1
|
Roles of Eicosanoids in Regulating Inflammation and Neutrophil Migration as an Innate Host Response to Bacterial Infections. Infect Immun 2021; 89:e0009521. [PMID: 34031130 DOI: 10.1128/iai.00095-21] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Eicosanoids are lipid-based signaling molecules that play a unique role in innate immune responses. The multiple types of eicosanoids, such as prostaglandins (PGs) and leukotrienes (LTs), allow the innate immune cells to respond rapidly to bacterial invaders. Bacterial pathogens alter cyclooxygenase (COX)-derived prostaglandins (PGs) in macrophages, such as PGE2 15d-PGJ2, and lipoxygenase (LOX)-derived leukotriene LTB4, which has chemotactic functions. The PG synthesis and secretion are regulated by substrate availability of arachidonic acid and by the COX-2 enzyme, and the expression of this protein is regulated at multiple levels, both transcriptionally and posttranscriptionally. Bacterial pathogens use virulence strategies such as type three secretion systems (T3SSs) to deliver virulence factors altering the expression of eicosanoid-specific biosynthetic enzymes, thereby modulating the host response to bacterial lipopolysaccharides (LPS). Recent advances have identified a novel role of eicosanoids in inflammasome activation during intracellular infection with bacterial pathogens. Specifically, PGE2 was found to enhance inflammasome activation, driving the formation of pore-induced intracellular traps (PITs), thus trapping bacteria from escaping the dying cell. Finally, eicosanoids and IL-1β released from macrophages are implicated in the efferocytosis of neighboring neutrophils. Neutrophils play an essential role in phagocytosing and degrading PITs and associated bacteria to restore homeostasis. This review focuses on the novel functions of host-derived eicosanoids in the host-pathogen interactions.
Collapse
|
2
|
Jurado-Escobar R, Doña I, Triano-Cornejo J, Perkins JR, Pérez-Sánchez N, Testera-Montes A, Labella M, Bartra J, Laguna JJ, Estravís M, Agúndez JAG, Torres MJ, Cornejo-García JA. Genetic Variants in Cytosolic Phospholipase A2 Associated With Nonsteroidal Anti-Inflammatory Drug-Induced Acute Urticaria/Angioedema. Front Pharmacol 2021; 12:667824. [PMID: 33995098 PMCID: PMC8120030 DOI: 10.3389/fphar.2021.667824] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Accepted: 04/15/2021] [Indexed: 12/14/2022] Open
Abstract
Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the main triggers of drug hypersensitivity reactions, probably due to their high consumption worldwide. The most frequent type of NSAID hypersensitivity is NSAID cross-hypersensitivity, in which patients react to NSAIDs from different chemical groups in the absence of a specific immunological response. The underlying mechanism of NSAID cross-hypersensitivity has been linked to cyclooxygenase (COX)-1 inhibition causing an imbalance in the arachidonic acid pathway. Despite NSAID-induced acute urticaria/angioedema (NIUA) being the most frequent clinical phenotype, most studies have focused on NSAID-exacerbated respiratory disease. As NSAID cross-hypersensitivity reactions are idiosyncratic, only appearing in some subjects, it is believed that individual susceptibility is under the influence of genetic factors. Although associations with polymorphisms in genes from the AA pathway have been described, no previous study has evaluated the potential role of cytosolic phospholipase A2 (cPLA2) variants. This enzyme catalyzes the initial hydrolysis of membrane phospholipids to release AA, which can be subsequently metabolized into eicosanoids. Here, we analyzed for the first time the overall genetic variation in the cPLA2 gene (PLA2G4A) in NIUA patients. For this purpose, a set of tagging single nucleotide polymorphisms (tagSNPs) in PLA2G4A were selected using data from Europeans subjects in the 1,000 Genomes Project, and genotyped with the iPlex Sequenom MassArray technology. Two independent populations, each comprising NIUA patients and NSAID-tolerant controls, were recruited in Spain, for the purposes of discovery and replication, comprising a total of 1,128 individuals. Fifty-eight tagSNPs were successfully genotyped in the discovery cohort, of which four were significantly associated with NIUA after Bonferroni correction (rs2049963, rs2064471, rs12088010, and rs12746200). These polymorphisms were then genotyped in the replication cohort: rs2049963 was associated with increased risk for NIUA after Bonferroni correction under the dominant and additive models, whereas rs12088010 and rs12746200 were protective under these two inheritance models. Our results suggest a role for PLA2G4A polymorphisms in NIUA. However, further studies are required to replicate our findings, elucidate the mechanistic role, and evaluate the participation of PLA2G4A variants in other phenotypes induced by NSAID cross-hypersensitivity.
Collapse
Affiliation(s)
- Raquel Jurado-Escobar
- Allergy Research Group, Instituto De Investigación Biomédica De Málaga-IBIMA, Malaga, Spain.,Departamento De Medicina, Universidad De Málaga, Malaga, Spain
| | - Inmaculada Doña
- Allergy Research Group, Instituto De Investigación Biomédica De Málaga-IBIMA, Malaga, Spain.,Allergy Unit, Hospital Regional Universitario De Málaga, Malaga, Spain.,ARADyAL Network, Instituto De Salud Carlos III, Madrid, Spain
| | - José Triano-Cornejo
- Allergy Research Group, Instituto De Investigación Biomédica De Málaga-IBIMA, Malaga, Spain
| | - James R Perkins
- Department of Molecular Biology and Biochemistry, University of Malaga, Malaga, Spain.,CIBER De Enfermedades Raras (CIBERER), ISCIII, Madrid, Spain.,The Biomedical Research Institute of Malaga (IBIMA), Malaga, Spain
| | | | | | - Marina Labella
- Allergy Unit, Hospital Regional Universitario De Málaga, Malaga, Spain
| | - Joan Bartra
- ARADyAL Network, Instituto De Salud Carlos III, Madrid, Spain.,Allergy Section, Pneumology Department, Hospital Clinic, Universitat De Barcelona, Barcelona, Spain
| | - José J Laguna
- ARADyAL Network, Instituto De Salud Carlos III, Madrid, Spain.,Allergy Unit, Allergo-Anaesthesia Unit, Hospital Central De La Cruz Roja, Faculty of Medicine, Alfonso X El Sabio University, Madrid, Spain
| | - Miguel Estravís
- ARADyAL Network, Instituto De Salud Carlos III, Madrid, Spain.,Instituto De Investigación Biomédica De Salamanca (IBSAL), Salamanca, Spain
| | - José A G Agúndez
- ARADyAL Network, Instituto De Salud Carlos III, Madrid, Spain.,Institute of Molecular Pathology Biomarkers, UEx, Cáceres, Spain
| | - María J Torres
- Allergy Research Group, Instituto De Investigación Biomédica De Málaga-IBIMA, Malaga, Spain.,Departamento De Medicina, Universidad De Málaga, Malaga, Spain.,Allergy Unit, Hospital Regional Universitario De Málaga, Malaga, Spain.,ARADyAL Network, Instituto De Salud Carlos III, Madrid, Spain.,Nanostructures for Diagnosing and Treatment of Allergic Diseases Laboratory, Andalusian Center for Nanomedicine and Biotechnology-BIONAND, Malaga, Spain
| | - José A Cornejo-García
- Allergy Research Group, Instituto De Investigación Biomédica De Málaga-IBIMA, Malaga, Spain.,ARADyAL Network, Instituto De Salud Carlos III, Madrid, Spain
| |
Collapse
|
3
|
Brash AR. Challenging the evidence for hepoxilin A 3 being a mediator of neutrophil epithelial transmigration. Am J Physiol Lung Cell Mol Physiol 2020; 319:L752-L753. [PMID: 33021845 DOI: 10.1152/ajplung.00349.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Alan R Brash
- Division of Clinical Pharmacology, Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee
| |
Collapse
|
4
|
Allen PE, Martinez JJ. Modulation of Host Lipid Pathways by Pathogenic Intracellular Bacteria. Pathogens 2020; 9:pathogens9080614. [PMID: 32731350 PMCID: PMC7460438 DOI: 10.3390/pathogens9080614] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 07/17/2020] [Accepted: 07/25/2020] [Indexed: 12/22/2022] Open
Abstract
Lipids are a broad group of molecules required for cell maintenance and homeostasis. Various intracellular pathogens have developed mechanisms of modulating and sequestering host lipid processes for a large array of functions for both bacterial and host cell survival. Among the host cell lipid functions that intracellular bacteria exploit for infection are the modulation of host plasma membrane microdomains (lipid rafts) required for efficient bacterial entry; the recruitment of specific lipids for membrane integrity of intracellular vacuoles; and the utilization of host lipid droplets for the regulation of immune responses and for energy production through fatty acid β-oxidation and oxidative phosphorylation. The majority of published studies on the utilization of these host lipid pathways during infection have focused on intracellular bacterial pathogens that reside within a vacuole during infection and, thus, have vastly different requirements for host lipid metabolites when compared to those intracellular pathogens that are released into the host cytosol upon infection. Here we summarize the mechanisms by which intracellular bacteria sequester host lipid species and compare the modulation of host lipid pathways and metabolites during host cell infection by intracellular pathogens residing in either a vacuole or within the cytosol of infected mammalian cells. This review will also highlight common and unique host pathways necessary for intracellular bacterial growth that could potentially be targeted for therapeutic intervention.
Collapse
|
5
|
Aspergillus fumigatus Cell Wall Promotes Apical Airway Epithelial Recruitment of Human Neutrophils. Infect Immun 2020; 88:IAI.00813-19. [PMID: 31767773 DOI: 10.1128/iai.00813-19] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 11/19/2019] [Indexed: 02/06/2023] Open
Abstract
Aspergillus fumigatus is a ubiquitous fungal pathogen capable of causing multiple pulmonary diseases, including invasive aspergillosis, chronic necrotizing aspergillosis, fungal colonization, and allergic bronchopulmonary aspergillosis. Intact mucociliary barrier function and early airway neutrophil responses are critical for clearing fungal conidia from the host airways prior to establishing disease. Following inhalation, Aspergillus conidia deposit in the small airways, where they are likely to make their initial host encounter with epithelial cells. Challenges in airway infection models have limited the ability to explore early steps in the interactions between A. fumigatus and the human airway epithelium. Here, we use inverted air-liquid interface cultures to demonstrate that the human airway epithelium responds to apical stimulation by A. fumigatus to promote the transepithelial migration of neutrophils from the basolateral membrane surface to the apical airway surface. Promoting epithelial transmigration with Aspergillus required prolonged exposure with live resting conidia. Swollen conidia did not expedite epithelial transmigration. Using A. fumigatus strains containing deletions of genes for cell wall components, we identified that deletion of the hydrophobic rodlet layer or dihydroxynaphthalene-melanin in the conidial cell wall amplified the epithelial transmigration of neutrophils, using primary human airway epithelium. Ultimately, we show that an as-yet-unidentified nonsecreted cell wall protein is required to promote the early epithelial transmigration of human neutrophils into the airspace in response to A. fumigatus Together, these data provide critical insight into the initial epithelial host response to Aspergillus.
Collapse
|
6
|
Stevens JS, Gray MC, Morisseau C, Criss AK. Endocervical and Neutrophil Lipoxygenases Coordinate Neutrophil Transepithelial Migration to Neisseria gonorrhoeae. J Infect Dis 2019; 218:1663-1674. [PMID: 29905822 DOI: 10.1093/infdis/jiy347] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 06/06/2018] [Indexed: 12/13/2022] Open
Abstract
Background Infection with Neisseria gonorrhoeae (GC) is characterized by robust neutrophil influx that is insufficient to clear the bacteria. Sustained neutrophilic inflammation contributes to serious clinical sequelae that particularly affect women, including pelvic inflammatory disease and infertility. Methods We established a 3-component system using GC, End1 polarized human endocervical cells, and primary human neutrophils to investigate neutrophil transepithelial migration following infection. Results Neutrophil migration across endocervical monolayers increased with the infectious dose and required GC-epithelial cell contact. Epithelial protein kinase C, cytosolic phospholipase A2, 12R-lipoxygenase (LOX), and eLOX3 hepoxilin synthase were required for neutrophil transmigration to GC, and migration was abrogated by blocking the MRP2 efflux pump and by adding recombinant soluble epoxide hydrolase. These results are all consistent with epithelial cell production of the neutrophil chemoattractant hepoxilin A3 (HXA3). Neutrophil transmigration was also accompanied by increasing apical concentrations of leukotriene B4 (LTB4). Neutrophil 5-lipoxygenase and active BLT1 receptor were required for apical LTB4 and neutrophil migration. Conclusions Our data support a model in which GC-endocervical cell contact infection stimulates HXA3 production, driving neutrophil migration that is amplified by neutrophil-derived LTB4. Therapeutic targeting of these pathways could limit inflammation and deleterious clinical sequelae in women with gonorrhea.
Collapse
Affiliation(s)
- Jacqueline S Stevens
- Department of Microbiology, University of Virginia, Charlottesville.,Department of Immunology, University of Virginia, Charlottesville.,Department of Cancer Biology, University of Virginia, Charlottesville
| | - Mary C Gray
- Department of Microbiology, University of Virginia, Charlottesville.,Department of Immunology, University of Virginia, Charlottesville.,Department of Cancer Biology, University of Virginia, Charlottesville
| | - Christophe Morisseau
- Department of Entomology and Nematology, UC Davis Comprehensive Cancer Research Center, University of California, Davis
| | - Alison K Criss
- Department of Microbiology, University of Virginia, Charlottesville.,Department of Immunology, University of Virginia, Charlottesville.,Department of Cancer Biology, University of Virginia, Charlottesville
| |
Collapse
|
7
|
Lipid Droplets: A Significant but Understudied Contributor of Host⁻Bacterial Interactions. Cells 2019; 8:cells8040354. [PMID: 30991653 PMCID: PMC6523240 DOI: 10.3390/cells8040354] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 04/05/2019] [Accepted: 04/12/2019] [Indexed: 12/13/2022] Open
Abstract
Lipid droplets (LDs) are cytosolic lipid storage organelles that are important for cellular lipid metabolism, energy homeostasis, cell signaling, and inflammation. Several bacterial, viral and protozoal pathogens exploit host LDs to promote infection, thus emphasizing the importance of LDs at the host–pathogen interface. In this review, we discuss the thus far reported relation between host LDs and bacterial pathogens including obligate and facultative intracellular bacteria, and extracellular bacteria. Although there is less evidence for a LD–extracellular bacterial interaction compared to interactions with intracellular bacteria, in this review, we attempt to compare the bacterial mechanisms that target LDs, the host signaling pathways involved and the utilization of LDs by these bacteria. Many intracellular bacteria employ unique mechanisms to target host LDs and potentially obtain nutrients and lipids for vacuolar biogenesis and/or immune evasion. However, extracellular bacteria utilize LDs to either promote host tissue damage or induce host death. We also identify several areas that require further investigation. Along with identifying LD interactions with bacteria besides the ones reported, the precise mechanisms of LD targeting and how LDs benefit pathogens should be explored for the bacteria discussed in the review. Elucidating LD–bacterial interactions promises critical insight into a novel host–pathogen interaction.
Collapse
|
8
|
Huang C, Niethammer P. Tissue Damage Signaling Is a Prerequisite for Protective Neutrophil Recruitment to Microbial Infection in Zebrafish. Immunity 2019; 48:1006-1013.e6. [PMID: 29768163 DOI: 10.1016/j.immuni.2018.04.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 04/04/2018] [Accepted: 04/17/2018] [Indexed: 12/28/2022]
Abstract
Tissue damage and infection are deemed likewise triggers of innate immune responses. But whereas neutrophil responses to microbes are generally protective, neutrophil recruitment into damaged tissues without infection is deleterious. Why neutrophils respond to tissue damage and not just to microbes is unknown. Is it a flaw of the innate immune system that persists because evolution did not select against it, or does it provide a selective advantage? Here we dissect the contribution of tissue damage signaling to antimicrobial immune responses in a live vertebrate. By intravital imaging of zebrafish larvae, a powerful model for innate immunity, we show that prevention of tissue damage signaling upon microbial ear infection abrogates leukocyte chemotaxis and reduces animal survival, at least in part, through suppression of cytosolic phospholipase A2 (cPla2), which integrates tissue damage- and microbe-derived cues. Thus, microbial cues are insufficient, and damage signaling is essential for antimicrobial neutrophil responses in zebrafish.
Collapse
Affiliation(s)
- Cong Huang
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; BCMB Allied Program, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA
| | - Philipp Niethammer
- Cell Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
| |
Collapse
|
9
|
Lee CW, Wu CH, Chiang YC, Chen YL, Chang KT, Chuang CC, Lee IT. Carbon monoxide releasing molecule-2 attenuates Pseudomonas aeruginosa-induced ROS-dependent ICAM-1 expression in human pulmonary alveolar epithelial cells. Redox Biol 2018; 18:93-103. [PMID: 30007888 PMCID: PMC6039312 DOI: 10.1016/j.redox.2018.07.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 06/30/2018] [Accepted: 07/02/2018] [Indexed: 12/15/2022] Open
Abstract
Pseudomonas aeruginosa (P. aeruginosa) infection in the lung is common in patients with cystic fibrosis (CF). Intercellular adhesion molecule-1 (ICAM-1) is known to play a key role in lung inflammation. Acute inflammation and its timely resolution are important to ensure bacterial clearance and limit tissue damage. Carbon monoxide (CO) has been shown to exert anti-inflammatory effects in various tissues and organ systems. Here, we explored the protective effects and mechanisms of carbon monoxide releasing molecule-2 (CORM-2) on P. aeruginosa-induced inflammatory responses in human pulmonary alveolar epithelial cells (HPAEpiCs). We showed that P. aeruginosa induced prostaglandin E2 (PGE2)/interleukin-6 (IL-6)/ICAM-1 expression and monocyte adherence to HPAEpiCs. Moreover, P. aeruginosa-induced inflammatory responses were inhibited by transfection with siRNA of Toll-like receptor 4 (TLR4), PKCα, p47phox, JNK2, p42, p50, or p65. P. aeruginosa also induced PKCα, JNK, ERK1/2, and NF-κB activation. We further demonstrated that P. aeruginosa increased intracellular ROS generation via NADPH oxidase activation. On the other hand, P. aeruginosa-induced inflammation was inhibited by pretreatment with CORM-2. Preincubation with CORM-2 had no effects on TLR4 mRNA levels in response to P. aeruginosa. However, CORM-2 inhibits P. aeruginosa-induced inflammation by decreasing intracellular ROS generation. P. aeruginosa-induced PKCα, JNK, ERK1/2, and NF-κB activation was inhibited by CORM-2. Finally, we showed that P. aeruginosa induced levels of the biomarkers of inflammation in respiratory diseases, which were inhibited by pretreatment with CORM-2. Taken together, these data suggest that CORM-2 inhibits P. aeruginosa-induced PGE2/IL-6/ICAM-1 expression and lung inflammatory responses by reducing the ROS generation and the inflammatory pathways. CORM-2 inhibits P. aeruginosa-induced PGE2/IL-6/ICAM-1 expression. CORM-2 reduced PKCα phosphorylation in response to P. aeruginosa. We provide molecular mechanisms for antibacterial effects of CORM-2.
Collapse
Affiliation(s)
- Chiang-Wen Lee
- Division of Basic Medical Sciences, Department of Nursing and Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chiayi, Taiwan, ROC; Research Center for Industry of Human Ecology and Research Center for Chinese Herbal Medicine, Chang Gung University of Science and Technology, Taoyuan, Taiwan, ROC; Department of Rehabilitation, Chang Gung Memorial Hospital, Chia-Yi, Taiwan, ROC
| | - Cheng-Hsun Wu
- School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan, ROC
| | - Yao-Chang Chiang
- Division of Basic Medical Sciences, Department of Nursing and Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chiayi, Taiwan, ROC; Center for Drug Abuse and Addiction, China Medical University Hospital, China Medical University, Taichung, Taiwan, ROC
| | - Yuh-Lien Chen
- Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan, ROC
| | - Kuo-Ting Chang
- Translational Medicine Center, Taoyuan General Hospital, Ministry of Healthy and Welfare, Taoyuan, Taiwan, ROC
| | - Chu-Chun Chuang
- Department of Physical Therapy, China Medical University, Taichung, Taiwan, ROC
| | - I-Ta Lee
- Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan, ROC; Department of Nursing, College of Nursing, Hungkuang University, Taichung, Taiwan, ROC.
| |
Collapse
|
10
|
Abstract
The body is exposed to foreign pathogens every day, but remarkably, most pathogens are effectively cleared by the innate immune system without the need to invoke the adaptive immune response. Key cellular components of the innate immune system include macrophages and neutrophils and the recruitment and function of these cells are tightly regulated by chemokines and cytokines in the tissue space. Innate immune responses are also known to regulate development of adaptive immune responses often via the secretion of various cytokines. In addition to these protein regulators, numerous lipid mediators can also influence innate and adaptive immune functions. In this review, we cover one particular lipid regulator, prostaglandin E2 (PGE2) and describe its synthesis and signaling and what is known about the ability of this lipid to regulate immunity and host defense against viral, fungal and bacterial pathogens.
Collapse
Affiliation(s)
| | - Bethany B Moore
- Pulmonary and Critical Care Medicine Division, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA; Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
11
|
Cytosolic Phospholipase A 2α Promotes Pulmonary Inflammation and Systemic Disease during Streptococcus pneumoniae Infection. Infect Immun 2017; 85:IAI.00280-17. [PMID: 28808157 DOI: 10.1128/iai.00280-17] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 08/02/2017] [Indexed: 02/07/2023] Open
Abstract
Pulmonary infection by Streptococcus pneumoniae is characterized by a robust alveolar infiltration of neutrophils (polymorphonuclear cells [PMNs]) that can promote systemic spread of the infection if not resolved. We previously showed that 12-lipoxygenase (12-LOX), which is required to generate the PMN chemoattractant hepoxilin A3 (HXA3) from arachidonic acid (AA), promotes acute pulmonary inflammation and systemic infection after lung challenge with S. pneumoniae As phospholipase A2 (PLA2) promotes the release of AA, we investigated the role of PLA2 in local and systemic disease during S. pneumoniae infection. The group IVA cytosolic isoform of PLA2 (cPLA2α) was activated upon S. pneumoniae infection of cultured lung epithelial cells and was critical for AA release from membrane phospholipids. Pharmacological inhibition of this enzyme blocked S. pneumoniae-induced PMN transepithelial migration in vitro Genetic ablation of the cPLA2 isoform cPLA2α dramatically reduced lung inflammation in mice upon high-dose pulmonary challenge with S. pneumoniae The cPLA2α-deficient mice also suffered no bacteremia and survived a pulmonary challenge that was lethal to wild-type mice. Our data suggest that cPLA2α plays a crucial role in eliciting pulmonary inflammation during pneumococcal infection and is required for lethal systemic infection following S. pneumoniae lung challenge.
Collapse
|
12
|
Yonker LM, Pazos MA, Lanter BB, Mou H, Chu KK, Eaton AD, Bonventre JV, Tearney GJ, Rajagopal J, Hurley BP. Neutrophil-Derived Cytosolic PLA2α Contributes to Bacterial-Induced Neutrophil Transepithelial Migration. THE JOURNAL OF IMMUNOLOGY 2017; 199:2873-2884. [PMID: 28887431 DOI: 10.4049/jimmunol.1700539] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 08/17/2017] [Indexed: 11/19/2022]
Abstract
Eicosanoids are a group of bioactive lipids that are shown to be important mediators of neutrophilic inflammation; selective targeting of their function confers therapeutic benefit in a number of diseases. Neutrophilic airway diseases, including cystic fibrosis, are characterized by excessive neutrophil infiltration into the airspace. Understanding the role of eicosanoids in this process may reveal novel therapeutic targets. The eicosanoid hepoxilin A3 is a pathogen-elicited epithelial-produced neutrophil chemoattractant that directs transepithelial migration in response to infection. Following hepoxilin A3-driven transepithelial migration, neutrophil chemotaxis is amplified through neutrophil production of a second eicosanoid, leukotriene B4 (LTB4). The rate-limiting step of eicosanoid generation is the liberation of arachidonic acid by phospholipase A2, and the cytosolic phospholipase A2 (cPLA2)α isoform has been specifically shown to direct LTB4 synthesis in certain contexts. Whether cPLA2α is directly responsible for neutrophil synthesis of LTB4 in the context of Pseudomonas aeruginosa-induced neutrophil transepithelial migration has not been explored. Human and mouse neutrophil-epithelial cocultures were used to evaluate the role of neutrophil-derived cPLA2α in infection-induced transepithelial signaling by pharmacological and genetic approaches. Primary human airway basal stem cell-derived epithelial cultures and micro-optical coherence tomography, a new imaging modality that captures two- and three-dimensional real-time dynamics of neutrophil transepithelial migration, were applied. Evidence from these studies suggests that cPLA2α expressed by neutrophils, but not epithelial cells, plays a significant role in infection-induced neutrophil transepithelial migration by mediating LTB4 synthesis during migration, which serves to amplify the magnitude of neutrophil recruitment in response to epithelial infection.
Collapse
Affiliation(s)
- Lael M Yonker
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital, Boston, MA 02114.,Department of Pediatrics, Harvard Medical School, Boston, MA 02115
| | - Michael A Pazos
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital, Boston, MA 02114.,Department of Pediatrics, Harvard Medical School, Boston, MA 02115
| | - Bernard B Lanter
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital, Boston, MA 02114.,Department of Pediatrics, Harvard Medical School, Boston, MA 02115
| | - Hongmei Mou
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital, Boston, MA 02114.,Department of Pediatrics, Harvard Medical School, Boston, MA 02115.,Center for Regenerative Medicine, Massachusetts General Hospital, Boston, MA 02114
| | - Kengyeh K Chu
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114.,Department of Pathology, Harvard Medical School, Boston, MA 02115
| | - Alexander D Eaton
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital, Boston, MA 02114
| | - Joseph V Bonventre
- Department of Medicine, Harvard Medical School, Boston, MA 02115.,Renal Division, Brigham and Women's Hospital, Boston, MA 02115; and.,Biomedical Engineering Division, Brigham and Women's Hospital, Boston, MA 02115
| | - Guillermo J Tearney
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114.,Department of Pathology, Harvard Medical School, Boston, MA 02115
| | - Jayaraj Rajagopal
- Center for Regenerative Medicine, Massachusetts General Hospital, Boston, MA 02114.,Department of Medicine, Harvard Medical School, Boston, MA 02115
| | - Bryan P Hurley
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital, Boston, MA 02114; .,Department of Pediatrics, Harvard Medical School, Boston, MA 02115
| |
Collapse
|
13
|
Pazos MA, Lanter BB, Yonker LM, Eaton AD, Pirzai W, Gronert K, Bonventre JV, Hurley BP. Pseudomonas aeruginosa ExoU augments neutrophil transepithelial migration. PLoS Pathog 2017; 13:e1006548. [PMID: 28771621 PMCID: PMC5557605 DOI: 10.1371/journal.ppat.1006548] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 08/15/2017] [Accepted: 07/22/2017] [Indexed: 12/21/2022] Open
Abstract
Excessive neutrophil infiltration of the lungs is a common contributor to immune-related pathology in many pulmonary disease states. In response to pathogenic infection, airway epithelial cells produce hepoxilin A3 (HXA3), initiating neutrophil transepithelial migration. Migrated neutrophils amplify this recruitment by producing a secondary gradient of leukotriene B4 (LTB4). We sought to determine whether this two-step eicosanoid chemoattractant mechanism could be exploited by the pathogen Pseudomonas aeruginosa. ExoU, a P. aeruginosa cytotoxin, exhibits phospholipase A2 (PLA2) activity in eukaryotic hosts, an enzyme critical for generation of certain eicosanoids. Using in vitro and in vivo models of neutrophil transepithelial migration, we evaluated the impact of ExoU expression on eicosanoid generation and function. We conclude that ExoU, by virtue of its PLA2 activity, augments and compensates for endogenous host neutrophil cPLA2α function, leading to enhanced transepithelial migration. This suggests that ExoU expression in P. aeruginosa can circumvent immune regulation at key signaling checkpoints in the neutrophil, resulting in exacerbated neutrophil recruitment. Pseudomonas aeruginosa is an opportunistic pathogen that causes acute pneumonia in immune compromised patients, and infects 70–80% of patients suffering from cystic fibrosis. Infections can result in excessive airway inflammation, which lead to immune-mediated lung damage, in particular through the action of recruited white blood cells known as neutrophils. Certain strains of P. aeruginosa produce the exotoxin ExoU, which has been associated with increased virulence. ExoU causes host cell lysis by hydrolyzing host membrane lipids through its phospholipase activity. However, host phospholipases play a key role in immune signaling by mediating the production of lipids known as eicosanoids. We investigated whether separate from its cytolytic activity, ExoU could modulate host immune responses through its phospholipase activity by hijacking eicosanoid production. Using in vitro and in vivo models of neutrophil recruitment, we find that ExoU producing strains of P. aeruginosa elicit higher levels of the eicosanoid chemoattractant leukotriene B4 from migrated neutrophils. This results in increased neutrophil transepithelial migration. This work reveals a new mechanism for how bacterial pathogens alter our immune function, and highlights a new potential therapeutic strategy for moderating Pseudomonas pathogenesis in patients with cystic fibrosis and acute pneumonia.
Collapse
Affiliation(s)
- Michael A. Pazos
- Mucosal Immunology & Biology Research Center, Massachusetts General Hospital for Children, Boston, Massachusetts, United States of America
- Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Bernard B. Lanter
- Mucosal Immunology & Biology Research Center, Massachusetts General Hospital for Children, Boston, Massachusetts, United States of America
- Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Lael M. Yonker
- Mucosal Immunology & Biology Research Center, Massachusetts General Hospital for Children, Boston, Massachusetts, United States of America
- Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Alex D. Eaton
- Mucosal Immunology & Biology Research Center, Massachusetts General Hospital for Children, Boston, Massachusetts, United States of America
| | - Waheed Pirzai
- Mucosal Immunology & Biology Research Center, Massachusetts General Hospital for Children, Boston, Massachusetts, United States of America
| | - Karsten Gronert
- Vision Science Program, School of Optometry, University of California at Berkeley, Berkeley, California, United States of America
| | - Joseph V. Bonventre
- Renal Division and Biomedical Engineering Division, Brigham and Women's Hospital, Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Bryan P. Hurley
- Mucosal Immunology & Biology Research Center, Massachusetts General Hospital for Children, Boston, Massachusetts, United States of America
- Pediatrics, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
| |
Collapse
|
14
|
Nitric oxide prevents a pathogen-permissive granulocytic inflammation during tuberculosis. Nat Microbiol 2017; 2:17072. [PMID: 28504669 PMCID: PMC5461879 DOI: 10.1038/nmicrobiol.2017.72] [Citation(s) in RCA: 168] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 04/03/2017] [Indexed: 12/22/2022]
Abstract
Nitric oxide (NO) contributes to protection from tuberculosis (TB). It is generally assumed that this protection is due to direct inhibition of Mycobacterium tuberculosis (Mtb) growth, which prevents subsequent pathological inflammation. In contrast, we report NO primarily protects mice by repressing an interleukin-1 and 12/15-lipoxygenase dependent neutrophil recruitment cascade that promotes bacterial replication. Using Mtb mutants as indicators of the pathogen's environment, we inferred that granulocytic inflammation generates a nutrient-replete niche that supports Mtb growth. Parallel clinical studies indicate that a similar inflammatory pathway promotes TB in patients. The human 12/15 lipoxygenase ortholog, ALOX12, is expressed in cavitary TB lesions, the abundance of its products correlate with the number of airway neutrophils and bacterial burden, and a genetic polymorphism that increases ALOX12 expression is associated with TB risk. These data suggest that Mtb exploits neutrophilic inflammation to preferentially replicate at sites of tissue damage that promote contagion.
Collapse
|
15
|
Breznan D, Das DD, O'Brien JS, MacKinnon-Roy C, Nimesh S, Vuong NQ, Bernatchez S, DeSilva N, Hill M, Kumarathasan P, Vincent R. Differential cytotoxic and inflammatory potency of amorphous silicon dioxide nanoparticles of similar size in multiple cell lines. Nanotoxicology 2017; 11:223-235. [PMID: 28142331 DOI: 10.1080/17435390.2017.1287313] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The likelihood of environmental and health impacts of silicon dioxide nanoparticles (SiNPs) has risen, due to their increased use in products and applications. The biological potency of a set of similarly-sized amorphous SiNPs was investigated in a variety of cells to examine the influence of physico-chemical and biological factors on their toxicity. Cellular LDH and ATP, BrdU incorporation, resazurin reduction and cytokine release were measured in human epithelial A549, human THP-1 and mouse J774A.1 macrophage cells exposed for 24 h to suspensions of 5-15, 10-20 and 12 nm SiNPs and reference particles. The SiNPs were characterized in dry state and in suspension to determine their physico-chemical properties. The dose-response data were simplified into particle potency estimates to facilitate the comparison of multiple endpoints of biological effects in cells. Mouse macrophages were the most sensitive to SiNP exposures. Cytotoxicity of the individual cell lines was correlated while the cytokine responses differed, supported by cell type-specific differences in inflammation-associated pathways. SiNP (12 nm), the most cytotoxic and inflammogenic nanoparticle had the highest surface acidity, dry-state agglomerate size, the lowest trace metal and organics content, the smallest surface area and agglomerate size in suspension. Particle surface acidity appeared to be the most significant determinant of the overall biological activity of this set of nanoparticles. Combined with the nanoparticle characterization, integration of the biological potency estimates enabled a comprehensive determination of the cellular reactivity of the SiNPs. The approach shows promise as a useful tool for first-tier screening of SiNP toxicity.
Collapse
Affiliation(s)
- Dalibor Breznan
- a Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture , Ottawa , Canada
| | - Dharani D Das
- a Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture , Ottawa , Canada
| | - Julie S O'Brien
- a Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture , Ottawa , Canada
| | - Christine MacKinnon-Roy
- a Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture , Ottawa , Canada
| | - Surendra Nimesh
- a Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture , Ottawa , Canada
| | - Ngoc Q Vuong
- a Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture , Ottawa , Canada
| | - Stéphane Bernatchez
- b New Substances Assessment and Control Bureau, Health Canada, Tunney's Pasture , Ottawa , Canada
| | - Nimal DeSilva
- c Department of Earth and Environmental Sciences , University of Ottawa , Ottawa , Canada
| | - Myriam Hill
- b New Substances Assessment and Control Bureau, Health Canada, Tunney's Pasture , Ottawa , Canada
| | - Prem Kumarathasan
- a Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture , Ottawa , Canada
| | - Renaud Vincent
- a Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture , Ottawa , Canada
| |
Collapse
|
16
|
Pace-Asciak CR. Pathophysiology of the hepoxilins. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:383-96. [DOI: 10.1016/j.bbalip.2014.09.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 09/06/2014] [Accepted: 09/10/2014] [Indexed: 10/24/2022]
|
17
|
Pazos MA, Pirzai W, Yonker LM, Morisseau C, Gronert K, Hurley BP. Distinct cellular sources of hepoxilin A3 and leukotriene B4 are used to coordinate bacterial-induced neutrophil transepithelial migration. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2015; 194:1304-15. [PMID: 25548217 PMCID: PMC4297725 DOI: 10.4049/jimmunol.1402489] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Neutrophilic infiltration is a leading contributor to pathology in a number of pulmonary disease states, including cystic fibrosis. Hepoxilin A3 (HXA3) is a chemotactic eicosanoid shown to mediate the transepithelial passage of neutrophils in response to infection in several model systems and at multiple mucosal surfaces. Another well-known eicosanoid mediating general neutrophil chemotaxis is leukotriene B4 (LTB4). We sought to distinguish the roles of each eicosanoid in the context of infection of lung epithelial monolayers by Pseudomonas aeruginosa. Using human and mouse in vitro transwell model systems, we used a combination of biosynthetic inhibitors, receptor antagonists, as well as mutant sources of neutrophils to assess the contribution of each chemoattractant in driving neutrophil transepithelial migration. We found that following chemotaxis to epithelial-derived HXA3 signals, neutrophil-derived LTB4 is required to amplify the magnitude of neutrophil migration. LTB4 signaling is not required for migration to HXA3 signals, but LTB4 generation by migrated neutrophils plays a significant role in augmenting the initial HXA3-mediated migration. We conclude that HXA3 and LTB4 serve independent roles to collectively coordinate an effective neutrophilic transepithelial migratory response.
Collapse
Affiliation(s)
- Michael A Pazos
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Charlestown, MA 02129; Department of Pediatrics, Harvard Medical School, Boston, MA 02115
| | - Waheed Pirzai
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Charlestown, MA 02129; Department of Pediatrics, Harvard Medical School, Boston, MA 02115
| | - Lael M Yonker
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Charlestown, MA 02129; Department of Pediatrics, Harvard Medical School, Boston, MA 02115
| | - Christophe Morisseau
- Department of Entomology and University of California Davis Comprehensive Cancer Center, University of California, Davis, CA 95616; and
| | - Karsten Gronert
- Vision Science Program, School of Optometry, University of California at Berkeley, Berkeley, CA 94720
| | - Bryan P Hurley
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Charlestown, MA 02129; Department of Pediatrics, Harvard Medical School, Boston, MA 02115;
| |
Collapse
|
18
|
Guillemot L, Medina M, Pernet E, Leduc D, Chignard M, Touqui L, Wu Y. Cytosolic phospholipase A2α enhances mouse mortality induced by Pseudomonas aeruginosa pulmonary infection via interleukin 6. Biochimie 2014; 107 Pt A:95-104. [PMID: 25201511 DOI: 10.1016/j.biochi.2014.08.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 08/29/2014] [Indexed: 12/19/2022]
Abstract
Pseudomonas aeruginosa pulmonary infection is a leading cause of death in numerous diseases such as cystic fibrosis (CF). The host cytosolic phospholipase A2α (cPLA2α) releases lipid mediators that play an important role in the pathogenesis of diseases, but its role in lung injury induced by P. aeruginosa infection is still obscure. Using an animal model of P. aeruginosa lung infection, we showed that the CHA strain of P. aeruginosa was more potent than the PAK strain in inducing mouse mortality and lung injury, and that both mouse mortality and lung injury were reduced in cPLA2α(-/-) mice as compared to cPLA2α(+/+) mice. This was accompanied by decreased levels of IL6 but not other inflammatory cytokines (IL1β, KC and TNFα) in the bronchoalveolar lavage fluids (BALFs) of cPLA2α(-/-) mice. Given that CFTR(-/-) mice exhibit increased cPLA2α activation in the lung, the role of cPLA2α was further examined in this lung infection model. Compared to littermates, P. aeruginosa infection caused increased mortality in CFTR(-/-) mice with high IL6 levels in BALFs, which was attenuated by pharmacological inhibition of cPLA2α. In addition, compared to IL6(-/-) mice, an enhanced mortality was also observed in P. aeruginosa infected IL6(+/+) mice. Since alveolar macrophages (AMs) are the primary inflammatory cytokine source in the lung, murine AMs cell line (MH-S) were used to investigate the signalling pathways involved in this process. Incubation of MH-S cells with P. aeruginosa induced IL6 production, which was mediated by MAPKs ERK/p38 and was abolished by cPLA2α inhibitors. Furthermore, among cPLA2 downstream signalling pathways, only 15-lipoxygenase (15-LOX) and cyclooxygenase-2 (COX-2) were proven to participate in this P. aeruginosa-induced IL6 expression. Based on all these observations, we conclude that cPLA2α enhances P. aeruginosa-induced animal lethality in part via IL6 induction and that MAPKs ERK/p38, 15-LOX and COX-2 signalling pathways were involved in this process.
Collapse
Affiliation(s)
- Laurent Guillemot
- Unit of Innate Defence & Inflammation, Institut Pasteur, 25 rue Dr Roux, 75015 Paris, France; INSERM U874, 25 rue Dr Roux, 75015 Paris, France
| | - Mathieu Medina
- Unit of Innate Defence & Inflammation, Institut Pasteur, 25 rue Dr Roux, 75015 Paris, France; INSERM U874, 25 rue Dr Roux, 75015 Paris, France
| | - Erwan Pernet
- Unit of Innate Defence & Inflammation, Institut Pasteur, 25 rue Dr Roux, 75015 Paris, France; INSERM U874, 25 rue Dr Roux, 75015 Paris, France
| | - Dominique Leduc
- Unit of Innate Defence & Inflammation, Institut Pasteur, 25 rue Dr Roux, 75015 Paris, France; INSERM U874, 25 rue Dr Roux, 75015 Paris, France
| | - Michel Chignard
- Unit of Innate Defence & Inflammation, Institut Pasteur, 25 rue Dr Roux, 75015 Paris, France; INSERM U874, 25 rue Dr Roux, 75015 Paris, France
| | - Lhousseine Touqui
- Unit of Innate Defence & Inflammation, Institut Pasteur, 25 rue Dr Roux, 75015 Paris, France; INSERM U874, 25 rue Dr Roux, 75015 Paris, France
| | - Yongzheng Wu
- Unit of Innate Defence & Inflammation, Institut Pasteur, 25 rue Dr Roux, 75015 Paris, France; INSERM U874, 25 rue Dr Roux, 75015 Paris, France.
| |
Collapse
|
19
|
Junkins RD, Carrigan SO, Wu Z, Stadnyk AW, Cowley E, Issekutz T, Berman J, Lin TJ. Mast Cells Protect against Pseudomonas aeruginosa–Induced Lung Injury. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 184:2310-21. [DOI: 10.1016/j.ajpath.2014.05.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 04/07/2014] [Accepted: 05/12/2014] [Indexed: 01/09/2023]
|
20
|
Kusek ME, Pazos MA, Pirzai W, Hurley BP. In vitro coculture assay to assess pathogen induced neutrophil trans-epithelial migration. J Vis Exp 2014:e50823. [PMID: 24430378 DOI: 10.3791/50823] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Mucosal surfaces serve as protective barriers against pathogenic organisms. Innate immune responses are activated upon sensing pathogen leading to the infiltration of tissues with migrating inflammatory cells, primarily neutrophils. This process has the potential to be destructive to tissues if excessive or held in an unresolved state. Cocultured in vitro models can be utilized to study the unique molecular mechanisms involved in pathogen induced neutrophil trans-epithelial migration. This type of model provides versatility in experimental design with opportunity for controlled manipulation of the pathogen, epithelial barrier, or neutrophil. Pathogenic infection of the apical surface of polarized epithelial monolayers grown on permeable transwell filters instigates physiologically relevant basolateral to apical trans-epithelial migration of neutrophils applied to the basolateral surface. The in vitro model described herein demonstrates the multiple steps necessary for demonstrating neutrophil migration across a polarized lung epithelial monolayer that has been infected with pathogenic P. aeruginosa (PAO1). Seeding and culturing of permeable transwells with human derived lung epithelial cells is described, along with isolation of neutrophils from whole human blood and culturing of PAO1 and nonpathogenic K12 E. coli (MC1000). The emigrational process and quantitative analysis of successfully migrated neutrophils that have been mobilized in response to pathogenic infection is shown with representative data, including positive and negative controls. This in vitro model system can be manipulated and applied to other mucosal surfaces. Inflammatory responses that involve excessive neutrophil infiltration can be destructive to host tissues and can occur in the absence of pathogenic infections. A better understanding of the molecular mechanisms that promote neutrophil trans-epithelial migration through experimental manipulation of the in vitro coculture assay system described herein has significant potential to identify novel therapeutic targets for a range of mucosal infectious as well as inflammatory diseases.
Collapse
Affiliation(s)
- Mark E Kusek
- Department of Pediatrics, Harvard Medical School
| | | | | | | |
Collapse
|
21
|
Kubala SA, Patil SU, Shreffler WG, Hurley BP. Pathogen induced chemo-attractant hepoxilin A3 drives neutrophils, but not eosinophils across epithelial barriers. Prostaglandins Other Lipid Mediat 2013; 108:1-8. [PMID: 24315875 DOI: 10.1016/j.prostaglandins.2013.11.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 11/08/2013] [Accepted: 11/21/2013] [Indexed: 12/19/2022]
Abstract
Pathogen induced migration of neutrophils across mucosal epithelial barriers requires epithelial production of the chemotactic lipid mediator, hepoxilin A3 (HXA3). HXA3 is an eicosanoid derived from arachidonic acid. Although eosinophils are also capable of penetrating mucosal surfaces, eosinophilic infiltration occurs mainly during allergic processes whereas neutrophils dominate mucosal infection. Both neutrophils and eosinophils can respond to chemotactic gradients of certain eicosanoids, however, it is not known whether eosinophils respond to pathogen induced lipid mediators such as HXA3. In this study, neutrophils and eosinophils were isolated from human blood and placed on the basolateral side of polarized epithelial monolayers grown on permeable Transwell filters and challenged by various chemotactic gradients of distinct lipid mediators. We observed that both cell populations migrated across epithelial monolayers in response to a leukotriene B4 (LTB4) gradient, whereas only eosinophils migrated toward a prostaglandin D2 (PGD2) gradient. Interestingly, while pathogen induced neutrophil trans-epithelial migration was substantial, pathogen induced eosinophil trans-epithelial migration was not observed. Further, gradients of chemotactic lipids derived from pathogen infected epithelial cells known to be enriched for HXA3 as well as purified HXA3 drove significant numbers of neutrophils across epithelial barriers, whereas eosinophils failed to respond to these gradients. These data suggest that although the eicosanoid HXA3 serves as an important neutrophil chemo-attractant at mucosal surfaces during pathogenic infection, HXA3 does not appear to exhibit chemotactic activity toward eosinophils.
Collapse
Affiliation(s)
- S A Kubala
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, United States; Center for Immunology and Inflammatory Diseases and the Food Allergy Center, Massachusetts General Hospital, Charlestown, MA 02129, United States
| | - S U Patil
- Center for Immunology and Inflammatory Diseases and the Food Allergy Center, Massachusetts General Hospital, Charlestown, MA 02129, United States
| | - W G Shreffler
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, United States; Center for Immunology and Inflammatory Diseases and the Food Allergy Center, Massachusetts General Hospital, Charlestown, MA 02129, United States
| | - B P Hurley
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, United States; Mucosal Immunology & Biology Research Center, Massachusetts General Hospital, Charlestown, MA 02129, United States.
| |
Collapse
|
22
|
Pace-Asciak CR, Li X, Reynaud D, Qiao N, Demin P, Abdelhaleem M. Alterations in eicosanoid levels during U937 bcl-xL tumour growth suppression and recovery in NU/NU mice in vivo—Involvement of phospholipase A2. Prostaglandins Other Lipid Mediat 2013; 107:43-7. [DOI: 10.1016/j.prostaglandins.2013.03.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 02/13/2013] [Accepted: 03/14/2013] [Indexed: 11/15/2022]
|
23
|
Herold S, Gabrielli NM, Vadász I. Novel concepts of acute lung injury and alveolar-capillary barrier dysfunction. Am J Physiol Lung Cell Mol Physiol 2013; 305:L665-81. [PMID: 24039257 DOI: 10.1152/ajplung.00232.2013] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In this review we summarize recent major advances in our understanding on the molecular mechanisms, mediators, and biomarkers of acute lung injury (ALI) and alveolar-capillary barrier dysfunction, highlighting the role of immune cells, inflammatory and noninflammatory signaling events, mechanical noxae, and the affected cellular and molecular entities and functions. Furthermore, we address novel aspects of resolution and repair of ALI, as well as putative candidates for treatment of ALI, including pharmacological and cellular therapeutic means.
Collapse
Affiliation(s)
- Susanne Herold
- Dept. of Internal Medicine, Justus Liebig Univ., Universities of Giessen and Marburg Lung Center, Klinikstrasse 33, 35392 Giessen, Germany.
| | | | | |
Collapse
|
24
|
Agard M, Asakrah S, Morici LA. PGE(2) suppression of innate immunity during mucosal bacterial infection. Front Cell Infect Microbiol 2013; 3:45. [PMID: 23971009 PMCID: PMC3748320 DOI: 10.3389/fcimb.2013.00045] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 07/30/2013] [Indexed: 12/28/2022] Open
Abstract
Prostaglandin E2 (PGE2) is an important lipid mediator in inflammatory and immune responses during acute and chronic infections. Upon stimulation by various proinflammatory stimuli such as lipopolysaccharide (LPS), interleukin (IL)-1β, and tumor necrosis factor (TNF)-α, PGE2 synthesis is upregulated by the expression of cyclooxygenases. Biologically active PGE2 is then able to signal through four primary receptors to elicit a response. PGE2 is a critical molecule that regulates the activation, maturation, migration, and cytokine secretion of several immune cells, particularly those involved in innate immunity such as macrophages, neutrophils, natural killer cells, and dendritic cells. Both Gram-negative and Gram-positive bacteria can induce PGE2 synthesis to regulate immune responses during bacterial pathogenesis. This review will focus on PGE2 in innate immunity and how bacterial pathogens influence PGE2 production during enteric and pulmonary infections. The conserved ability of many bacterial pathogens to promote PGE2 responses during infection suggests a common signaling mechanism to deter protective pro-inflammatory immune responses. Inhibition of PGE2 production and signaling during infection may represent a therapeutic alternative to treat bacterial infections. Further study of the immunosuppressive effects of PGE2 on innate immunity will lead to a better understanding of potential therapeutic targets within the PGE2 pathway.
Collapse
Affiliation(s)
- Mallory Agard
- Department of Microbiology and Immunology, Tulane University School of Medicine New Orleans, LA 70119, USA
| | | | | |
Collapse
|
25
|
Jabr S, Gartner S, Milne GL, Roca-Ferrer J, Casas J, Moreno A, Gelpí E, Picado C. Quantification of major urinary metabolites of PGE2 and PGD2 in cystic fibrosis: correlation with disease severity. Prostaglandins Leukot Essent Fatty Acids 2013; 89:121-6. [PMID: 23791427 DOI: 10.1016/j.plefa.2013.06.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Revised: 06/02/2013] [Accepted: 06/03/2013] [Indexed: 12/17/2022]
Abstract
Cystic fibrosis transmembrane conductance (CFTR) alterations are involved in the overproduction of prostaglandins (PG) in CF in vitro. We assessed the relationship between PGE-M and PGD-M urinary metabolites of PGE2 and PGD2 and CF severity. Twenty-four controls and 35 CF patients were recruited. PGE-M and PGD-M levels were measured by liquid chromatography/mass spectrometry and results were expressed as median and 25th-75th interquartile of ng/mg creatinine (Cr). PGE-M (15.63; 9.07-43.35ng/mg Cr) and PGD-M (2.16; 1.43-3.53ng/mg Cr) concentrations were higher in CF than in controls: PGE-M, (6.63; 4.35-8.60ng/mg Cr); PGD-M (1.23; 0.96-1.54ng/mg Cr). There was no correlation between metabolite levels and spirometric values. Patients with pancreatic insufficiency (n=29) had higher PGE-M levels (19.09; 9.36-52.69ng/mg Cr) than those with conserved function (n=6) (9.61; 5.78-14.34ng/mg Cr). PGE-M levels were associated with genotype severity: mild (7.14; 5.76-8.76, n=8), moderate (16.67; 13.67-28.62ng/mg Cr, n=5) and severe (22.82; 10.67-84.13ng/mg Cr). Our study confirms the key role of CFTR in the regulation of the cyclooxygenase pathway of arachidonic acid metabolism found in in vitro studies.
Collapse
Affiliation(s)
- Suha Jabr
- Servei de Pneumologia, Hospital Cinic, Institut d'Investigacions Biomèdiques August PI i Sunyer (IDIBAPS), CIBERES, Universitat de Barcelona, 08036 Barcelona, Spain
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Szabady RL, McCormick BA. Control of neutrophil inflammation at mucosal surfaces by secreted epithelial products. Front Immunol 2013; 4:220. [PMID: 23914188 PMCID: PMC3728559 DOI: 10.3389/fimmu.2013.00220] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 07/15/2013] [Indexed: 12/30/2022] Open
Abstract
The human intestine is a large and delicately balanced organ, responsible for efficiently absorbing nutrients and selectively eliminating disease-causing pathogens. The gut architecture consists of a single layer of epithelial cells that forms a barrier against the food antigens and resident microbiota within the lumen. This barrier is augmented by a thick layer of mucus on the luminal side and an underlying lamina propria containing a resident population of immune cells. Attempted breaches of the intestinal barrier by pathogenic bacteria result in the rapid induction of a coordinated innate immune response that includes release of antimicrobial peptides, activation of pattern recognition receptors, and recruitment of various immune cells. In recent years, the role of epithelial cells in initiating this immune response has been increasingly appreciated. In particular, epithelial cells are responsible for the release of a variety of factors that attract neutrophils, the body's trained bacterial killers. In this review we will highlight recent research that details a new understanding of how epithelial cells directionally secrete specific compounds at distinct stages of the inflammatory response in order to coordinate the immune response to intestinal microbes. In addition to their importance during the response to infection, evidence suggests that dysregulation of these pathways may contribute to pathologic inflammation during inflammatory bowel disease. Therefore, a continued understanding of the mechanisms by which epithelial cells control neutrophil migration into the intestine will have tremendous benefits in both the understanding of biological processes and the identification of potential therapeutic targets.
Collapse
Affiliation(s)
- Rose L Szabady
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School , Worcester, MA , USA
| | | |
Collapse
|
27
|
Tamang DL, Pirzai W, Priebe GP, Traficante DC, Pier GB, Falck JR, Morisseau C, Hammock BD, McCormick BA, Gronert K, Hurley BP. Hepoxilin A(3) facilitates neutrophilic breach of lipoxygenase-expressing airway epithelial barriers. THE JOURNAL OF IMMUNOLOGY 2012; 189:4960-9. [PMID: 23045615 DOI: 10.4049/jimmunol.1201922] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A feature shared by many inflammatory lung diseases is excessive neutrophilic infiltration. Neutrophil homing to airspaces involve multiple factors produced by several distinct cell types. Hepoxilin A(3) is a neutrophil chemoattractant produced by pathogen-infected epithelial cells that is hypothesized to facilitate neutrophil breach of mucosal barriers. Using a Transwell model of lung epithelial barriers infected with Pseudomonas aeruginosa, we explored the role of hepoxilin A(3) in neutrophil transepithelial migration. Pharmacological inhibitors of the enzymatic pathways necessary to generate hepoxilin A(3), including phospholipase A(2) and 12-lipoxygenase, potently interfere with P. aeruginosa-induced neutrophil transepithelial migration. Both transformed and primary human lung epithelial cells infected with P. aeruginosa generate hepoxilin A(3) precursor arachidonic acid. All four known lipoxygenase enzymes capable of synthesizing hepoxilin A(3) are expressed in lung epithelial cell lines, primary small airway epithelial cells, and human bronchial epithelial cells. Lung epithelial cells produce increased hepoxilin A(3) and lipid-derived neutrophil chemotactic activity in response to P. aeruginosa infection. Lipid-derived chemotactic activity is soluble epoxide hydrolase sensitive, consistent with hepoxilin A(3) serving a chemotactic role. Stable inhibitory structural analogs of hepoxilin A(3) are capable of impeding P. aeruginosa-induced neutrophil transepithelial migration. Finally, intranasal infection of mice with P. aeruginosa promotes enhanced cellular infiltrate into the airspace, as well as increased concentration of the 12-lipoxygenase metabolites hepoxilin A(3) and 12-hydroxyeicosa-5Z,8Z,10E,14Z-tetraenoic acid. Data generated from multiple models in this study provide further evidence that hepoxilin A(3) is produced in response to lung pathogenic bacteria and functions to drive neutrophils across epithelial barriers.
Collapse
Affiliation(s)
- David L Tamang
- Mucosal Immunology Laboratory, Massachusetts General Hospital, Charlestown, MA 02129, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|