1
|
Ostermann L, Seeliger B, David S, Flasche C, Maus R, Reinboth MS, Christmann M, Neumann K, Brand K, Seltmann S, Bühling F, Paton JC, Roth J, Vogl T, Viemann D, Welte T, Maus UA. S100A9 is indispensable for survival of pneumococcal pneumonia in mice. PLoS Pathog 2023; 19:e1011493. [PMID: 37467233 DOI: 10.1371/journal.ppat.1011493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 06/18/2023] [Indexed: 07/21/2023] Open
Abstract
S100A8/A9 has important immunomodulatory roles in antibacterial defense, but its relevance in focal pneumonia caused by Streptococcus pneumoniae (S. pneumoniae) is understudied. We show that S100A9 was significantly increased in BAL fluids of patients with bacterial but not viral pneumonia and correlated with procalcitonin and sequential organ failure assessment scores. Mice deficient in S100A9 exhibited drastically elevated Zn2+ levels in lungs, which led to bacterial outgrowth and significantly reduced survival. In addition, reduced survival of S100A9 KO mice was characterized by excessive release of neutrophil elastase, which resulted in degradation of opsonophagocytically important collectins surfactant proteins A and D. All of these features were attenuated in S. pneumoniae-challenged chimeric WT→S100A9 KO mice. Similarly, therapy of S. pneumoniae-infected S100A9 KO mice with a mutant S100A8/A9 protein showing increased half-life significantly decreased lung bacterial loads and lung injury. Collectively, S100A9 controls central antibacterial immune mechanisms of the lung with essential relevance to survival of pneumococcal pneumonia. Moreover, S100A9 appears to be a promising biomarker to distinguish patients with bacterial from those with viral pneumonia. Trial registration: Clinical Trials register (DRKS00000620).
Collapse
Affiliation(s)
- Lena Ostermann
- Division of Experimental Pneumology, Hannover Medical School, Hannover, Germany
| | - Benjamin Seeliger
- Clinic for Pneumology, Hannover Medical School, Hannover, Germany
- German Center for Lung Research, Hannover, Germany
| | - Sascha David
- Institute of Intensive Care Medicine, University Hospital Zurich, Zurich, Switzerland
| | - Carolin Flasche
- Division of Experimental Pneumology, Hannover Medical School, Hannover, Germany
| | - Regina Maus
- Division of Experimental Pneumology, Hannover Medical School, Hannover, Germany
| | - Marieke S Reinboth
- Division of Experimental Pneumology, Hannover Medical School, Hannover, Germany
| | - Martin Christmann
- Institute of Clinical Chemistry, Hannover Medical School, Hannover, Germany
| | - Konstantin Neumann
- Institute of Clinical Chemistry, Hannover Medical School, Hannover, Germany
| | - Korbinian Brand
- Institute of Clinical Chemistry, Hannover Medical School, Hannover, Germany
| | | | - Frank Bühling
- Labopart Medical Laboratories, Dresden and Chemnitz, Germany
| | - James C Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, Adelaide, Australia
| | - Johannes Roth
- Institute of Immunology, University of Münster, Münster, Germany
| | - Thomas Vogl
- Institute of Immunology, University of Münster, Münster, Germany
| | - Dorothee Viemann
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
- Translational Pediatrics, Department of Pediatrics, University Hospital Würzburg, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
- Center for Infection Research, University Würzburg, Germany
| | - Tobias Welte
- Clinic for Pneumology, Hannover Medical School, Hannover, Germany
- German Center for Lung Research, Hannover, Germany
| | - Ulrich A Maus
- Division of Experimental Pneumology, Hannover Medical School, Hannover, Germany
- German Center for Lung Research, Hannover, Germany
| |
Collapse
|
2
|
T'Jonck W, Bain CC. The role of monocyte-derived macrophages in the lung: it's all about context. Int J Biochem Cell Biol 2023; 159:106421. [PMID: 37127181 DOI: 10.1016/j.biocel.2023.106421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 04/24/2023] [Accepted: 04/28/2023] [Indexed: 05/03/2023]
Abstract
Macrophages are present in every tissue of the body where they play crucial roles in maintaining tissue homeostasis and providing front line defence against pathogens. Arguably, this is most important at mucosal barrier tissues, such as the lung and gut, which are major ports of entry for pathogens. However, a common feature of inflammation, infection or injury is the loss of tissue resident macrophages and accumulation of monocytes from the circulation, which differentiate, to different extents, into macrophages. The exact fate and function of these elicited, monocyte-derived macrophages in infection, injury and inflammation remains contentious. While some studies have documented the indispensable nature of monocytes and their macrophage derivatives in combatting infection and restoration of lung homeostasis following insult, observations from clinical studies and preclinical models of lung infection/injury shows that monocytes and their progeny can become dysregulated in severe pathology, often perpetuating rather than resolving the insult. In this Mini Review, we aim to bring together these somewhat contradictory reports by discussing how the plasticity of monocytes allow them to assume distinct functions in different contexts in the lung, from health to infection, and effective tissue repair to fibrotic disease.
Collapse
Affiliation(s)
- Wouter T'Jonck
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, Edinburgh BioQuarter, EH16 4TJ, U.K; Institute for Regeneration and Repair, University of Edinburgh, Edinburgh BioQuarter
| | - Calum C Bain
- University of Edinburgh Centre for Inflammation Research, Queen's Medical Research Institute, Edinburgh BioQuarter, EH16 4TJ, U.K; Institute for Regeneration and Repair, University of Edinburgh, Edinburgh BioQuarter
| |
Collapse
|
3
|
Periselneris J, Turner CT, Ercoli G, Szylar G, Weight CM, Thurston T, Whelan M, Tomlinson G, Noursadeghi M, Brown J. Pneumolysin suppresses the initial macrophage pro-inflammatory response to Streptococcus pneumoniae. Immunology 2022; 167:413-427. [PMID: 35835695 PMCID: PMC10497322 DOI: 10.1111/imm.13546] [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: 01/10/2022] [Accepted: 07/04/2022] [Indexed: 12/01/2022] Open
Abstract
Published data for the Streptococcus pneumoniae virulence factor Pneumolysin (Ply) show contradictory effects on the host inflammatory response to infection. Ply has been shown to activate the inflammasome, but also can bind to MRC-1 resulting in suppression of dendritic cell inflammatory responses. We have used an in vitro infection model of human monocyte-derived macrophages (MDM), and a mouse model of pneumonia to clarify whether pro- or anti-inflammatory effects dominate the effects of Ply on the initial macrophage inflammatory response to S. pneumoniae, and the consequences during early lung infection. We found that infection with S. pneumoniae expressing Ply suppressed tumour necrosis factor (TNF) and interleukin-6 production by MDMs compared to cells infected with ply-deficient S. pneumoniae. This effect was independent of bacterial effects on cell death. Transcriptional analysis demonstrated S. pneumoniae expressing Ply caused a qualitatively similar but quantitatively lower MDM transcriptional response to S. pneumoniae compared to ply-deficient S. pneumoniae, with reduced expression of TNF and type I IFN inducible genes. Reduction of the MDM inflammatory response was prevented by inhibition of SOCS1. In the early lung infection mouse model, the TNF response to ply-deficient S. pneumoniae was enhanced and bacterial clearance increased compared to infection with wild-type S. pneumoniae. Overall, these data show Ply inhibits the initial macrophage inflammatory response to S. pneumoniae, probably mediated through SOCS1, and this was associated with improved immune evasion during early lung infection.
Collapse
Affiliation(s)
- Jimstan Periselneris
- Centre for Inflammation and Tissue Repair, Division of MedicineUniversity College Medical SchoolLondonUK
| | | | - Giuseppe Ercoli
- Centre for Inflammation and Tissue Repair, Division of MedicineUniversity College Medical SchoolLondonUK
| | - Gabriella Szylar
- Centre for Inflammation and Tissue Repair, Division of MedicineUniversity College Medical SchoolLondonUK
| | | | - Teresa Thurston
- MRC Centre for Molecular Bacteriology and InfectionImperial College LondonLondonUK
| | - Matthew Whelan
- Division of Infection and ImmunityUniversity College LondonLondonUK
| | | | | | - Jeremy Brown
- Centre for Inflammation and Tissue Repair, Division of MedicineUniversity College Medical SchoolLondonUK
| |
Collapse
|
4
|
Pereira JM, Xu S, Leong JM, Sousa S. The Yin and Yang of Pneumolysin During Pneumococcal Infection. Front Immunol 2022; 13:878244. [PMID: 35529870 PMCID: PMC9074694 DOI: 10.3389/fimmu.2022.878244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 03/23/2022] [Indexed: 12/15/2022] Open
Abstract
Pneumolysin (PLY) is a pore-forming toxin produced by the human pathobiont Streptococcus pneumoniae, the major cause of pneumonia worldwide. PLY, a key pneumococcal virulence factor, can form transmembrane pores in host cells, disrupting plasma membrane integrity and deregulating cellular homeostasis. At lytic concentrations, PLY causes cell death. At sub-lytic concentrations, PLY triggers host cell survival pathways that cooperate to reseal the damaged plasma membrane and restore cell homeostasis. While PLY is generally considered a pivotal factor promoting S. pneumoniae colonization and survival, it is also a powerful trigger of the innate and adaptive host immune response against bacterial infection. The dichotomy of PLY as both a key bacterial virulence factor and a trigger for host immune modulation allows the toxin to display both "Yin" and "Yang" properties during infection, promoting disease by membrane perforation and activating inflammatory pathways, while also mitigating damage by triggering host cell repair and initiating anti-inflammatory responses. Due to its cytolytic activity and diverse immunomodulatory properties, PLY is integral to every stage of S. pneumoniae pathogenesis and may tip the balance towards either the pathogen or the host depending on the context of infection.
Collapse
Affiliation(s)
- Joana M. Pereira
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Molecular and Cellular (MC) Biology PhD Program, ICBAS - Instituto de Ciência Biomédicas Abel Salazar, University of Porto, Porto, Portugal
| | - Shuying Xu
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, United States
- Graduate Program in Immunology, Tufts Graduate School of Biomedical Sciences, Boston, MA, United States
| | - John M. Leong
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, United States
| | - Sandra Sousa
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| |
Collapse
|
5
|
Golden TN, Venosa A, Gow AJ. Cell Origin and iNOS Function Are Critical to Macrophage Activation Following Acute Lung Injury. Front Pharmacol 2022; 12:761496. [PMID: 35145401 PMCID: PMC8822172 DOI: 10.3389/fphar.2021.761496] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 12/09/2021] [Indexed: 01/19/2023] Open
Abstract
In the intratracheal bleomycin (ITB) model of acute lung injury (ALI), macrophages are recruited to the lung and participate in the inflammation and resolution that follows injury. Macrophage origin is influential in determining activation; however, the specific phenotype of recruited and resident macrophages is not known. Inducible nitric oxide synthase (iNOS) has been implicated in the pathogenesis of ALI; however, the effects of its inhibition are mixed. Here we examined how macrophage origin determines the phenotypic response to ALI. Further, we hypothesize cell specific iNOS is key to determining activation and recruitment. Using a chimeric mouse approach, we have identified recruited and resident macrophage populations. We also used the chimeric mouse approach to create either pulmonary or bone marrow NOS2-/- mice and systemically inhibited iNOS via 1400 W. We evaluated macrophage populations at the peak of inflammation (8 days) and the beginning of resolution (15 days) following ITB. These studies demonstrate tissue resident macrophages adopt a M2 phenotype specifically, but monocyte originated macrophages activate along a spectrum. Additionally, we demonstrated that monocyte originating macrophage derived iNOS is responsible for recruitment to the lung during the inflammatory phase. Further, we show that macrophage activation is dependent upon cellular origin. Finally, these studies suggest pulmonary derived iNOS is detrimental to the lung following ITB. In conclusion, macrophage origin is a key determinant in response to ALI and iNOS is central to recruitment and activation.
Collapse
Affiliation(s)
- Thea N. Golden
- Center for Research on Reproduction and Women’s Health, School of Medicine, University of Pennsylvania, Philadelphia, PA, United States,Center for Excellence in Environmental Toxicology, School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Alessandro Venosa
- Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, UT, United States
| | - Andrew J Gow
- Department of Pharmacology and Toxicology, Rutgers, The State University of New Jersey, Piscataway, NJ, United States,*Correspondence: Andrew J Gow,
| |
Collapse
|
6
|
Yoon HY, Moon SJ, Song JW. Lung Tissue Microbiome Is Associated With Clinical Outcomes of Idiopathic Pulmonary Fibrosis. Front Med (Lausanne) 2021; 8:744523. [PMID: 34733866 PMCID: PMC8559550 DOI: 10.3389/fmed.2021.744523] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 09/20/2021] [Indexed: 12/26/2022] Open
Abstract
Background: Several studies using bronchoalveolar lavage fluid (BALF) reported that lung microbial communities were associated with the development and clinical outcome of idiopathic pulmonary fibrosis (IPF). However, the microbial communities in IPF lung tissues are not well known. This study is aimed to investigate bacterial microbial communities in lung tissues and determine their impact on the clinical outcomes of patients with IPF. Methods: Genomic DNA extracted from lung tissues of patients with IPF (n = 20; 10 non-survivors) and age- and sex-matched controls (n = 20) was amplified using fusion primers targeting the V3 and V4 regions of the 16S RNA genes with indexing barcodes. Results: Mean age of IPF subjects was 63.3 yr, and 65% were male. Alpha diversity indices did not significantly differ between IPF patients and controls, or between IPF non-survivors and survivors. The relative abundance of Lactobacillus, Paracoccus, and Akkermansia was increased, whereas that of Caulobacter, Azonexus, and Undibacterium decreased in patients with IPF compared with that in the controls. A decreased relative abundance of Pelomonas (odds ratio [OR], 0.352, p = 0.027) and Azonexus (OR, 0.013, p = 0.046) was associated with a diagnosis of IPF in the multivariable logistic analysis adjusted by age and gender. Multivariable Cox analysis adjusted for age and forced vital capacity (FVC) revealed that higher relative abundance of Streptococcus (hazard ratio [HR], 1.993, p = 0.044), Sphingomonas (HR, 57.590, p = 0.024), and Clostridium (HR, 37.189, p = 0.038) was independently associated with IPF mortality. The relative abundance of Curvibacter (r = 0.590) and Thioprofundum (r = 0.373) was correlated positively, whereas that of Anoxybacillus (r = -0.509) and Enterococcus (r = -0.593) was correlated inversely with FVC. In addition, the relative abundance of the Aquabacterium (r = 0.616) and Peptoniphilus (r = 0.606) genera was positively correlated, whereas that of the Fusobacterium (r = -0.464) and Phycicoccus (r = -0.495) genera was inversely correlated with distance during the 6-min walking test. Conclusions: The composition of the microbiome in lung tissues differed between patients with IPF and controls and was associated with the diagnosis, mortality, and disease severity of IPF.
Collapse
Affiliation(s)
- Hee-Young Yoon
- Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Su-Jin Moon
- Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Jin Woo Song
- Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| |
Collapse
|
7
|
Zinserling VA, Swistunov VV, Botvinkin AD, Stepanenko LA, Makarova AE. Lobar (croupous) pneumonia: old and new data. Infection 2021; 50:235-242. [PMID: 34472009 PMCID: PMC8409273 DOI: 10.1007/s15010-021-01689-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 08/23/2021] [Indexed: 01/20/2023]
Abstract
Background and aim Pneumonia remains one of the most frequent death causes worldwide. Among the etiological factors S. pneumoniae-causing lobar pneumonia plays a leading role. According to current textbook knowledge at least three sequential stages of lobar pneumonia are distinguished: congestion, red hepatization and gray hepatization. However, there are no detailed data supporting this stage concept. There are also controversial views on its etiology. In this study, the lung changes in lobar pneumonia were related to the cause and duration of the disease. In addition, the complications of the disease were evaluated. PCR studies verified the etiology of pneumonia. Material and methods Lobar pneumonia was analyzed in 252 post mortem cases examined in a large hospital in Irkutsk. The pathology, etiology of pneumonia, course of disease and cause of death were recorded and correlated to its clinical course and duration. In the second part of the study, the results in 95 patients were analyzed in detail and related to PCR findings. Results Most patients were adult men of low social status who showed signs of severe alcoholism. Lobar pneumonia was observed in 85% of the patients, while the remaining patients showed sublobar (“lobular”, focal) lung involvement. Histologically, three patterns of inflammation were observed, which in most patients occurred concurrently in different parts of the involved lobe: “congestion”, characterized by serous exudation with multiple cocci (41% of cases), “red hepatization” (41% of cases) and “gray hepatization” (100% of cases). The latter pattern was subdivided into three subgroups according to the ratio of fibrin—neutrophils and the presence of macrophages. The mean number of different histological patterns observed per patient was 3.8. There was no correlation between the inflammatory patterns and the duration of the disease. In 23% of the patients, the cause of death was of pulmonary origin, while the remaining patients died of extrapulmonary complications (i.e. acute heart failure 26%, acute vascular insufficiency 15% purulent meningitis 11–24.3%. In 29/95 patients (20 with lobar and 9 with focal pneumonia) pneumococcal etiology of pneumonia was established by PCR. Conclusion Lobar pneumonia is a distinct clinico-pathological entity caused by S. pneumoniae, demonstrated by PCR testing and/or cytological examinations. Bacteriologic studies frequently give falsenegative results. Lobar pneumonia is characterized by three main histopathological patterns (congestion or microbeous edema, and red and gray hepatization) which usually occur side by side and not in chronological order. Early death is often related to heart failure and septic shock, while meningitis is a frequent complication later in the course.
Collapse
Affiliation(s)
- Vsevolod A Zinserling
- Department of Pathomorphology, Institute of Experimental Medicine, V.A. Almazov Research Center, Saint Petersburg, Russia. .,Center of Infectious Pathology, S.P. Botkin Infectious Hospital, Saint-Petersburg, Russia.
| | - Vladimir V Swistunov
- Irkutsk's Cities Municipal Hospital, Irkutsk, Russia.,Irkutsk Medical University, Irkutsk, Russia
| | | | | | - Angelica E Makarova
- Irkutsk's Cities Municipal Hospital, Irkutsk, Russia.,Irkutsk Medical University, Irkutsk, Russia
| |
Collapse
|
8
|
Streptococcus pneumoniae and Its Virulence Factors H 2O 2 and Pneumolysin Are Potent Mediators of the Acute Chest Syndrome in Sickle Cell Disease. Toxins (Basel) 2021; 13:toxins13020157. [PMID: 33671422 PMCID: PMC7922783 DOI: 10.3390/toxins13020157] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/08/2021] [Accepted: 02/11/2021] [Indexed: 01/27/2023] Open
Abstract
Sickle cell disease (SCD) is one of the most common autosomal recessive disorders in the world. Due to functional asplenia, a dysfunctional antibody response, antibiotic drug resistance and poor response to immunization, SCD patients have impaired immunity. A leading cause of hospitalization and death in SCD patients is the acute chest syndrome (ACS). This complication is especially manifested upon infection of SCD patients with Streptococcus pneumoniae (Spn)—a facultative anaerobic Gram-positive bacterium that causes lower respiratory tract infections. Spn has developed increased rates of antibiotics resistance and is particularly virulent in SCD patients. The primary defense against Spn is the generation of reactive oxygen species (ROS) during the oxidative burst of neutrophils and macrophages. Paradoxically, Spn itself produces high levels of the ROS hydrogen peroxide (H2O2) as a virulence strategy. Apart from H2O2, Spn also secretes another virulence factor, i.e., the pore-forming exotoxin pneumolysin (PLY), a potent mediator of lung injury in patients with pneumonia in general and particularly in those with SCD. PLY is released early on in infection either by autolysis or bacterial lysis following the treatment with antibiotics and has a broad range of biological activities. This review will discuss recent findings on the role of pneumococci in ACS pathogenesis and on strategies to counteract the devastating effects of its virulence factors on the lungs in SCD patients.
Collapse
|
9
|
Lucas R, Hadizamani Y, Gonzales J, Gorshkov B, Bodmer T, Berthiaume Y, Moehrlen U, Lode H, Huwer H, Hudel M, Mraheil MA, Toque HAF, Chakraborty T, Hamacher J. Impact of Bacterial Toxins in the Lungs. Toxins (Basel) 2020; 12:toxins12040223. [PMID: 32252376 PMCID: PMC7232160 DOI: 10.3390/toxins12040223] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/30/2020] [Accepted: 03/31/2020] [Indexed: 12/13/2022] Open
Abstract
Bacterial toxins play a key role in the pathogenesis of lung disease. Based on their structural and functional properties, they employ various strategies to modulate lung barrier function and to impair host defense in order to promote infection. Although in general, these toxins target common cellular signaling pathways and host compartments, toxin- and cell-specific effects have also been reported. Toxins can affect resident pulmonary cells involved in alveolar fluid clearance (AFC) and barrier function through impairing vectorial Na+ transport and through cytoskeletal collapse, as such, destroying cell-cell adhesions. The resulting loss of alveolar-capillary barrier integrity and fluid clearance capacity will induce capillary leak and foster edema formation, which will in turn impair gas exchange and endanger the survival of the host. Toxins modulate or neutralize protective host cell mechanisms of both the innate and adaptive immunity response during chronic infection. In particular, toxins can either recruit or kill central players of the lung's innate immune responses to pathogenic attacks, i.e., alveolar macrophages (AMs) and neutrophils. Pulmonary disorders resulting from these toxin actions include, e.g., acute lung injury (ALI), the acute respiratory syndrome (ARDS), and severe pneumonia. When acute infection converts to persistence, i.e., colonization and chronic infection, lung diseases, such as bronchitis, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF) can arise. The aim of this review is to discuss the impact of bacterial toxins in the lungs and the resulting outcomes for pathogenesis, their roles in promoting bacterial dissemination, and bacterial survival in disease progression.
Collapse
Affiliation(s)
- Rudolf Lucas
- Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
- Department of Medicine and Division of Pulmonary Critical Care Medicine, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
- Correspondence: (R.L.); (J.H.); Tel.: +41-31-300-35-00 (J.H.)
| | - Yalda Hadizamani
- Lungen-und Atmungsstiftung, Bern, 3012 Bern, Switzerland;
- Pneumology, Clinic for General Internal Medicine, Lindenhofspital Bern, 3012 Bern, Switzerland
| | - Joyce Gonzales
- Department of Medicine and Division of Pulmonary Critical Care Medicine, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
| | - Boris Gorshkov
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
| | - Thomas Bodmer
- Labormedizinisches Zentrum Dr. Risch, Waldeggstr. 37 CH-3097 Liebefeld, Switzerland;
| | - Yves Berthiaume
- Department of Medicine, Faculty of Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada;
| | - Ueli Moehrlen
- Pediatric Surgery, University Children’s Hospital, Zürich, Steinwiesstrasse 75, CH-8032 Zürch, Switzerland;
| | - Hartmut Lode
- Insitut für klinische Pharmakologie, Charité, Universitätsklinikum Berlin, Reichsstrasse 2, D-14052 Berlin, Germany;
| | - Hanno Huwer
- Department of Cardiothoracic Surgery, Voelklingen Heart Center, 66333 Voelklingen/Saar, Germany;
| | - Martina Hudel
- Justus-Liebig-University, Biomedical Research Centre Seltersberg, Schubertstr. 81, 35392 Giessen, Germany; (M.H.); (M.A.M.); (T.C.)
| | - Mobarak Abu Mraheil
- Justus-Liebig-University, Biomedical Research Centre Seltersberg, Schubertstr. 81, 35392 Giessen, Germany; (M.H.); (M.A.M.); (T.C.)
| | - Haroldo Alfredo Flores Toque
- Pharmacology and Toxicology, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA;
| | - Trinad Chakraborty
- Justus-Liebig-University, Biomedical Research Centre Seltersberg, Schubertstr. 81, 35392 Giessen, Germany; (M.H.); (M.A.M.); (T.C.)
| | - Jürg Hamacher
- Lungen-und Atmungsstiftung, Bern, 3012 Bern, Switzerland;
- Pneumology, Clinic for General Internal Medicine, Lindenhofspital Bern, 3012 Bern, Switzerland
- Medical Clinic V-Pneumology, Allergology, Intensive Care Medicine and Environmental Medicine, Faculty of Medicine, Saarland University, University Medical Centre of the Saarland, D-66421 Homburg, Germany
- Institute for Clinical & Experimental Surgery, Faculty of Medicine, Saarland University, D-66421 Homburg, Germany
- Correspondence: (R.L.); (J.H.); Tel.: +41-31-300-35-00 (J.H.)
| |
Collapse
|
10
|
Moyé S, Bormann T, Maus R, Sparwasser T, Sandrock I, Prinz I, Warnecke G, Welte T, Gauldie J, Kolb M, Maus UA. Regulatory T Cells Limit Pneumococcus-Induced Exacerbation of Lung Fibrosis in Mice. THE JOURNAL OF IMMUNOLOGY 2020; 204:2429-2438. [PMID: 32213566 DOI: 10.4049/jimmunol.1900980] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 03/02/2020] [Indexed: 12/28/2022]
Abstract
Patients with idiopathic pulmonary fibrosis (IPF) can experience life-threatening episodes of acute worsening of their disease, termed acute exacerbation of IPF, which may be caused by bacterial and/or viral infections. The potential for regulatory T cells (Tregs) to limit disease progression in bacterially triggered fibrosis exacerbation has not been explored so far. In the current study, we show that the number of Tregs was significantly increased in mice with established AdTGF-β1-induced lung fibrosis and further increased in mice with pneumococcal infection-induced lung fibrosis exacerbation. Diphtheria toxin-induced depletion of Tregs significantly worsened infection-induced fibrosis exacerbation as determined by increased lung collagen deposition, lung histology, and elevated pulmonary Th1/Th2 cytokine levels. Conversely, IL-2 complex-induced Treg expansion in wild-type mice with established lung fibrosis completely inhibited pneumococcal infection-induced fibrosis exacerbation as efficaciously as antibiotic treatment while preserving lung antibacterial immunity in mice. Collectively, these findings demonstrate the efficacy of Tregs as "silencers," suppressing infection-induced exacerbation of lung fibrosis in mice, and their expansion may offer a novel adjunctive treatment to limit acute exacerbations in patients with IPF.
Collapse
Affiliation(s)
- Steffi Moyé
- Division of Experimental Pneumology, Hannover Medical School, Hannover 30625, Germany
| | - Tina Bormann
- Division of Experimental Pneumology, Hannover Medical School, Hannover 30625, Germany
| | - Regina Maus
- Division of Experimental Pneumology, Hannover Medical School, Hannover 30625, Germany
| | - Tim Sparwasser
- Department of Medical Microbiology and Hygiene, University Medical Center Mainz, Mainz 55131, Germany
| | - Inga Sandrock
- Institute of Immunology, Hannover Medical School, Hannover 30625, Germany
| | - Immo Prinz
- Institute of Immunology, Hannover Medical School, Hannover 30625, Germany
| | - Gregor Warnecke
- Division of Cardiac, Thoracic, Transplantation, and Vascular Surgery, Hannover Medical School, Hannover 30625, Germany.,Partner Site BREATH, German Center for Lung Research, Hannover 30625, Germany
| | - Tobias Welte
- Partner Site BREATH, German Center for Lung Research, Hannover 30625, Germany.,Clinic for Pneumology, Hannover Medical School, Hannover 30625, Germany; and
| | | | | | - Ulrich A Maus
- Division of Experimental Pneumology, Hannover Medical School, Hannover 30625, Germany; .,Partner Site BREATH, German Center for Lung Research, Hannover 30625, Germany
| |
Collapse
|
11
|
Adams W, Bhowmick R, Bou Ghanem EN, Wade K, Shchepetov M, Weiser JN, McCormick BA, Tweten RK, Leong JM. Pneumolysin Induces 12-Lipoxygenase-Dependent Neutrophil Migration during Streptococcus pneumoniae Infection. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2020; 204:101-111. [PMID: 31776202 PMCID: PMC7195902 DOI: 10.4049/jimmunol.1800748] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 10/16/2019] [Indexed: 12/23/2022]
Abstract
Streptococcus pneumoniae is a major cause of pneumonia, wherein infection of respiratory mucosa drives a robust influx of neutrophils. We have previously shown that S. pneumoniae infection of the respiratory epithelium induces the production of the 12-lipoxygenase (12-LOX)-dependent lipid inflammatory mediator hepoxilin A3, which promotes recruitment of neutrophils into the airways, tissue damage, and lethal septicemia. Pneumolysin (PLY), a member of the cholesterol-dependent cytolysin (CDC) family, is a major S. pneumoniae virulence factor that generates ∼25-nm diameter pores in eukaryotic membranes and promotes acute inflammation, tissue damage, and bacteremia. We show that a PLY-deficient S. pneumoniae mutant was impaired in triggering human neutrophil transepithelial migration in vitro. Ectopic production of PLY endowed the nonpathogenic Bacillus subtilis with the ability to trigger neutrophil recruitment across human-cultured monolayers. Purified PLY, several other CDC family members, and the α-toxin of Clostridium septicum, which generates pores with cross-sectional areas nearly 300 times smaller than CDCs, reproduced this robust neutrophil transmigration. PLY non-pore-forming point mutants that are trapped at various stages of pore assembly did not recruit neutrophils. PLY triggered neutrophil recruitment in a 12-LOX-dependent manner in vitro. Instillation of wild-type PLY but not inactive derivatives into the lungs of mice induced robust 12-LOX-dependent neutrophil migration into the airways, although residual inflammation induced by PLY in 12-LOX-deficient mice indicates that 12-LOX-independent pathways also contribute to PLY-triggered pulmonary inflammation. These data indicate that PLY is an important factor in promoting hepoxilin A3-dependent neutrophil recruitment across pulmonary epithelium in a pore-dependent fashion.
Collapse
Affiliation(s)
- Walter Adams
- Department of Molecular Biology and Microbiology, Tufts University, Boston, MA 02111
- Department of Biological Sciences, San Jose State University, San Jose, CA 95192
| | - Rudra Bhowmick
- Department of Molecular Biology and Microbiology, Tufts University, Boston, MA 02111
| | - Elsa N Bou Ghanem
- Department of Molecular Biology and Microbiology, Tufts University, Boston, MA 02111
| | - Kristin Wade
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104
| | - Mikhail Shchepetov
- Department of Microbiology, University of Pennsylvania, Philadelphia, PA 19104
| | - Jeffrey N Weiser
- Department of Microbiology, New York University School of Medicine, New York, NY 10016; and
| | - Beth A McCormick
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01655
| | - Rodney K Tweten
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104
| | - John M Leong
- Department of Molecular Biology and Microbiology, Tufts University, Boston, MA 02111;
| |
Collapse
|
12
|
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.
Collapse
|
13
|
Bonniaud P, Fabre A, Frossard N, Guignabert C, Inman M, Kuebler WM, Maes T, Shi W, Stampfli M, Uhlig S, White E, Witzenrath M, Bellaye PS, Crestani B, Eickelberg O, Fehrenbach H, Guenther A, Jenkins G, Joos G, Magnan A, Maitre B, Maus UA, Reinhold P, Vernooy JHJ, Richeldi L, Kolb M. Optimising experimental research in respiratory diseases: an ERS statement. Eur Respir J 2018; 51:13993003.02133-2017. [PMID: 29773606 DOI: 10.1183/13993003.02133-2017] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 04/02/2018] [Indexed: 12/15/2022]
Abstract
Experimental models are critical for the understanding of lung health and disease and are indispensable for drug development. However, the pathogenetic and clinical relevance of the models is often unclear. Further, the use of animals in biomedical research is controversial from an ethical perspective.The objective of this task force was to issue a statement with research recommendations about lung disease models by facilitating in-depth discussions between respiratory scientists, and to provide an overview of the literature on the available models. Focus was put on their specific benefits and limitations. This will result in more efficient use of resources and greater reduction in the numbers of animals employed, thereby enhancing the ethical standards and translational capacity of experimental research.The task force statement addresses general issues of experimental research (ethics, species, sex, age, ex vivo and in vitro models, gene editing). The statement also includes research recommendations on modelling asthma, chronic obstructive pulmonary disease, pulmonary fibrosis, lung infections, acute lung injury and pulmonary hypertension.The task force stressed the importance of using multiple models to strengthen validity of results, the need to increase the availability of human tissues and the importance of standard operating procedures and data quality.
Collapse
Affiliation(s)
- Philippe Bonniaud
- Service de Pneumologie et Soins Intensifs Respiratoires, Centre Hospitalo-Universitaire de Bourgogne, Dijon, France.,Faculté de Médecine et Pharmacie, Université de Bourgogne-Franche Comté, Dijon, France.,INSERM U866, Dijon, France
| | - Aurélie Fabre
- Dept of Histopathology, St Vincent's University Hospital, UCD School of Medicine, University College Dublin, Dublin, Ireland
| | - Nelly Frossard
- Laboratoire d'Innovation Thérapeutique, Université de Strasbourg, Strasbourg, France.,CNRS UMR 7200, Faculté de Pharmacie, Illkirch, France.,Labex MEDALIS, Université de Strasbourg, Strasbourg, France
| | - Christophe Guignabert
- INSERM UMR_S 999, Le Plessis-Robinson, France.,Université Paris-Sud and Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - Mark Inman
- Dept of Medicine, Firestone Institute for Respiratory Health at St Joseph's Health Care MDCL 4011, McMaster University, Hamilton, ON, Canada
| | - Wolfgang M Kuebler
- Institute of Physiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Tania Maes
- Dept of Respiratory Medicine, Laboratory for Translational Research in Obstructive Pulmonary Diseases, Ghent University Hospital, Ghent, Belgium
| | - Wei Shi
- Developmental Biology and Regenerative Medicine Program, The Saban Research Institute of Children's Hospital Los Angeles, Los Angeles, CA, USA.,Dept of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Martin Stampfli
- Dept of Medicine, Firestone Institute for Respiratory Health at St Joseph's Health Care MDCL 4011, McMaster University, Hamilton, ON, Canada.,Dept of Pathology and Molecular Medicine, McMaster Immunology Research Centre, McMaster University
| | - Stefan Uhlig
- Institute of Pharmacology and Toxicology, RWTH Aachen University, Aachen, Germany
| | - Eric White
- Division of Pulmonary and Critical Care Medicine, Dept of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Martin Witzenrath
- Dept of Infectious Diseases and Respiratory Medicine And Division of Pulmonary Inflammation, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Pierre-Simon Bellaye
- Département de Médecine nucléaire, Plateforme d'imagerie préclinique, Centre George-François Leclerc (CGFL), Dijon, France
| | - Bruno Crestani
- Assistance Publique-Hôpitaux de Paris, Hôpital Bichat, DHU FIRE, Service de Pneumologie A, Paris, France.,INSERM UMR 1152, Paris, France.,Université Paris Diderot, Paris, France
| | - Oliver Eickelberg
- Division of Pulmonary Sciences and Critical Care Medicine, Dept of Medicine, University of Colorado, Aurora, CO, USA
| | - Heinz Fehrenbach
- Priority Area Asthma & Allergy, Research Center Borstel, Airway Research Center North (ARCN), German Center for Lung Research (DZL), Borstel, Germany.,Member of the Leibniz Research Alliance Health Technologies
| | - Andreas Guenther
- Justus-Liebig-University Giessen, Universitary Hospital Giessen, Agaplesion Lung Clinic Waldhof-Elgershausen, German Center for Lung Research, Giessen, Germany
| | - Gisli Jenkins
- Nottingham Biomedical Research Centre, Respiratory Research Unit, City Campus, University of Nottingham, Nottingham, UK
| | - Guy Joos
- Dept of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium
| | - Antoine Magnan
- Institut du thorax, CHU de Nantes, Université de Nantes, Nantes, France
| | - Bernard Maitre
- Hôpital H Mondor, AP-HP, Centre Hospitalier Intercommunal de Créteil, Service de Pneumologie et de Pathologie Professionnelle, DHU A-TVB, Université Paris Est - Créteil, Créteil, France
| | - Ulrich A Maus
- Hannover School of Medicine, Division of Experimental Pneumology, Hannover, Germany
| | - Petra Reinhold
- Institute of Molecular Pathogenesis at the 'Friedrich-Loeffler-Institut' (Federal Research Institute for Animal Health), Jena, Germany
| | - Juanita H J Vernooy
- Dept of Respiratory Medicine, Maastricht University Medical Center+ (MUMC+), AZ Maastricht, The Netherlands
| | - Luca Richeldi
- UOC Pneumologia, Università Cattolica del Sacro Cuore, Fondazione Policlinico Universitario "A. Gemelli", Rome, Italy
| | - Martin Kolb
- Dept of Medicine, Firestone Institute for Respiratory Health at St Joseph's Health Care MDCL 4011, McMaster University, Hamilton, ON, Canada
| |
Collapse
|
14
|
Singpiel A, Kramer J, Maus R, Stolper J, Bittersohl LF, Gauldie J, Kolb M, Welte T, Sparwasser T, Maus UA. Adenoviral vector-mediated GM-CSF gene transfer improves anti-mycobacterial immunity in mice - role of regulatory T cells. Immunobiology 2017; 223:331-341. [PMID: 29089144 DOI: 10.1016/j.imbio.2017.10.042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 10/19/2017] [Indexed: 01/23/2023]
Abstract
Granulocyte macrophage-colony stimulating factor (GM-CSF) is a hematopoietic growth factor involved in differentiation, survival and activation of myeloid and non-myeloid cells with important implications for lung antibacterial immunity. Here we examined the effect of pulmonary adenoviral vector-mediated delivery of GM-CSF (AdGM-CSF) on anti-mycobacterial immunity in M. bovis BCG infected mice. Exposure of M. bovis BCG infected mice to AdGM-CSF either applied on 6h, or 6h and 7days post-infection substantially increased alveolar recruitment of iNOS and IL-12 expressing macrophages, and significantly increased accumulation of IFNγpos T cells and particularly regulatory T cells (Tregs). This was accompanied by significantly reduced mycobacterial loads in the lungs of mice. Importantly, diphtheria toxin-induced depletion of Tregs did not influence mycobacterial loads, but accentuated immunopathology in AdGM-CSF-exposed mice infected with M. bovis BCG. Together, the data demonstrate that AdGM-CSF therapy improves lung protective immunity against M. bovis BCG infection in mice independent of co-recruited Tregs, which however critically contribute to limit lung immunopathology in BCG-infected mice. These data may be relevant to the development of immunomodulatory strategies to limit immunopathology-based lung injury in tuberculosis in humans.
Collapse
Affiliation(s)
| | | | - Regina Maus
- Department of Experimental Pneumology, Germany
| | | | | | - Jack Gauldie
- Department of Medicine, Pathology and Molecular Medicine, McMaster University, Hamilton, Canada
| | - Martin Kolb
- Department of Medicine, Pathology and Molecular Medicine, McMaster University, Hamilton, Canada
| | - Tobias Welte
- Clinic for Pneumology, Hannover Medical School, Germany; German Center for Infection Research, Hannover, Germany
| | - Tim Sparwasser
- Institute of Infection Immunology, Twincore, Centre for Experimental and Clinical Infection Research, Germany
| | - Ulrich A Maus
- Department of Experimental Pneumology, Germany; German Center for Infection Research, Hannover, Germany.
| |
Collapse
|
15
|
Rabes A, Suttorp N, Opitz B. Inflammasomes in Pneumococcal Infection: Innate Immune Sensing and Bacterial Evasion Strategies. Curr Top Microbiol Immunol 2017; 397:215-27. [PMID: 27460812 DOI: 10.1007/978-3-319-41171-2_11] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Streptococcus pneumoniae frequently colonizes the upper respiratory tract of healthy individuals, but also commonly causes severe invasive infections such as community-acquired pneumonia and meningitis. One of the key virulence factors of pneumococci is the pore-forming toxin pneumolysin which stimulates cell death and is involved in the evasion of some defense mechanisms. The immune system, however, employs different inflammasomes to sense pneumolysin-induced pore formation, cellular membrane damage, and/or subsequent leakage of bacterial nucleic acid into the host cell cytosol. Canonical inflammasomes are cytosolic multiprotein complexes consisting of a receptor molecule such as NLRP3 or AIM2, the adapter ASC, and caspase-1. NLRP3 and AIM2 inflammasomes mediate cell death and production of important IL-1 family cytokines to recruit leukocytes and defend against S. pneumoniae. Here, we review recent evidence that highlights inflammasomes as critical sensors of S. pneumoniae-induced cellular perturbations, summarize their role in pneumococcal infections, and discuss potential evasion strategies of some emerging pneumococcal strains.
Collapse
Affiliation(s)
- Anne Rabes
- Department of Internal Medicine/Infectious Diseases and Pulmonary Medicine, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Norbert Suttorp
- Department of Internal Medicine/Infectious Diseases and Pulmonary Medicine, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Bastian Opitz
- Department of Internal Medicine/Infectious Diseases and Pulmonary Medicine, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany.
| |
Collapse
|
16
|
NLRP3 protects alveolar barrier integrity by an inflammasome-independent increase of epithelial cell adherence. Sci Rep 2016; 6:30943. [PMID: 27476670 PMCID: PMC4967923 DOI: 10.1038/srep30943] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 07/11/2016] [Indexed: 12/17/2022] Open
Abstract
Bacterial pneumonia is a major cause of acute lung injury and acute respiratory distress syndrome, characterized by alveolar barrier disruption. NLRP3 is best known for its ability to form inflammasomes and to regulate IL-1β and IL-18 production in myeloid cells. Here we show that NLRP3 protects the integrity of the alveolar barrier in a mouse model of Streptococcus pneumoniae-induced pneumonia, and ex vivo upon treatment of isolated perfused and ventilated lungs with the purified bacterial toxin, pneumolysin. We reveal that the preserving effect of NLRP3 on the lung barrier is independent of inflammasomes, IL-1β and IL-18. NLRP3 improves the integrity of alveolar epithelial cell monolayers by enhancing cellular adherence. Collectively, our study uncovers a novel function of NLRP3 by demonstrating that it protects epithelial barrier function independently of inflammasomes.
Collapse
|
17
|
Walker MM, Novak L, Widener R, Grubbs JA, King J, Hale JY, Ochs MM, Myers LE, Briles DE, Deshane J. PcpA Promotes Higher Levels of Infection and Modulates Recruitment of Myeloid-Derived Suppressor Cells during Pneumococcal Pneumonia. THE JOURNAL OF IMMUNOLOGY 2016; 196:2239-48. [PMID: 26829988 DOI: 10.4049/jimmunol.1402518] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 12/30/2015] [Indexed: 12/16/2022]
Abstract
We used two different infection models to investigate the kinetics of the PcpA-dependent pneumococcal disease in mice. In a bacteremic pneumonia model, we observed a PcpA-dependent increase in bacterial burden in the lungs, blood, liver, bronchoalveolar lavage, and spleens of mice at 24 h postinfection. This PcpA-dependent effect on bacterial burden appeared earlier (within 12 h) in the focal pneumonia model, which lacks bacteremia or sepsis. Histological changes show that the ability of pneumococci to make PcpA was associated with unresolved inflammation in both models of infection. Using our bacteremic pneumonia model we further investigated the effects of PcpA on recruitment of innate immune regulatory cells. The presence of PcpA was associated with increased IL-6 levels, suppressed production of TRAIL, and reduced infiltration of polymorphonuclear cells. The ability of pneumococci to make PcpA negatively modulated both the infiltration and apoptosis of macrophages and the recruitment of myeloid-derived suppressor-like cells. The latter have been shown to facilitate the clearance and control of bacterial pneumonia. Taken together, the ability to make PcpA was strongly associated with increased bacterial burden, inflammation, and negative regulation of innate immune cell recruitment to the lung tissue during bacteremic pneumonia.
Collapse
Affiliation(s)
- Melissa M Walker
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Lea Novak
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Rebecca Widener
- Department of Pediatrics, University of South Carolina School of Medicine, Columbia, SC 29203
| | - James Aaron Grubbs
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Janice King
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Joanetha Y Hale
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Martina M Ochs
- Sanofi Pasteur, Non-Clinical Product Performance, 69280 Marcy L'Etoile, France
| | - Lisa E Myers
- Sanofi Pasteur, Non-Clinical Product Performance, 69280 Marcy L'Etoile, France
| | - David E Briles
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294; Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294; Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL 35294; and
| | - Jessy Deshane
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294; Division of Pulmonary, Allergy and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, AL 35294
| |
Collapse
|
18
|
|
19
|
Nogo-B protects mice against lipopolysaccharide-induced acute lung injury. Sci Rep 2015; 5:12061. [PMID: 26174362 PMCID: PMC4502524 DOI: 10.1038/srep12061] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 06/09/2015] [Indexed: 12/11/2022] Open
Abstract
Nogo-B, a member of the reticulon 4 protein family, plays a critical role in tissue repair and acute inflammation. Its role in acute lung injury (ALI) remains unclear. Here, we assessed the function of Nogo-B during tissue injury in a lipopolysaccharide (LPS)-induced ALI mouse model. We found that pulmonary Nogo-B was significantly repressed after LPS instillation in C57BL/6 mice. Over-expression of pulmonary Nogo-B using an adenovirus vector carrying the Nogo-B-RFP-3flag gene (Ad-Nogo-B) significantly prolonged the survival of mice challenged with a lethal dose of LPS. The Ad-Nogo-B-treated mice also had less severe lung injury, less alveolar protein exudation, and a higher number of macrophages but less neutrophil infiltration compared with Ad-RFP-treated mice. Interestingly, microarray analysis showed that the Ad-Nogo-B-treated mice had different gene expression profiles compared with the controls and the prominent expression of genes related to wound healing and the humoral immune response after LPS induction. Of the 49 differently expressed genes, we found that the expression of PTX3 was significantly up-regulated following Nogo-B over-expression as observed in lung tissues and RAW264.7 cells. In conclusion, Nogo-B plays a protective role against LPS-induced ALI, and this effect might be exerted through the modulation of alveolar macrophage recruitment and PTX3 production.
Collapse
|
20
|
Knippenberg S, Ueberberg B, Maus R, Bohling J, Ding N, Tort Tarres M, Hoymann HG, Jonigk D, Izykowski N, Paton JC, Ogunniyi AD, Lindig S, Bauer M, Welte T, Seeger W, Guenther A, Sisson TH, Gauldie J, Kolb M, Maus UA. Streptococcus pneumoniae triggers progression of pulmonary fibrosis through pneumolysin. Thorax 2015; 70:636-46. [PMID: 25964315 DOI: 10.1136/thoraxjnl-2014-206420] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 04/02/2015] [Indexed: 01/22/2023]
Abstract
RATIONALE Respiratory tract infections are common in patients suffering from pulmonary fibrosis. The interplay between bacterial infection and fibrosis is characterised poorly. OBJECTIVES To assess the effect of Gram-positive bacterial infection on fibrosis exacerbation in mice. METHODS Fibrosis progression in response to Streptococcus pneumoniae was examined in two different mouse models of pulmonary fibrosis. MEASUREMENTS AND MAIN RESULTS We demonstrate that wild-type mice exposed to adenoviral vector delivery of active transforming growth factor-β1 (TGFß1) or diphteria toxin (DT) treatment of transgenic mice expressing the DT receptor (DTR) under control of the surfactant protein C (SPC) promoter (SPC-DTR) to induce pulmonary fibrosis developed progressive fibrosis following infection with Spn, without exhibiting impaired lung protective immunity against Spn. Antibiotic treatment abolished infection-induced fibrosis progression. The cytotoxin pneumolysin (Ply) of Spn caused this phenomenon in a TLR4-independent manner, as Spn lacking Ply (SpnΔply) failed to trigger progressive fibrogenesis, whereas purified recombinant Ply did. Progressive fibrogenesis was also observed in AdTGFβ1-exposed Ply-challenged TLR4 KO mice. Increased apoptotic cell death of alveolar epithelial cells along with an attenuated intrapulmonary release of antifibrogenic prostaglandin E2 was found to underlie progressive fibrogenesis in Ply-challenged AdTGFβ1-exposed mice. Importantly, vaccination of mice with the non-cytotoxic Ply derivative B (PdB) substantially attenuated Ply-induced progression of lung fibrosis in AdTGFβ1-exposed mice. CONCLUSIONS Our data unravel a novel mechanism by which infection with Spn through Ply release induces progression of established lung fibrosis, which can be attenuated by protein-based vaccination of mice.
Collapse
Affiliation(s)
- Sarah Knippenberg
- Department of Experimental Pneumology, Hannover Medical School, Hannover, Germany
| | - Bianca Ueberberg
- Department of Experimental Pneumology, Hannover Medical School, Hannover, Germany
| | - Regina Maus
- Department of Experimental Pneumology, Hannover Medical School, Hannover, Germany
| | - Jennifer Bohling
- Department of Experimental Pneumology, Hannover Medical School, Hannover, Germany
| | - Nadine Ding
- Department of Experimental Pneumology, Hannover Medical School, Hannover, Germany
| | | | - Heinz-Gerd Hoymann
- Fraunhofer Institute for Toxicology and Experimental Medicine, Hannover, Germany
| | - Danny Jonigk
- Institute of Pathology, Hannover Medical School, Hannover, Germany
| | - Nicole Izykowski
- Institute of Pathology, Hannover Medical School, Hannover, Germany
| | - James C Paton
- Research Centre for Infectious Diseases, School of Molecular and Biomedical Science, University of Adelaide, Adelaide, Australia
| | - Abiodun D Ogunniyi
- Research Centre for Infectious Diseases, School of Molecular and Biomedical Science, University of Adelaide, Adelaide, Australia
| | - Sandro Lindig
- Center for Sepsis Control and Care, University Hospital Jena, Friedrich Schiller University, Jena, Germany
| | - Michael Bauer
- Center for Sepsis Control and Care, University Hospital Jena, Friedrich Schiller University, Jena, Germany
| | - Tobias Welte
- Clinic for Pneumology, Hannover Medical School, Hannover, Germany German Centre for Lung Research, partner site BREATH and UGMLC
| | - Werner Seeger
- German Centre for Lung Research, partner site BREATH and UGMLC Faculty of Medicine, Department of Internal Medicine, Universities of Giessen and Marburg Lung Center, Giessen, Germany
| | - Andreas Guenther
- German Centre for Lung Research, partner site BREATH and UGMLC Faculty of Medicine, Department of Internal Medicine, Universities of Giessen and Marburg Lung Center, Giessen, Germany
| | - Thomas H Sisson
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Hospital, Michigan, USA
| | - Jack Gauldie
- Department of Medicine, Pathology, and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Martin Kolb
- Department of Medicine, Pathology, and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Ulrich A Maus
- Department of Experimental Pneumology, Hannover Medical School, Hannover, Germany German Centre for Lung Research, partner site BREATH and UGMLC
| |
Collapse
|
21
|
Bong Y, Shin SG, Koh SH, Lim JH. Interleukin-1β Participates in the Development of Pneumococcal Acute Lung Injury and Death by Promoting Alveolar Microvascular Leakage. ACTA ACUST UNITED AC 2015. [DOI: 10.4167/jbv.2015.45.2.93] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Younghoon Bong
- College of Veterinary Medicine, Chonnam National University, Gwangju, Korea
| | - Seul Gi Shin
- Department of Microbiology, Ewha Womans University School of Medicine, Seoul, Korea
| | - Seo Hyun Koh
- Department of Microbiology, Ewha Womans University School of Medicine, Seoul, Korea
| | - Jae Hyang Lim
- Department of Microbiology, Ewha Womans University School of Medicine, Seoul, Korea
- Gonda Department of Cell and Molecular Biology, House Ear Institute, University of Southern California, Los Angeles, CA, USA
| |
Collapse
|
22
|
Cole J, Aberdein J, Jubrail J, Dockrell DH. The role of macrophages in the innate immune response to Streptococcus pneumoniae and Staphylococcus aureus: mechanisms and contrasts. Adv Microb Physiol 2014; 65:125-202. [PMID: 25476766 DOI: 10.1016/bs.ampbs.2014.08.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Macrophages are critical mediators of innate immune responses against bacteria. The Gram-positive bacteria Streptococcus pneumoniae and Staphylococcus aureus express a range of virulence factors, which challenge macrophages' immune competence. We review how macrophages respond to this challenge. Macrophages employ a range of strategies to phagocytose and kill each pathogen. When the macrophages capacity to clear bacteria is overwhelmed macrophages play important roles in orchestrating the inflammatory response through pattern recognition receptor-mediated responses. Macrophages also ensure the inflammatory response is tightly constrained, to avoid tissue damage, and play an important role in downregulating the inflammatory response once initial bacterial replication is controlled.
Collapse
Affiliation(s)
- Joby Cole
- Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom
| | - Jody Aberdein
- Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom
| | - Jamil Jubrail
- Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom
| | - David H Dockrell
- Department of Infection and Immunity, University of Sheffield Medical School and Sheffield Teaching Hospitals, Sheffield, United Kingdom.
| |
Collapse
|
23
|
Czikora I, Alli A, Bao HF, Kaftan D, Sridhar S, Apell HJ, Gorshkov B, White R, Zimmermann A, Wendel A, Pauly-Evers M, Hamacher J, Garcia-Gabay I, Fischer B, Verin A, Bagi Z, Pittet JF, Shabbir W, Lemmens-Gruber R, Chakraborty T, Lazrak A, Matthay MA, Eaton DC, Lucas R. A novel tumor necrosis factor-mediated mechanism of direct epithelial sodium channel activation. Am J Respir Crit Care Med 2014; 190:522-32. [PMID: 25029038 DOI: 10.1164/rccm.201405-0833oc] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
RATIONALE Alveolar liquid clearance is regulated by Na(+) uptake through the apically expressed epithelial sodium channel (ENaC) and basolaterally localized Na(+)-K(+)-ATPase in type II alveolar epithelial cells. Dysfunction of these Na(+) transporters during pulmonary inflammation can contribute to pulmonary edema. OBJECTIVES In this study, we sought to determine the precise mechanism by which the TIP peptide, mimicking the lectin-like domain of tumor necrosis factor (TNF), stimulates Na(+) uptake in a homologous cell system in the presence or absence of the bacterial toxin pneumolysin (PLY). METHODS We used a combined biochemical, electrophysiological, and molecular biological in vitro approach and assessed the physiological relevance of the lectin-like domain of TNF in alveolar liquid clearance in vivo by generating triple-mutant TNF knock-in mice that express a mutant TNF with deficient Na(+) uptake stimulatory activity. MEASUREMENTS AND MAIN RESULTS TIP peptide directly activates ENaC, but not the Na(+)-K(+)-ATPase, upon binding to the carboxy-terminal domain of the α subunit of the channel. In the presence of PLY, a mediator of pneumococcal-induced pulmonary edema, this binding stabilizes the ENaC-PIP2-MARCKS complex, which is necessary for the open probability conformation of the channel and preserves ENaC-α protein expression, by means of blunting the protein kinase C-α pathway. Triple-mutant TNF knock-in mice are more prone than wild-type mice to develop edema with low-dose intratracheal PLY, correlating with reduced pulmonary ENaC-α subunit expression. CONCLUSIONS These results demonstrate a novel TNF-mediated mechanism of direct ENaC activation and indicate a physiological role for the lectin-like domain of TNF in the resolution of alveolar edema during inflammation.
Collapse
|
24
|
Czikora I, Sridhar S, Gorshkov B, Alieva IB, Kasa A, Gonzales J, Potapenko O, Umapathy NS, Pillich H, Rick FG, Block NL, Verin AD, Chakraborty T, Matthay MA, Schally AV, Lucas R. Protective effect of Growth Hormone-Releasing Hormone agonist in bacterial toxin-induced pulmonary barrier dysfunction. Front Physiol 2014; 5:259. [PMID: 25076911 PMCID: PMC4097355 DOI: 10.3389/fphys.2014.00259] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Accepted: 06/19/2014] [Indexed: 01/17/2023] Open
Abstract
RATIONALE Antibiotic treatment of patients infected with G(-) or G(+) bacteria promotes release of the toxins lipopolysaccharide (LPS) and pneumolysin (PLY) in their lungs. Growth Hormone-releasing Hormone (GHRH) agonist JI-34 protects human lung microvascular endothelial cells (HL-MVEC), expressing splice variant 1 (SV-1) of the receptor, from PLY-induced barrier dysfunction. We investigated whether JI-34 also blunts LPS-induced hyperpermeability. Since GHRH receptor (GHRH-R) signaling can potentially stimulate both cAMP-dependent barrier-protective pathways as well as barrier-disruptive protein kinase C pathways, we studied their interaction in GHRH agonist-treated HL-MVEC, in the presence of PLY, by means of siRNA-mediated protein kinase A (PKA) depletion. METHODS Barrier function measurements were done in HL-MVEC monolayers using Electrical Cell substrate Impedance Sensing (ECIS) and VE-cadherin expression by Western blotting. Capillary leak was assessed by Evans Blue dye (EBD) incorporation. Cytokine generation in broncho-alveolar lavage fluid (BALF) was measured by multiplex analysis. PKA and PKC-α activity were assessed by Western blotting. RESULTS GHRH agonist JI-34 significantly blunts LPS-induced barrier dysfunction, at least in part by preserving VE-cadherin expression, while not affecting inflammation. In addition to activating PKA, GHRH agonist also increases PKC-α activity in PLY-treated HL-MVEC. Treatment with PLY significantly decreases resistance in control siRNA-treated HL-MVEC, but does so even more in PKA-depleted monolayers. Pretreatment with GHRH agonist blunts PLY-induced permeability in control siRNA-treated HL-MVEC, but fails to improve barrier function in PKA-depleted PLY-treated monolayers. CONCLUSIONS GHRH signaling in HL-MVEC protects from both LPS and PLY-mediated endothelial barrier dysfunction and concurrently induces a barrier-protective PKA-mediated and a barrier-disruptive PKC-α-induced pathway in the presence of PLY, the former of which dominates the latter.
Collapse
Affiliation(s)
- Istvan Czikora
- Department of Pharmacology and Toxicology, Vascular Biology Center, Georgia Regents University Augusta, GA, USA
| | - Supriya Sridhar
- Department of Pharmacology and Toxicology, Vascular Biology Center, Georgia Regents University Augusta, GA, USA
| | - Boris Gorshkov
- Department of Pharmacology and Toxicology, Vascular Biology Center, Georgia Regents University Augusta, GA, USA
| | - Irina B Alieva
- Department of Pharmacology and Toxicology, Vascular Biology Center, Georgia Regents University Augusta, GA, USA ; Department of Electron Microscopy, A.N. Belozorksy Institute, Moscow State University Moscow, Russia
| | - Anita Kasa
- Department of Pharmacology and Toxicology, Vascular Biology Center, Georgia Regents University Augusta, GA, USA
| | - Joyce Gonzales
- Department of Medicine, Division of Pulmonary Medicine, Medical College of Georgia, Georgia Regents University Augusta, GA, USA
| | - Olena Potapenko
- Department of Pharmacology and Toxicology, Vascular Biology Center, Georgia Regents University Augusta, GA, USA
| | - Nagavedi S Umapathy
- Department of Pharmacology and Toxicology, Vascular Biology Center, Georgia Regents University Augusta, GA, USA
| | - Helena Pillich
- Department of Medicine, Institute of Medical Microbiology, Justus-Liebig University Giessen Giessen, Germany
| | - Ferenc G Rick
- Endocrine, Polypeptide and Cancer Institute, Veterans Affairs Medical Center Miami, FL, USA ; Department of Urology, Herbert Wertheim College of Medicine, Florida International University Miami, FL, USA
| | - Norman L Block
- Endocrine, Polypeptide and Cancer Institute, Veterans Affairs Medical Center Miami, FL, USA ; Department of Pathology, Miller School of Medicine, University of Miami Miami, FL, USA ; Department of Medicine, Miller School of Medicine, University of Miami Miami, FL, USA ; Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami Miami, FL, USA
| | - Alexander D Verin
- Department of Pharmacology and Toxicology, Vascular Biology Center, Georgia Regents University Augusta, GA, USA
| | - Trinad Chakraborty
- Endocrine, Polypeptide and Cancer Institute, Veterans Affairs Medical Center Miami, FL, USA
| | - Michael A Matthay
- Department of Medicine and Anesthesia, Cardiovascular Research Institute, University of California San Francisco San Francisco, CA, USA
| | - Andrew V Schally
- Endocrine, Polypeptide and Cancer Institute, Veterans Affairs Medical Center Miami, FL, USA ; Department of Pathology, Miller School of Medicine, University of Miami Miami, FL, USA ; Department of Medicine, Miller School of Medicine, University of Miami Miami, FL, USA ; Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami Miami, FL, USA
| | - Rudolf Lucas
- Department of Pharmacology and Toxicology, Vascular Biology Center, Georgia Regents University Augusta, GA, USA ; Department of Medicine, Division of Pulmonary Medicine, Medical College of Georgia, Georgia Regents University Augusta, GA, USA ; Department of Pharmacology and Toxicology, Medical College of Georgia, Georgia Regents University Augusta, GA, USA
| |
Collapse
|
25
|
Type I interferon protects against pneumococcal invasive disease by inhibiting bacterial transmigration across the lung. PLoS Pathog 2013; 9:e1003727. [PMID: 24244159 PMCID: PMC3820719 DOI: 10.1371/journal.ppat.1003727] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Accepted: 09/10/2013] [Indexed: 11/19/2022] Open
Abstract
Streptococcus pneumoniae infection is a leading cause of bacterial pneumonia, sepsis and meningitis and is associated with high morbidity and mortality. Type I interferon (IFN-I), whose contribution to antiviral and intracellular bacterial immunity is well established, is also elicited during pneumococcal infection, yet its functional significance is not well defined. Here, we show that IFN-I plays an important role in the host defense against pneumococci by counteracting the transmigration of bacteria from the lung to the blood. Mice that lack the type I interferon receptor (Ifnar1−/−) or mice that were treated with a neutralizing antibody against the type I interferon receptor, exhibited enhanced development of bacteremia following intranasal pneumococcal infection, while maintaining comparable bacterial numbers in the lung. In turn, treatment of mice with IFNβ or IFN-I-inducing synthetic double stranded RNA (poly(I:C)), dramatically reduced the development of bacteremia following intranasal infection with S. pneumoniae. IFNβ treatment led to upregulation of tight junction proteins and downregulation of the pneumococcal uptake receptor, platelet activating factor receptor (PAF receptor). In accordance with these findings, IFN-I reduced pneumococcal cell invasion and transmigration across epithelial and endothelial layers, and Ifnar1−/− mice showed overall enhanced lung permeability. As such, our data identify IFN-I as an important component of the host immune defense that regulates two possible mechanisms involved in pneumococcal invasion, i.e. PAF receptor-mediated transcytosis and tight junction-dependent pericellular migration, ultimately limiting progression from a site-restricted lung infection to invasive, lethal disease. Streptococcus pneumoniae infection is a leading cause of bacterial pneumonia and invasive diseases such as sepsis and meningitis, which are associated with high morbidity and mortality. Here we identified type I Interferons (IFN-I) as critical mediators that prevent the progression of a local lung infection with S. pneumoniae to invasive disease. We found that mice lacking the receptor for IFN-I, or which received antibodies that interfere with receptor activation, showed increased development of bacteremia upon lung infection with S. pneumoniae. Treating mice, or cell lines, with IFN-I protected against bacterial migration across epithelial and endothelial cell barriers, correlating with increased expression of tight junction proteins, which enhance the lung's barrier function, and reduced surface expression levels of platelet activating factor receptor, a host receptor known to be hijacked by bacteria for migration across the lung/blood and blood/brain barriers. Together, our results identify IFN-I as an important component of the host immune defense against invasion from a gram-positive, extracellular bacterium, possibly reflecting a general mechanism for the regulation of epithelial and endothelial barrier function that is critical for protection from pathogen invasion.
Collapse
|
26
|
Lucas R, Czikora I, Sridhar S, Zemskov EA, Oseghale A, Circo S, Cederbaum SD, Chakraborty T, Fulton DJ, Caldwell RW, Romero MJ. Arginase 1: an unexpected mediator of pulmonary capillary barrier dysfunction in models of acute lung injury. Front Immunol 2013; 4:228. [PMID: 23966993 PMCID: PMC3736115 DOI: 10.3389/fimmu.2013.00228] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 07/19/2013] [Indexed: 12/31/2022] Open
Abstract
The integrity of epithelial and endothelial barriers in the lower airspaces of the lungs has to be tightly regulated, in order to prevent leakage and to assure efficient gas exchange between the alveoli and capillaries. Both G− and G+ bacterial toxins, such as lipopolysaccharide and pneumolysin, respectively, can be released in high concentrations within the pulmonary compartments upon antibiotic treatment of patients suffering from acute respiratory distress syndrome (ARDS) or severe pneumonia. These toxins are able to impair endothelial barrier function, either directly, or indirectly, by induction of pro-inflammatory mediators and neutrophil sequestration. Toxin-induced endothelial hyperpermeability can involve myosin light chain phosphorylation and/or microtubule rearrangement. Endothelial nitric oxide synthase (eNOS) was proposed to be a guardian of basal barrier function, since eNOS knock-out mice display an impaired expression of inter-endothelial junction proteins and as such an increased vascular permeability, as compared to wild type mice. The enzyme arginase, the activity of which can be regulated by the redox status of the cell, exists in two isoforms – arginase 1 (cytosolic) and arginase 2 (mitochondrial) – both of which can be expressed in lung microvascular endothelial cells. Upon activation, arginase competes with eNOS for the substrate l-arginine, as such impairing eNOS-dependent NO generation and promoting reactive oxygen species generation by the enzyme. This mini-review will discuss recent findings regarding the interaction between bacterial toxins and arginase during acute lung injury and will as such address the role of arginase in bacterial toxin-induced pulmonary endothelial barrier dysfunction.
Collapse
Affiliation(s)
- Rudolf Lucas
- Vascular Biology Center, Medical College of Georgia, Georgia Regents University , Augusta, GA , USA ; Department of Pharmacology and Toxicology, Medical College of Georgia, Georgia Regents University , Augusta, GA , USA ; Division of Pulmonary Medicine, Medical College of Georgia, Georgia Regents University , Augusta, GA , USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
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.
Collapse
|
28
|
Los FCO, Randis TM, Aroian RV, Ratner AJ. Role of pore-forming toxins in bacterial infectious diseases. Microbiol Mol Biol Rev 2013; 77:173-207. [PMID: 23699254 PMCID: PMC3668673 DOI: 10.1128/mmbr.00052-12] [Citation(s) in RCA: 298] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Pore-forming toxins (PFTs) are the most common bacterial cytotoxic proteins and are required for virulence in a large number of important pathogens, including Streptococcus pneumoniae, group A and B streptococci, Staphylococcus aureus, Escherichia coli, and Mycobacterium tuberculosis. PFTs generally disrupt host cell membranes, but they can have additional effects independent of pore formation. Substantial effort has been devoted to understanding the molecular mechanisms underlying the functions of certain model PFTs. Likewise, specific host pathways mediating survival and immune responses in the face of toxin-mediated cellular damage have been delineated. However, less is known about the overall functions of PFTs during infection in vivo. This review focuses on common themes in the area of PFT biology, with an emphasis on studies addressing the roles of PFTs in in vivo and ex vivo models of colonization or infection. Common functions of PFTs include disruption of epithelial barrier function and evasion of host immune responses, which contribute to bacterial growth and spreading. The widespread nature of PFTs make this group of toxins an attractive target for the development of new virulence-targeted therapies that may have broad activity against human pathogens.
Collapse
Affiliation(s)
| | - Tara M. Randis
- Department of Pediatrics, Columbia University, New York, New York, USA
| | - Raffi V. Aroian
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, USA
| | - Adam J. Ratner
- Department of Pediatrics, Columbia University, New York, New York, USA
| |
Collapse
|
29
|
Steinwede K, Henken S, Bohling J, Maus R, Ueberberg B, Brumshagen C, Brincks EL, Griffith TS, Welte T, Maus UA. TNF-related apoptosis-inducing ligand (TRAIL) exerts therapeutic efficacy for the treatment of pneumococcal pneumonia in mice. ACTA ACUST UNITED AC 2012; 209:1937-52. [PMID: 23071253 PMCID: PMC3478925 DOI: 10.1084/jem.20120983] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Apoptotic death of alveolar macrophages observed during lung infection with Streptococcus pneumoniae is thought to limit overwhelming lung inflammation in response to bacterial challenge. However, the underlying apoptotic death mechanism has not been defined. Here, we examined the role of the TNF superfamily member TNF-related apoptosis-inducing ligand (TRAIL) in S. pneumoniae-induced macrophage apoptosis, and investigated the potential benefit of TRAIL-based therapy during pneumococcal pneumonia in mice. Compared with WT mice, Trail(-/-) mice demonstrated significantly decreased lung bacterial clearance and survival in response to S. pneumoniae, which was accompanied by significantly reduced apoptosis and caspase 3 cleavage but rather increased necrosis in alveolar macrophages. In WT mice, neutrophils were identified as a major source of intraalveolar released TRAIL, and their depletion led to a shift from apoptosis toward necrosis as the dominant mechanism of alveolar macrophage cell death in pneumococcal pneumonia. Therapeutic application of TRAIL or agonistic anti-DR5 mAb (MD5-1) dramatically improved survival of S. pneumoniae-infected WT mice. Most importantly, neutropenic mice lacking neutrophil-derived TRAIL were protected from lethal pneumonia by MD5-1 therapy. We have identified a previously unrecognized mechanism by which neutrophil-derived TRAIL induces apoptosis of DR5-expressing macrophages, thus promoting early bacterial killing in pneumococcal pneumonia. TRAIL-based therapy in neutropenic hosts may represent a novel antibacterial treatment option.
Collapse
Affiliation(s)
- Kathrin Steinwede
- Department of Experimental Pneumology and 2 Clinic for Pneumology, Hannover School of Medicine, Hannover 30625, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
FMS-like tyrosine kinase 3 ligand treatment of mice aggravates acute lung injury in response to Streptococcus pneumoniae: role of pneumolysin. Infect Immun 2012; 80:4281-90. [PMID: 23006850 DOI: 10.1128/iai.00854-12] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
FMS-like tyrosine kinase-3 ligand (Flt3L) is a dendritic cell (DC) growth and differentiation factor with potential in antitumor therapies and antibacterial immunization strategies. However, the effect of systemic Flt3L treatment on lung-protective immunity against bacterial infection is incompletely defined. Here, we examined the impact of deficient (in Flt3L knockout [KO] mice), normal (in wild-type [WT] mice), or increased Flt3L availability (in WT mice pretreated with Flt3L for 3, 5, or 7 days) on lung DC subset profiles and lung-protective immunity against the major lung-tropic pathogen, Streptococcus pneumoniae. Although in Flt3L-deficient mice the numbers of DCs positive for CD11b (CD11b(pos) DCs) and for CD103 (CD103(pos) DCs) were diminished, lung permeability, a marker of injury, was unaltered in response to S. pneumoniae. In contrast, WT mice pretreated with Flt3L particularly responded with increased numbers of CD11b(pos) DCs and with less pronounced numbers of CD103(pos) DCs and impaired bacterial clearance and with increased lung permeability following S. pneumoniae challenge. Notably, infection of Flt3L-pretreated mice with S. pneumoniae lacking the pore-forming toxin, pneumolysin (PLY), resulted in substantially less lung CD11b(pos) DCs activation and reduced lung permeability. Collectively, this study establishes that Flt3L treatment enhances the accumulation of proinflammatory activated lung CD11b(pos) DCs which contribute to acute lung injury in response to PLY released by S. pneumoniae.
Collapse
|
31
|
Lucas R, Yang G, Gorshkov BA, Zemskov EA, Sridhar S, Umapathy NS, Jezierska-Drutel A, Alieva IB, Leustik M, Hossain H, Fischer B, Catravas JD, Verin AD, Pittet JF, Caldwell RB, Mitchell TJ, Cederbaum SD, Fulton DJ, Matthay MA, Caldwell RW, Romero MJ, Chakraborty T. Protein kinase C-α and arginase I mediate pneumolysin-induced pulmonary endothelial hyperpermeability. Am J Respir Cell Mol Biol 2012; 47:445-53. [PMID: 22582175 DOI: 10.1165/rcmb.2011-0332oc] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Antibiotics-induced release of the pore-forming virulence factor pneumolysin (PLY) in patients with pneumococcal pneumonia results in its presence days after lungs are sterile and is a major factor responsible for the induction of permeability edema. Here we sought to identify major mechanisms mediating PLY-induced endothelial dysfunction. We evaluated PLY-induced endothelial hyperpermeability in human lung microvascular endothelial cells (HL-MVECs) and human lung pulmonary artery endothelial cells in vitro and in mice instilled intratracheally with PLY. PLY increases permeability in endothelial monolayers by reducing stable and dynamic microtubule content and modulating VE-cadherin expression. These events, dependent upon an increased calcium influx, are preceded by protein kinase C (PKC)-α activation, perturbation of the RhoA/Rac1 balance, and an increase in myosin light chain phosphorylation. At later time points, PLY treatment increases the expression and activity of arginase in HL-MVECs. Arginase inhibition abrogates and suppresses PLY-induced endothelial barrier dysfunction by restoring NO generation. Consequently, a specific PKC-α inhibitor and the TNF-derived tonoplast intrinsic protein peptide, which blunts PLY-induced PKC-α activation, are able to prevent activation of arginase in HL-MVECs and to reduce PLY-induced endothelial hyperpermeability in mice. Arginase I (AI)(+/-)/arginase II (AII)(-/-) C57BL/6 mice, displaying a significantly reduced arginase I expression in the lungs, are significantly less sensitive to PLY-induced capillary leak than their wild-type or AI(+/+)/AII(-/-) counterparts, indicating an important role for arginase I in PLY-induced endothelial hyperpermeability. These results identify PKC-α and arginase I as potential upstream and downstream therapeutic targets in PLY-induced pulmonary endothelial dysfunction.
Collapse
Affiliation(s)
- Rudolf Lucas
- Vascular Biology Center and Dept. of Pharmacology and Toxicology, Georgia Health Sciences University, 1459 Laney-Walker Blvd., Augusta, GA 30912-2500, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Neutralizing antibodies elicited by a novel detoxified pneumolysin derivative, PlyD1, provide protection against both pneumococcal infection and lung injury. Infect Immun 2012; 80:2212-20. [PMID: 22473606 DOI: 10.1128/iai.06348-11] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Streptococcus pneumoniae pneumolysin (PLY) is a virulence factor that causes toxic effects contributing to pneumococcal pneumonia. To date, deriving a PLY candidate vaccine with the appropriate detoxification and immune profile has been challenging. A pneumolysin protein that is appropriately detoxified and that retains its immunogenicity is a desirable vaccine candidate. In this study, we assessed the protective efficacy of our novel PlyD1 detoxified PLY variant and investigated its underlying mechanism of protection. Results have shown that PlyD1 immunization protected mice against lethal intranasal (i.n.) challenge with pneumococci and lung injury mediated by PLY challenge. Protection was associated with PlyD1-specific IgG titers and in vitro neutralization titers. Pretreatment of PLY with PlyD1-specific rat polyclonal antiserum prior to i.n. delivery of toxin reduced PLY-mediated lung lesions, interleukin-6 (IL-6) production, and neutrophil infiltration into lungs, indicating that protection from lung lesions induced by PLY is antibody mediated. Preincubation of PLY with a neutralizing monoclonal PLY antibody also specifically reduced the cytotoxic effects of PLY after i.n. inoculation in comparison to nonneutralizing monoclonal antibodies. These results indicate that the induction of neutralizing antibodies against PLY can contribute to protection against bacterial pneumonia by preventing the development of PLY-induced lung lesions and inflammation. Our detoxified PlyD1 antigen elicits such PLY neutralizing antibodies, thus serving as a candidate vaccine antigen for the prevention of pneumococcal pneumonia.
Collapse
|
33
|
Steinwede K, Maus R, Bohling J, Voedisch S, Braun A, Ochs M, Schmiedl A, Länger F, Gauthier F, Roes J, Welte T, Bange FC, Niederweis M, Bühling F, Maus UA. Cathepsin G and neutrophil elastase contribute to lung-protective immunity against mycobacterial infections in mice. THE JOURNAL OF IMMUNOLOGY 2012; 188:4476-87. [PMID: 22461690 DOI: 10.4049/jimmunol.1103346] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The neutrophil serine proteases cathepsin G (CG) and neutrophil elastase (NE) are involved in immune-regulatory processes and exert antibacterial activity against various pathogens. To date, their role and their therapeutic potential in pulmonary host defense against mycobacterial infections are poorly defined. In this work, we studied the roles of CG and NE in the pulmonary resistance against Mycobacterium bovis bacillus Calmette-Guérin (BCG). CG-deficient mice and even more pronounced CG/NE-deficient mice showed significantly impaired pathogen elimination to infection with M. bovis BCG in comparison to wild-type mice. Moreover, granuloma formation was more pronounced in M. bovis BCG-infected CG/NE-deficient mice in comparison to CG-deficient and wild-type mice. A close examination of professional phagocyte subsets revealed that exclusively neutrophils shuttled CG and NE into the bronchoalveolar space of M. bovis BCG-infected mice. Accordingly, chimeric wild-type mice with a CG/NE-deficient hematopoietic system displayed significantly increased lung bacterial loads in response to M. bovis BCG infection. Therapeutically applied human CG/NE encapsulated in liposomes colocalized with mycobacteria in alveolar macrophages, as assessed by laser scanning and electron microscopy. Importantly, therapy with CG/NE-loaded liposomes significantly reduced mycobacterial loads in the lungs of mice. Together, neutrophil-derived CG and NE critically contribute to deceleration of pathogen replication during the early phase of antimycobacterial responses. In addition, to our knowledge, we show for the first time that liposomal encapsulated CG/NE exhibit therapeutic potential against pulmonary mycobacterial infections. These findings may be relevant for novel adjuvant approaches in the treatment of tuberculosis in humans.
Collapse
Affiliation(s)
- Kathrin Steinwede
- Department of Experimental Pneumology, Hannover Medical School, Hannover 30625, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Weber M, Lambeck S, Ding N, Henken S, Kohl M, Deigner HP, Enot DP, Igwe EI, Frappart L, Kiehntopf M, Claus RA, Kamradt T, Weih D, Vodovotz Y, Briles DE, Ogunniyi AD, Paton JC, Maus UA, Bauer M. Hepatic induction of cholesterol biosynthesis reflects a remote adaptive response to pneumococcal pneumonia. FASEB J 2012; 26:2424-36. [DOI: 10.1096/fj.11-191957] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Martina Weber
- Department of Anaesthesiology and Intensive Care TherapyJena University HospitalJenaGermany
| | - Sandro Lambeck
- Center for Sepsis Control and CareJena University HospitalJenaGermany
| | - Nadine Ding
- Department of Experimental PneumologyHannover School of MedicineHannoverGermany
| | - Stefanie Henken
- Department of Experimental PneumologyHannover School of MedicineHannoverGermany
| | - Matthias Kohl
- Department of Anaesthesiology and Intensive Care TherapyJena University HospitalJenaGermany
| | | | | | | | - Lucien Frappart
- Department of PathologyUniversity Claude Bernard Lyon I and Inserm U590LyonFrance
| | - Michael Kiehntopf
- Institute for Clinical Chemistry and Laboratory MedicineJena University HospitalJenaGermany
| | - Ralf A. Claus
- Department of Anaesthesiology and Intensive Care TherapyJena University HospitalJenaGermany
- Center for Sepsis Control and CareJena University HospitalJenaGermany
| | - Thomas Kamradt
- Institute of ImmunologyJena University HospitalJenaGermany
| | - Debra Weih
- Leibniz Institute for Age ResearchFritz‐Lipmann InstituteJenaGermany
| | - Yoram Vodovotz
- Department of SurgeryUniversity of PittsburghPittsburghPennsylvaniaUSA
- Center for Inflammation and Regenerative ModelingMcGowan Institute for Regenerative MedicinePittsburghPennsylvaniaUSA
| | - David E. Briles
- Department of MicrobiologyUniversity of Alabama at BirminghamAlabamaUSA
| | - Abiodun D. Ogunniyi
- Research Centre for Infectious DiseasesSchool of Molecular and Biomedical ScienceUniversity of AdelaideAdelaideAustralia
| | - James C. Paton
- Research Centre for Infectious DiseasesSchool of Molecular and Biomedical ScienceUniversity of AdelaideAdelaideAustralia
| | - Ulrich A. Maus
- Department of Experimental PneumologyHannover School of MedicineHannoverGermany
| | - Michael Bauer
- Department of Anaesthesiology and Intensive Care TherapyJena University HospitalJenaGermany
- Center for Sepsis Control and CareJena University HospitalJenaGermany
| |
Collapse
|
35
|
Koppe U, Suttorp N, Opitz B. Recognition of Streptococcus pneumoniae by the innate immune system. Cell Microbiol 2012; 14:460-6. [DOI: 10.1111/j.1462-5822.2011.01746.x] [Citation(s) in RCA: 129] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
36
|
Agonist of growth hormone-releasing hormone reduces pneumolysin-induced pulmonary permeability edema. Proc Natl Acad Sci U S A 2012; 109:2084-9. [PMID: 22308467 DOI: 10.1073/pnas.1121075109] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Aggressive treatment with antibiotics in patients infected with Streptococcus pneumoniae induces release of the bacterial virulence factor pneumolysin (PLY). Days after lungs are sterile, this pore-forming toxin can still induce pulmonary permeability edema in patients, characterized by alveolar/capillary barrier dysfunction and impaired alveolar liquid clearance (ALC). ALC is mainly regulated through Na(+) transport by the apically expressed epithelial sodium channel (ENaC) and the basolaterally expressed Na(+)/K(+)-ATPase in type II alveolar epithelial cells. Because no standard treatment is currently available to treat permeability edema, the search for novel therapeutic candidates is of high priority. We detected mRNA expression for the active receptor splice variant SV1 of the hypothalamic polypeptide growth hormone-releasing hormone (GHRH), as well as for GHRH itself, in human lung microvascular endothelial cells (HL-MVEC). Therefore, we have evaluated the effect of the GHRH agonist JI-34 on PLY-induced barrier and ALC dysfunction. JI-34 blunts PLY-mediated endothelial hyperpermeability in monolayers of HL-MVEC, in a cAMP-dependent manner, by means of reducing the phosphorylation of myosin light chain and vascular endothelial (VE)-cadherin. In human airway epithelial H441 cells, PLY significantly impairs Na(+) uptake, but JI-34 restores it to basal levels by means of increasing cAMP levels. Intratracheal instillation of PLY into C57BL6 mice causes pulmonary alveolar epithelial and endothelial hyperpermeability as well as edema formation, all of which are blunted by JI-34. These findings point toward a protective role of the GHRH signaling pathway in PLY-induced permeability edema.
Collapse
|
37
|
Hahn I, Klaus A, Janze AK, Steinwede K, Ding N, Bohling J, Brumshagen C, Serrano H, Gauthier F, Paton JC, Welte T, Maus UA. Cathepsin G and neutrophil elastase play critical and nonredundant roles in lung-protective immunity against Streptococcus pneumoniae in mice. Infect Immun 2011; 79:4893-901. [PMID: 21911460 PMCID: PMC3232647 DOI: 10.1128/iai.05593-11] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 09/02/2011] [Indexed: 11/20/2022] Open
Abstract
Neutrophil serine proteases cathepsin G (CG), neutrophil elastase (NE), and proteinase 3 (PR3) have recently been shown to contribute to killing of Streptococcus pneumoniae in vitro. However, their relevance in lung-protective immunity against different serotypes of S. pneumoniae in vivo has not been determined so far. Here, we examined the effect of CG and CG/NE deficiency on the lung host defense against S. pneumoniae in mice. Despite similar neutrophil recruitment, both CG knockout (KO) mice and CG/NE double-KO mice infected with focal pneumonia-inducing serotype 19 S. pneumoniae demonstrated a severely impaired bacterial clearance, which was accompanied by lack of CG and NE but not PR3 proteolytic activity in recruited neutrophils, as determined using fluorescence resonance energy transfer (FRET) substrates. Moreover, both CG and CG/NE KO mice but not wild-type mice responded with increased lung permeability to infection with S. pneumoniae, resulting in severe respiratory distress and progressive mortality. Both neutrophil depletion and ablation of hematopoietic CG/NE in bone marrow chimeras abolished intra-alveolar CG and NE immunoreactivity and led to bacterial outgrowth in the lungs of mice, thereby identifying recruited neutrophils as the primary cellular source of intra-alveolar CG and NE. This is the first study showing a contribution of neutrophil-derived neutral serine proteases CG and NE to lung-protective immunity against focal pneumonia-inducing serotype 19 S. pneumoniae in mice. These data may be important for the development of novel intervention strategies to improve lung-protective immune mechanisms in critically ill patients suffering from severe pneumococcal pneumonia.
Collapse
Affiliation(s)
- Ines Hahn
- Department of Experimental Pneumology
| | | | | | | | | | | | | | - Hélène Serrano
- INSERM U618, Proteases et Vectorisation Pulmonaires, Universite Francois Rabelais de Tours, Tours, France
| | - Francis Gauthier
- INSERM U618, Proteases et Vectorisation Pulmonaires, Universite Francois Rabelais de Tours, Tours, France
| | - James C. Paton
- Research Centre for Infectious Diseases, School of Molecular and Biomedical Science, University of Adelaide, Adelaide, Australia
| | - Tobias Welte
- Clinic for Pneumology, Hannover School of Medicine, Hannover, Germany
| | | |
Collapse
|
38
|
Steinwede K, Tempelhof O, Bolte K, Maus R, Bohling J, Ueberberg B, Länger F, Christman JW, Paton JC, Ask K, Maharaj S, Kolb M, Gauldie J, Welte T, Maus UA. Local delivery of GM-CSF protects mice from lethal pneumococcal pneumonia. THE JOURNAL OF IMMUNOLOGY 2011; 187:5346-56. [PMID: 22003204 DOI: 10.4049/jimmunol.1101413] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The growth factor GM-CSF has an important role in pulmonary surfactant metabolism and the regulation of antibacterial activities of lung sentinel cells. However, the potential of intra-alveolar GM-CSF to augment lung protective immunity against inhaled bacterial pathogens has not been defined in preclinical infection models. We hypothesized that transient overexpression of GM-CSF in the lungs of mice by adenoviral gene transfer (Ad-GM-CSF) would protect mice from subsequent lethal pneumococcal pneumonia. Our data show that intra-alveolar delivery of Ad-GM-CSF led to sustained increased pSTAT5 expression and PU.1 protein expression in alveolar macrophages during a 28-d observation period. Pulmonary Ad-GM-CSF delivery 2-4 wk prior to infection of mice with Streptococcus pneumoniae significantly reduced mortality rates relative to control vector-treated mice. This increased survival was accompanied by increased inducible NO synthase expression, antibacterial activity, and a significant reduction in caspase-3-dependent apoptosis and secondary necrosis of lung sentinel cells. Importantly, therapeutic treatment of mice with rGM-CSF improved lung protective immunity and accelerated bacterial clearance after pneumococcal challenge. We conclude that prophylactic delivery of GM-CSF triggers long-lasting immunostimulatory effects in the lung in vivo and rescues mice from lethal pneumococcal pneumonia by improving antibacterial immunity. These data support use of novel antibiotic-independent immunostimulatory therapies to protect patients against bacterial pneumonias.
Collapse
Affiliation(s)
- Kathrin Steinwede
- Department of Experimental Pneumology, Hannover Medical School, Hannover 30625, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Witzenrath M, Pache F, Lorenz D, Koppe U, Gutbier B, Tabeling C, Reppe K, Meixenberger K, Dorhoi A, Ma J, Holmes A, Trendelenburg G, Heimesaat MM, Bereswill S, van der Linden M, Tschopp J, Mitchell TJ, Suttorp N, Opitz B. The NLRP3 Inflammasome Is Differentially Activated by Pneumolysin Variants and Contributes to Host Defense in Pneumococcal Pneumonia. THE JOURNAL OF IMMUNOLOGY 2011; 187:434-40. [DOI: 10.4049/jimmunol.1003143] [Citation(s) in RCA: 195] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
40
|
Streptococcus pneumoniae DNA initiates type I interferon signaling in the respiratory tract. mBio 2011; 2:e00016-11. [PMID: 21586648 PMCID: PMC3101776 DOI: 10.1128/mbio.00016-11] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The mucosal epithelium is the initial target for respiratory pathogens of all types. While type I interferon (IFN) signaling is traditionally associated with antiviral immunity, we demonstrate that the extracellular bacterial pathogen Streptococcus pneumoniae activates the type I IFN cascade in airway epithelial and dendritic cells. This response is dependent upon the pore-forming toxin pneumolysin. Pneumococcal DNA activates IFN-β expression through a DAI/STING/TBK1/IRF3 cascade. Tlr4−/−, Myd88−/−, Trif−/−, and Nod2−/− mutant mice had no impairment of type I IFN signaling. Induction of type I IFN signaling contributes to the eradication of pneumococcal carriage, as IFN-α/β receptor null mice had significantly increased nasal colonization with S. pneumoniae compared with that of wild-type mice. These studies suggest that the type I IFN cascade is a central component of the mucosal response to airway bacterial pathogens and is responsive to bacterial pathogen-associated molecular patterns that are capable of accessing intracellular receptors. The bacterium Streptococcus pneumoniae is a leading cause of bacterial pneumonia, leading to upwards of one million deaths a year worldwide and significant economic burden. Although it is known that antibody is critical for efficient phagocytosis, it is not known how this pathogen is sensed by the mucosal epithelium. We demonstrate that this extracellular pathogen activates mucosal signaling typically activated by viral pathogens via the pneumolysin pore to activate intracellular receptors and the type I interferon (IFN) cascade. Mice lacking the receptor to type I IFNs have a reduced ability to clear S. pneumoniae, suggesting that the type I IFN cascade is central to the mucosal clearance of this important pathogen.
Collapse
|
41
|
Kadioglu A, De Filippo K, Bangert M, Fernandes VE, Richards L, Jones K, Andrew PW, Hogg N. The integrins Mac-1 and alpha4beta1 perform crucial roles in neutrophil and T cell recruitment to lungs during Streptococcus pneumoniae infection. THE JOURNAL OF IMMUNOLOGY 2011; 186:5907-15. [PMID: 21460207 DOI: 10.4049/jimmunol.1001533] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Neutrophils and T cells play an important role in host protection against pulmonary infection caused by Streptococcus pneumoniae. However, the role of the integrins in recruitment of these cells to infected lungs is not well understood. In this study we used the twin approaches of mAb blockade and gene-deficient mice to investigate the relative impact of specific integrins on cellular recruitment and bacterial loads following pneumococcal infection. We find that both Mac-1 (CD11b/CD18) and α(4)β(1) (CD49d/CD29) integrins, but surprisingly not LFA-1 (CD11a/CD18), contribute to two aspects of the response. In terms of recruitment from the circulation into lungs, neutrophils depend on Mac-1 and α(4)β(1), whereas the T cells are entirely dependent on α(4)β(1). Second, immunohistochemistry results indicate that adhesion also plays a role within infected lung tissue itself. There is widespread expression of ICAM-1 within lung tissue. Use of ICAM-1(-/-) mice revealed that neutrophils make use of this Mac-1 ligand, not for lung entry or for migration within lung tissue, but for combating the pneumococcal infection. In contrast to ICAM-1, there is restricted and constitutive expression of the α(4)β(1) ligand, VCAM-1, on the bronchioles, allowing direct access of the leukocytes to the airways via this integrin at an early stage of pneumococcal infection. Therefore, integrins Mac-1 and α(4)β(1) have a pivotal role in prevention of pneumococcal outgrowth during disease both in regulating neutrophil and T cell recruitment into infected lungs and by influencing their behavior within the lung tissue itself.
Collapse
Affiliation(s)
- Aras Kadioglu
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester LE1 9HN, United Kingdom.
| | | | | | | | | | | | | | | |
Collapse
|
42
|
Smith AM, McCullers JA, Adler FR. Mathematical model of a three-stage innate immune response to a pneumococcal lung infection. J Theor Biol 2011; 276:106-16. [PMID: 21300073 DOI: 10.1016/j.jtbi.2011.01.052] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 11/05/2010] [Accepted: 01/31/2011] [Indexed: 11/17/2022]
Abstract
Pneumococcal pneumonia is a leading cause of death and a major source of human morbidity. The initial immune response plays a central role in determining the course and outcome of pneumococcal disease. We combine bacterial titer measurements from mice infected with Streptococcus pneumoniae with mathematical modeling to investigate the coordination of immune responses and the effects of initial inoculum on outcome. To evaluate the contributions of individual components, we systematically build a mathematical model from three subsystems that describe the succession of defensive cells in the lung: resident alveolar macrophages, neutrophils and monocyte-derived macrophages. The alveolar macrophage response, which can be modeled by a single differential equation, can by itself rapidly clear small initial numbers of pneumococci. Extending the model to include the neutrophil response required additional equations for recruitment cytokines and host cell status and damage. With these dynamics, two outcomes can be predicted: bacterial clearance or sustained bacterial growth. Finally, a model including monocyte-derived macrophage recruitment by neutrophils suggests that sustained bacterial growth is possible even in their presence. Our model quantifies the contributions of cytotoxicity and immune-mediated damage in pneumococcal pathogenesis.
Collapse
Affiliation(s)
- Amber M Smith
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | | | | |
Collapse
|
43
|
Martin EL, Souza DG, Fagundes CT, Amaral FA, Assenzio B, Puntorieri V, Del Sorbo L, Fanelli V, Bosco M, Delsedime L, Pinho JF, Lemos VS, Souto FO, Alves-Filho JC, Cunha FQ, Slutsky AS, Ruckle T, Hirsch E, Teixeira MM, Ranieri VM. Phosphoinositide-3 Kinase γ Activity Contributes to Sepsis and Organ Damage by Altering Neutrophil Recruitment. Am J Respir Crit Care Med 2010; 182:762-73. [DOI: 10.1164/rccm.201001-0088oc] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
44
|
Importance of CXC chemokine receptor 2 in alveolar neutrophil and exudate macrophage recruitment in response to pneumococcal lung infection. Infect Immun 2010; 78:2620-30. [PMID: 20368349 DOI: 10.1128/iai.01169-09] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sustained neutrophilic infiltration is known to contribute to organ damage, such as acute lung injury. CXC chemokine receptor 2 (CXCR2) is the major receptor regulating inflammatory neutrophil recruitment in acute and chronic inflamed tissues. Whether or not the abundant neutrophil recruitment observed in severe pneumonia is essential for protective immunity against Streptococcus pneumoniae infections is incompletely defined. Here we show that CXCR2 deficiency severely perturbs the recruitment of both neutrophils and exudate macrophages associated with a massive bacterial outgrowth in distal airspaces after infection with S. pneumoniae, resulting in 100% mortality in knockout (KO) mice within 3 days. Moreover, irradiated wild-type mice reconstituted with increasing amounts of CXCR2 KO bone marrow (10, 25, 50, and 75% KO) have correspondingly decreased numbers of both neutrophils and exudate macrophages, which is associated with a stepwise increase in bacterial burden and a reciprocal stepwise decrease in survival in S. pneumoniae-induced pulmonary infection. Finally, application of the CXCR2 antagonist SB-225002 resulted in decreased alveolar neutrophil and exudate macrophage recruitment in mice along with increased lung bacterial loads after infection with S. pneumoniae. Together, these data show that CXC chemokine receptor 2 serves a previously unrecognized nonredundant role in the regulation of both neutrophil and exudate macrophage recruitment to the lung in response to S. pneumoniae infection. In addition, we demonstrate that a threshold level of 10 to 25% of reduced neutrophil recruitment is sufficient to cause increased mortality in mice infected with S. pneumoniae.
Collapse
|
45
|
Immunization with a combination of three pneumococcal proteins confers additive and broad protection against Streptococcus pneumoniae Infections in Mice. Infect Immun 2009; 78:1276-83. [PMID: 20038538 DOI: 10.1128/iai.00473-09] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pneumococcal polysaccharide-based vaccines are effective in preventing pneumococcus infection; however, some drawbacks preclude their widespread use in developing and undeveloped countries. Here, we evaluated the protective effects of ATP-dependent caseinolytic protease (ClpP), pneumolysin mutant (DeltaA146 Ply), putative lipoate-protein ligase (Lpl), or combinations thereof against pneumococcal infections in mice. Vaccinated mice were intraperitoneally and/or intranasally challenged with different pneumococcal strains. In intraperitoneal challenge models with pneumococcal strain D39 (serotype 2), the most striking protection was obtained with the combination of the three antigens. Similarly, with the intranasal challenge models, (i) additive clearance of bacteria in lungs was observed for the combination of the three antigens and (ii) a combination vaccine conferred complete protection against intranasal infections of three of the four most common pneumococcal strains (serotypes 14, 19F, and 23F) and 80% protection for pneumococcal strain 6B. Even so, immunity to this combination could confer protection against pneumococcal infection with a mixture of four serotypes. Our results showed that the combination vaccine was as effective as the currently used vaccines (PCV7 and PPV23). These results indicate that system immunization with the combination of pneumococcal antigens could provide an additive and broad protection against Streptococcus pneumoniae in pneumonia and sepsis infection models.
Collapse
|
46
|
Role of Toll-like receptors 2 and 4 in pulmonary inflammation and injury induced by pneumolysin in mice. PLoS One 2009; 4:e7993. [PMID: 19956717 PMCID: PMC2776357 DOI: 10.1371/journal.pone.0007993] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Accepted: 10/27/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Pneumolysin (PLN) is an intracellular toxin of Streptococcus pneumoniae that has been implicated as a major virulence factor in infections caused by this pathogen. Conserved bacterial motifs are recognized by the immune system by pattern recognition receptors among which the family of Toll-like receptors (TLRs) prominently features. The primary objective of the present study was to determine the role of TLR2 and TLR4 in lung inflammation induced by intrapulmonary delivery of PLN. METHODOLOGY/RESULTS First, we confirmed that purified PLN activates cells via TLR4 (not via TLR2) in vitro, using human embryonic kidney cells transfected with either TLR2 or TLR4. Intranasal administration of PLN induced an inflammatory response in the pulmonary compartment of mice in vivo, as reflected by influx of neutrophils, release of proinflammatory cytokines and chemokines, and a rise in total protein concentrations in bronchoalveolar lavage fluid. These PLN-induced responses were dependent in part, not only on TLR4, but also on TLR2, as indicated by studies using TLR deficient mice. CONCLUSION These data suggest that although purified PLN is recognized by TLR4 in vitro, PLN elicits lung inflammation in vivo by mechanisms that may involve multiple TLRs.
Collapse
|
47
|
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.
Collapse
Affiliation(s)
- Jeffrey N Weiser
- Department of Microbiology and Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA, 19104, USA.
| |
Collapse
|
48
|
Hinojosa E, Boyd AR, Orihuela CJ. Age-associated inflammation and toll-like receptor dysfunction prime the lungs for pneumococcal pneumonia. J Infect Dis 2009; 200:546-54. [PMID: 19586419 DOI: 10.1086/600870] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Aging is associated with increased inflammation and risk of community-acquired pneumonia. Streptococcus pneumoniae co-opts the nuclear factor kappa B (NFkB)-regulated proteins polymeric immunoglobulin receptor (pIgR) and platelet-activating factor receptor (PAFr) to attach and invade cells. We sought to determine whether aging and chronic inflammation were associated with increased pIgR and PAFr levels in the lungs and increased susceptibility to S. pneumoniae infection. METHODS Lung protein and messenger RNA levels were quantitated using Western blot and quantitative polymerase chain reaction. NFkB activation was measured by electrophoretic mobility shift assay. Cytokine levels were measured by cytometric bead analysis. To model chronic inflammation, mice were implanted with osmotic pumps that delivered tumor necrosis factor-alpha. RESULTS Aged mice and those infused with tumor necrosis factor-alpha had increased levels of pIgR and PAFr in their lungs and were more susceptible to S. pneumoniae infection. During pneumonia, aged mice had reduced levels of pIgR and PAFr and less NFkB activation, despite greater bacterial burden. We determined that aged mice had decreased amounts of lung Toll-like receptors 1, 2, and 4 and reduced capacity to respond to S. pneumoniae with proinflammatory cytokine production. CONCLUSIONS Aged mice and, potentially, elderly humans are more susceptible to pneumonia because of a priming effect of chronic inflammation and Toll-like receptor dysfunction.
Collapse
Affiliation(s)
- Ernesto Hinojosa
- Department of Microbiology and Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229-3900, USA
| | | | | |
Collapse
|
49
|
Phosphodiesterase 2 inhibition diminished acute lung injury in murine pneumococcal pneumonia. Crit Care Med 2009; 37:584-90. [PMID: 19114892 DOI: 10.1097/ccm.0b013e3181959814] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Severe pneumococcal pneumonia frequently causes respiratory failure. Both pathogen factors and an uncontrolled host response may contribute to acute lung injury by impairing microvascular barrier function. Phosphodiesterase 2 (PDE2) was examined as a potential target in pneumonia-induced lung microvascular hyperpermeability. DESIGN Controlled, in vitro, ex vivo, and in vivo laboratory study. SUBJECTS Female Balb/C and C57Bl/6 mice, 8-12 weeks old. INTERVENTIONS Human umbilical vein endothelial cells and isolated mouse lungs were challenged with the pneumococcal exotoxin pneumolysin in the presence or absence of the selective PDE2 inhibitors 9-(6-phenyl-2-oxohex-3-yl)-2-(3,4-dimethoxybenzyl)-purin-6one (PDP) or hydroxy-PDP. Transcellular electrical resistance or human serum albumin leakage in bronchoalveolar lavage fluid was determined, respectively. In addition, we induced pneumococcal pneumonia in mice and treated with hydroxy-PDP via continuous subcutaneous application by osmotic pumps. Human serum albumin leakage in bronchoalveolar lavage fluid was measured 48 hours after transnasal infection, and lung specimens were analyzed by TaqMan real-time polymerase chain reaction and Western blot for PDE2 gene and protein expression. MEASUREMENTS AND MAIN RESULTS In isolated perfused mouse lungs and in human umbilical vein endothelial cell monolayers, selective inhibition of PDE2 markedly decreased pneumolysin-induced hyperpermeability. Furthermore, in murine pneumococcal pneumonia, pulmonary PDE2-mRNA and -protein expression was significantly increased, and pneumonia-induced vascular permeability was distinctively reduced by PDE2 inhibition. CONCLUSIONS PDE2 inhibition diminished microvascular leakage in pneumococcal pneumonia, and pulmonary PDE2 upregulation may play a crucial role in this respect. Selective PDE2 inhibitors thus may offer a promising therapeutic approach in severe pneumococcal pneumonia.
Collapse
|
50
|
Winter C, Herbold W, Maus R, Länger F, Briles DE, Paton JC, Welte T, Maus UA. Important role for CC chemokine ligand 2-dependent lung mononuclear phagocyte recruitment to inhibit sepsis in mice infected with Streptococcus pneumoniae. THE JOURNAL OF IMMUNOLOGY 2009; 182:4931-7. [PMID: 19342672 DOI: 10.4049/jimmunol.0804096] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The monocyte chemoattractant CCL2 is of major importance in inflammatory monocyte recruitment to the lungs in response to bacterial infection. Streptococcus pneumoniae is the most prevalent pathogen in community-acquired pneumonia causing significant morbidity and mortality worldwide. In the current study, we examined the role of CCL2 in lung-protective immunity against two strains of S. pneumoniae exhibiting different virulence profiles. Both wild-type mice and CCL2 knockout (KO) mice became septic within 24 h of infection with serotype 3 S. pneumoniae and died of infection by day 4 after challenge. In contrast, wild-type mice challenged with serotype 19 S. pneumoniae did not become septic or succumb to pneumococcal pneumonia, whereas CCL2 KO mice showed an early bacterial outgrowth in their lungs and sepsis starting by day 2 after infection, finally resulting in approximately 50% decreased survival compared with wild-type mice. This phenotype was not due to impaired lung neutrophil recruitment in the KO mice, but was characterized by a significantly reduced recruitment of lung exudate macrophages and conventional lung dendritic cells, suggesting that these two phagocyte subsets critically regulate protection against septic disease progression in mice. In conclusion, we show here a differential role for CCL2-dependent lung exudate macrophage and conventional dendritic cell recruitment that critically contributes to lung protective immunity against S. pneumoniae.
Collapse
Affiliation(s)
- Christine Winter
- Department of Pulmonary Medicine, Laboratory for Experimental Lung Research Hannover School of Medicine, Hannover, Germany
| | | | | | | | | | | | | | | |
Collapse
|