMLP only and in combination with 8.37 and 41.75 ng/ml pneumolysin, respectively), and was attenuated by wortmannin (1 microM), an inhibitor of NADPH oxidase, the oxidant-scavenger methionine (100 microM), and depletion of Ca2+ from the cell-suspending medium. These pro-proteolytic interactions of pneumolysin with chemoattractant-activated neutrophils may contribute to the invasiveness of the pneumococcus.
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Affiliation(s)
- Riana Cockeran
- MRC Unit for Inflammation and Immunity, Department of Immunology, Faculty of Health Sciences, University of Pretoria and Tshwane Academic Division of the National Health Laboratory Services, PO Box 2034, Pretoria 0001, South Africa
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García-Suárez MDM, Cima-Cabal MD, Flórez N, García P, Cernuda-Cernuda R, Astudillo A, Vázquez F, De los Toyos JR, Méndez FJ. Protection against pneumococcal pneumonia in mice by monoclonal antibodies to pneumolysin. Infect Immun 2004; 72:4534-40. [PMID: 15271913 PMCID: PMC470670 DOI: 10.1128/iai.72.8.4534-4540.2004] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pneumolysin (PLY) is an important virulence factor of Streptococcus pneumoniae. We examined the ability of three murine monoclonal antibodies (MAbs) to PLY (PLY-4, PLY-5, and PLY-7) to affect the course of pneumococcal pneumonia in mice. The intravenous administration of antibodies PLY-4 and PLY-7 protected the mice from the lethal effect of the purified toxin. Mice treated with PLY-4 before intranasal inoculation of S. pneumoniae type 2 survived longer (median survival time, 100 h) than did untreated animals (median survival time, 60 h) (P < 0.0001). The median survival time for mice treated with a combination of PLY-4 and PLY-7 was 130 h, significantly longer than that for mice given isotype-matched indifferent MAbs (P = 0.0288) or nontreated mice (P = 0.0002). The median survival time for mice treated with a combination of three MAbs was significantly longer (>480 h) than that for mice treated with PLY-5 (48 h; P < 0.0001), PLY-7 (78 h; P = 0.0007), or PLY-4 (100 h; P = 0.0443) alone. Similarly, the survival rate for mice treated with three MAbs (10 of 20 mice) was significantly higher than the survival rate obtained with PLY-5 (1 of 20; P = 0.0033), PLY-4 (2 of 20; P = 0.0138), or PLY-7 (3 of 20; P = 0.0407) alone. These results suggest that anti-PLY MAbs act with a synergistic effect. Furthermore, MAb administration was associated with a significant decrease in bacterial lung colonization and lower frequencies of bacteremia and tissue injury with respect to the results for the control groups.
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Spreer A, Lis A, Gerber J, Reinert RR, Eiffert H, Nau R. Differences in clinical manifestation of Streptococcus pneumoniae infection are not correlated with in vitro production and release of the virulence factors pneumolysin and lipoteichoic and teichoic acids. J Clin Microbiol 2004; 42:3342-5. [PMID: 15243112 PMCID: PMC446287 DOI: 10.1128/jcm.42.7.3342-3345.2004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Production and release of the pneumococcal virulence factors pneumolysin and lipoteichoic and teichoic acid in 75 clinical isolates were investigated. No difference was found between strains causing systemic infection or localized respiratory infection and isolates from asymptomatic carriers. This suggests that the presence of pneumolysin and lipoteichoic and teichoic acid is a necessary but not a sufficient condition for pneumococcal infection and development of invasive disease.
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Affiliation(s)
- Annette Spreer
- Department of Neurology, University of Göttingen, Germany
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Bolm M, Jansen WTM, Schnabel R, Chhatwal GS. Hydrogen peroxide-mediated killing of Caenorhabditis elegans: a common feature of different streptococcal species. Infect Immun 2004; 72:1192-4. [PMID: 14742574 PMCID: PMC321644 DOI: 10.1128/iai.72.2.1192-1194.2004] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recently, we reported that Streptococcus pyogenes kills Caenorhabditis elegans by the use of hydrogen peroxide (H2O2). Here we show that diverse streptococcal species cause death of C. elegans larvae in proportion to the level of H2O2 produced. H2O2 may mask the effects of other pathogenicity factors of catalase-negative bacteria in the C. elegans infection model.
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Affiliation(s)
- Maike Bolm
- GBF--German Research Centre for Biotechnology, 38124 Braunschweig, Germany.
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