1
|
Yu D, Lu Z, Nie F, Chong Y. Integrins regulation of wound healing processes: insights for chronic skin wound therapeutics. Front Cell Infect Microbiol 2024; 14:1324441. [PMID: 38505290 PMCID: PMC10949986 DOI: 10.3389/fcimb.2024.1324441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 02/21/2024] [Indexed: 03/21/2024] Open
Abstract
Integrins are heterodimers composed of non-covalently associated alpha and beta subunits that mediate the dynamic linkage between extracellular adhesion molecules and the intracellular actin cytoskeleton. Integrins are present in various tissues and organs and are involved in different physiological and pathological molecular responses in vivo. Wound healing is an important process in the recovery from traumatic diseases and consists of three overlapping phases: inflammation, proliferation, and remodeling. Integrin regulation acts throughout the wound healing process to promote wound healing. Prolonged inflammation may lead to failure of wound healing, such as wound chronicity. One of the main causes of chronic wound formation is bacterial colonization of the wound. In this review, we review the role of integrins in the regulation of wound healing processes such as angiogenesis and re-epithelialization, as well as the role of integrins in mediating bacterial infections during wound chronicity, and the challenges and prospects of integrins as therapeutic targets for infected wound healing.
Collapse
Affiliation(s)
- Dong Yu
- Department of Traditional Chinese Medicine, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, China
- Department of General Surgery, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, China
| | - Zhaoyu Lu
- Department of Traditional Chinese Medicine, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, China
- Department of General Surgery, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, China
| | - Fengsong Nie
- Department of Traditional Chinese Medicine, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, China
- Department of General Surgery, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, China
| | - Yang Chong
- Department of Traditional Chinese Medicine, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, China
- Department of General Surgery, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, China
| |
Collapse
|
2
|
Pasquier N, Jaulin F, Peglion F. Inverted apicobasal polarity in health and disease. J Cell Sci 2024; 137:jcs261659. [PMID: 38465512 PMCID: PMC10984280 DOI: 10.1242/jcs.261659] [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] [Indexed: 03/12/2024] Open
Abstract
Apicobasal epithelial polarity controls the functional properties of most organs. Thus, there has been extensive research on the molecular intricacies governing the establishment and maintenance of cell polarity. Whereas loss of apicobasal polarity is a well-documented phenomenon associated with multiple diseases, less is known regarding another type of apicobasal polarity alteration - the inversion of polarity. In this Review, we provide a unifying definition of inverted polarity and discuss multiple scenarios in mammalian systems and human health and disease in which apical and basolateral membrane domains are interchanged. This includes mammalian embryo implantation, monogenic diseases and dissemination of cancer cell clusters. For each example, the functional consequences of polarity inversion are assessed, revealing shared outcomes, including modifications in immune surveillance, altered drug sensitivity and changes in adhesions to neighboring cells. Finally, we highlight the molecular alterations associated with inverted apicobasal polarity and provide a molecular framework to connect these changes with the core cell polarity machinery and to explain roles of polarity inversion in health and disease. Based on the current state of the field, failure to respond to extracellular matrix (ECM) cues, increased cellular contractility and membrane trafficking defects are likely to account for most cases of inverted apicobasal polarity.
Collapse
Affiliation(s)
- Nicolas Pasquier
- Collective Invasion Team, Inserm U-1279, Gustave Roussy, Villejuif F-94805, France
- Cell Adhesion and Cancer lab, University of Turku, FI-20520 Turku, Finland
| | - Fanny Jaulin
- Collective Invasion Team, Inserm U-1279, Gustave Roussy, Villejuif F-94805, France
| | - Florent Peglion
- Collective Invasion Team, Inserm U-1279, Gustave Roussy, Villejuif F-94805, France
| |
Collapse
|
3
|
Steinbach A, Bhadkamkar V, Jimenez-Morales D, Stevenson E, Jang GM, Krogan NJ, Swaney DL, Mukherjee S. Cross-family small GTPase ubiquitination by the intracellular pathogen Legionella pneumophila. Mol Biol Cell 2024; 35:ar27. [PMID: 38117589 PMCID: PMC10916871 DOI: 10.1091/mbc.e23-06-0260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 12/04/2023] [Accepted: 12/13/2023] [Indexed: 12/22/2023] Open
Abstract
The intracellular bacterial pathogen Legionella pneumophila (L.p.) manipulates eukaryotic host ubiquitination machinery to form its replicative vacuole. While nearly 10% of L.p.'s ∼330 secreted effector proteins are ubiquitin ligases or deubiquitinases, a comprehensive measure of temporally resolved changes in the endogenous host ubiquitinome during infection has not been undertaken. To elucidate how L.p. hijacks host cell ubiquitin signaling, we generated a proteome-wide analysis of changes in protein ubiquitination during infection. We discover that L.p. infection increases ubiquitination of host regulators of subcellular trafficking and membrane dynamics, most notably ∼40% of mammalian Ras superfamily small GTPases. We determine that these small GTPases undergo nondegradative ubiquitination at the Legionella-containing vacuole (LCV) membrane. Finally, we find that the bacterial effectors SidC/SdcA play a central role in cross-family small GTPase ubiquitination, and that these effectors function upstream of SidE family ligases in the polyubiquitination and retention of GTPases in the LCV membrane. This work highlights the extensive reconfiguration of host ubiquitin signaling by bacterial effectors during infection and establishes simultaneous ubiquitination of small GTPases across the Ras superfamily as a novel consequence of L.p. infection. Our findings position L.p. as a tool to better understand how small GTPases can be regulated by ubiquitination in uninfected contexts.
Collapse
Affiliation(s)
- Adriana Steinbach
- Department of Microbiology and Immunology, University of California, San Francisco, CA 94143
- George Williams Hooper Foundation, University of California, San Francisco, CA 94143
| | - Varun Bhadkamkar
- Department of Microbiology and Immunology, University of California, San Francisco, CA 94143
- George Williams Hooper Foundation, University of California, San Francisco, CA 94143
| | - David Jimenez-Morales
- Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, CA 94158
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158
- Department of Medicine, Division of Cardiovascular Medicine, Stanford University, CA 94309
| | - Erica Stevenson
- Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, CA 94158
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158
- Quantitative Biosciences Institute, University of California, San Francisco, CA 94158
| | - Gwendolyn M. Jang
- Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, CA 94158
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158
- Quantitative Biosciences Institute, University of California, San Francisco, CA 94158
| | - Nevan J. Krogan
- Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, CA 94158
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158
- Quantitative Biosciences Institute, University of California, San Francisco, CA 94158
| | - Danielle L. Swaney
- Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, CA 94158
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158
- Quantitative Biosciences Institute, University of California, San Francisco, CA 94158
| | - Shaeri Mukherjee
- Department of Microbiology and Immunology, University of California, San Francisco, CA 94143
- George Williams Hooper Foundation, University of California, San Francisco, CA 94143
- Chan Zuckerberg Biohub, San Francisco, CA 94158
| |
Collapse
|
4
|
Savulescu AF, Peton N, Oosthuizen D, Hazra R, Rousseau RP, Mhlanga MM, Coussens AK. Quantifying spatial dynamics of Mycobacterium tuberculosis infection of human macrophages using microfabricated patterns. CELL REPORTS METHODS 2023; 3:100640. [PMID: 37963461 PMCID: PMC10694489 DOI: 10.1016/j.crmeth.2023.100640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 05/03/2023] [Accepted: 10/19/2023] [Indexed: 11/16/2023]
Abstract
Macrophages provide a first line of defense against invading pathogens, including the leading cause of bacterial mortality, Mycobacterium tuberculosis (Mtb). A challenge for quantitative characterization of host-pathogen processes in differentially polarized primary human monocyte-derived macrophages (MDMs) is their heterogeneous morphology. Here, we describe the use of microfabricated patterns that constrain the size and shape of cells, mimicking the physiological spatial confinement cells experience in tissues, to quantitatively characterize interactions during and after phagocytosis at the single-cell level at high resolution. Comparing pro-inflammatory (M1) and anti-inflammatory (M2) MDMs, we find interferon-γ stimulation increases the phagocytic contraction, while contraction and bacterial uptake decrease following silencing of phagocytosis regulator NHLRC2 or bacterial surface lipid removal. We identify host organelle position alterations within infected MDMs and differences in Mtb subcellular localization in line with M1 and M2 cellular polarity. Our approach can be adapted to study other host-pathogen interactions and coupled with downstream automated analytical approaches.
Collapse
Affiliation(s)
- Anca F Savulescu
- Division of Chemical, Systems, & Synthetic Biology, Institute for Infectious Disease & Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Observatory 7925, South Africa.
| | - Nashied Peton
- Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory 7925, South Africa; Infectious Diseases and Immune Defence Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia; Department of Pathology, University of Cape Town, Observatory 7925, South Africa
| | - Delia Oosthuizen
- Division of Chemical, Systems, & Synthetic Biology, Institute for Infectious Disease & Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Observatory 7925, South Africa
| | - Rudranil Hazra
- Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Robert P Rousseau
- Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Musa M Mhlanga
- Radboud Institute for Molecular Life Sciences (RIMLS), Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands; Epigenomics & Single Cell Biophysics Group, Department of Cell Biology, FNWI, Radboud University, 6525 GA Nijmegen, the Netherlands; Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands.
| | - Anna K Coussens
- Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory 7925, South Africa; Infectious Diseases and Immune Defence Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia; Department of Pathology, University of Cape Town, Observatory 7925, South Africa; Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia.
| |
Collapse
|
5
|
Zhu Y, Gao M, Su M, Shen Y, Zhang K, Yu B, Xu FJ. A Targeting Singlet Oxygen Battery for Multidrug-Resistant Bacterial Deep-Tissue Infections. Angew Chem Int Ed Engl 2023; 62:e202306803. [PMID: 37458367 DOI: 10.1002/anie.202306803] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 07/17/2023] [Indexed: 07/29/2023]
Abstract
Traditional photodynamic therapy (PDT) is dependent on externally applied light and oxygen, and the depth of penetration of these factors can be insufficient for the treatment of deep infections. The short half-life and short diffusion distance of reactive oxygen species (ROS) also limit the antibacterial efficiency of PDT. Herein, we designed a targeting singlet oxygen delivery system, CARG-Py, for irradiation-free and oxygen-free PDT. This system was converted to the "singlet oxygen battery" CARG-1 O2 and released singlet oxygen without external irradiation or oxygen. CARG-1 O2 is composed of pyridones coupled to a targeting peptide that improves the utilization of singlet oxygen in deep multidrug-resistant bacterial infections. CARG-1 O2 was shown to damage DNA, protein, and membranes by increasing the level of reactive oxygen inside bacteria; the attacking of multiple biomolecular sites caused the death of methicillin-resistant Staphylococcus aureus (MRSA). An in vivo study in a MRSA-infected mouse model of pneumonia demonstrated the potential of CARG-1 O2 for the efficient treatment of deep infections. This work provides a new strategy to improve traditional PDT for irradiation- and oxygen-free treatment of deep infections while improving convenience of PDT.
Collapse
Affiliation(s)
- Yiwen Zhu
- State Key Laboratory of Chemical Resource Engineering, Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education), Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Minzheng Gao
- State Key Laboratory of Chemical Resource Engineering, Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education), Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Mengrui Su
- State Key Laboratory of Chemical Resource Engineering, Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education), Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Yanzhe Shen
- State Key Laboratory of Chemical Resource Engineering, Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education), Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Kai Zhang
- State Key Laboratory of Chemical Resource Engineering, Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education), Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Bingran Yu
- State Key Laboratory of Chemical Resource Engineering, Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education), Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Fu-Jian Xu
- State Key Laboratory of Chemical Resource Engineering, Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education), Laboratory of Biomedical Materials, Beijing University of Chemical Technology, Beijing, 100029, China
| |
Collapse
|
6
|
Steinbach AM, Bhadkamkar VL, Jimenez-Morales D, Stevenson E, Jang GM, Krogan NJ, Swaney DL, Mukherjee S. Cross-family small GTPase ubiquitination by the intracellular pathogen Legionella pneumophila. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.03.551750. [PMID: 37577546 PMCID: PMC10418220 DOI: 10.1101/2023.08.03.551750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
The intracellular bacterial pathogen Legionella pneumophila (L.p.) manipulates eukaryotic host ubiquitination machinery to form its replicative vacuole. While nearly 10% of L.p.'s arsenal of ~330 secreted effector proteins have been biochemically characterized as ubiquitin ligases or deubiquitinases, a comprehensive measure of temporally resolved changes in the endogenous host ubiquitinome during infection has not been undertaken. To elucidate how L.p hijacks ubiquitin signaling within the host cell, we undertook a proteome-wide analysis of changes in protein ubiquitination during infection. We discover that L.p. infection results in increased ubiquitination of host proteins regulating subcellular trafficking and membrane dynamics, most notably 63 of ~160 mammalian Ras superfamily small GTPases. We determine that these small GTPases predominantly undergo non-degradative monoubiquitination, and link ubiquitination to recruitment to the Legionella-containing vacuole membrane. Finally, we find that the bacterial effectors SidC/SdcA play a central, but likely indirect, role in cross-family small GTPase ubiquitination. This work highlights the extensive reconfiguration of host ubiquitin signaling by bacterial effectors during infection and establishes simultaneous ubiquitination of small GTPases across the Ras superfamily as a novel consequence of L.p. infection. This work positions L.p. as a tool to better understand how small GTPases can be regulated by ubiquitination in uninfected contexts.
Collapse
Affiliation(s)
- Adriana M. Steinbach
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, United States of America
- George Williams Hooper Foundation, University of California, San Francisco, San Francisco, California, United States of America
| | - Varun L. Bhadkamkar
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, United States of America
- George Williams Hooper Foundation, University of California, San Francisco, San Francisco, California, United States of America
| | - David Jimenez-Morales
- Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, California, United States of America
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California, United States of America
- Department of Medicine, Division of Cardiovascular Medicine, Stanford University, California, United States of America
| | - Erica Stevenson
- Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, California, United States of America
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California, United States of America
- Quantitative Biosciences Institute, University of California, San Francisco, California, United States of America
| | - Gwendolyn M. Jang
- Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, California, United States of America
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California, United States of America
- Quantitative Biosciences Institute, University of California, San Francisco, California, United States of America
| | - Nevan J. Krogan
- Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, California, United States of America
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California, United States of America
- Quantitative Biosciences Institute, University of California, San Francisco, California, United States of America
| | - Danielle L. Swaney
- Gladstone Institute of Data Science and Biotechnology, J. David Gladstone Institutes, San Francisco, California, United States of America
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California, United States of America
- Quantitative Biosciences Institute, University of California, San Francisco, California, United States of America
| | - Shaeri Mukherjee
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, United States of America
- George Williams Hooper Foundation, University of California, San Francisco, San Francisco, California, United States of America
- Chan Zuckerberg Biohub, San Francisco, CA, USA
| |
Collapse
|
7
|
Tilston-Lunel AM, Varelas X. Polarity in respiratory development, homeostasis and disease. Curr Top Dev Biol 2023; 154:285-315. [PMID: 37100521 DOI: 10.1016/bs.ctdb.2023.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
Abstract
The respiratory system is composed of a multitude of cells that organize to form complex branched airways that end in alveoli, which respectively function to guide air flow and mediate gas exchange with the bloodstream. The organization of the respiratory sytem relies on distinct forms of cell polarity, which guide lung morphogenesis and patterning in development and provide homeostatic barrier protection from microbes and toxins. The stability of lung alveoli, the luminal secretion of surfactants and mucus in the airways, and the coordinated motion of multiciliated cells that generate proximal fluid flow, are all critical functions regulated by cell polarity, with defects in polarity contributing to respiratory disease etiology. Here, we summarize the current knowledge of cell polarity in lung development and homeostasis, highlighting key roles for polarity in alveolar and airway epithelial function and outlining relationships with microbial infections and diseases, such as cancer.
Collapse
|
8
|
Evaluating Bacterial Pathogenesis Using a Model of Human Airway Organoids Infected with Pseudomonas aeruginosa Biofilms. Microbiol Spectr 2022; 10:e0240822. [PMID: 36301094 PMCID: PMC9769610 DOI: 10.1128/spectrum.02408-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Pseudomonas aeruginosa is one of the leading invasive agents of human pulmonary infection, especially in patients with compromised immunity. Prior studies have used various in vitro models to establish P. aeruginosa infection and to analyze transcriptomic profiles of either the host or pathogen, and yet how much those works are relevant to the genuine human airway still raises doubts. In this study, we cultured and differentiated human airway organoids (HAOs) that recapitulate, to a large extent, the histological and physiological features of the native human mucociliary epithelium. HAOs were then employed as a host model to monitor P. aeruginosa biofilm development. Through dual-species transcriptome sequencing (RNA-seq) analyses, we found that quorum sensing (QS) and several associated protein secretion systems were significantly upregulated in HAO-associated bacteria. Cocultures of HAOs and QS-defective mutants further validated the role of QS in the maintenance of a robust biofilm and disruption of host tissue. Simultaneously, the expression magnitude of multiple inflammation-associated signaling pathways was higher in the QS mutant-infected HAOs, suggesting that QS promotes immune evasion at the transcriptional level. Altogether, modeling infection of HAOs by P. aeruginosa captured several crucial facets in host responses and bacterial pathogenesis, with QS being the most dominant virulence pathway showing profound effects on both bacterial biofilm and host immune responses. Our results revealed that HAOs are an optimal model for studying the interaction between the airway epithelium and bacterial pathogens. IMPORTANCE Human airway organoids (HAOs) are an organotypic model of human airway mucociliary epithelium. The HAOs can closely resemble their origin organ in terms of epithelium architecture and physiological function. Accumulating studies have revealed the great values of the HAO cultures in host-pathogen interaction research. In this study, HAOs were used as a host model to grow Pseudomonas aeruginosa biofilm, which is one of the most common pathogens found in pulmonary infection cases. Dual transcriptome sequencing (RNA-seq) analyses showed that the cocultures have changed the gene expression pattern of both sides significantly and simultaneously. Bacterial quorum sensing (QS), the most upregulated pathway, contributed greatly to biofilm formation, disruption of barrier function, and subversion of host immune responses. Our study therefore provides a global insight into the transcriptomic responses of both P. aeruginosa and human airway epithelium.
Collapse
|
9
|
Kudryashova E, Ankita, Ulrichs H, Shekhar S, Kudryashov DS. Pointed-end processive elongation of actin filaments by Vibrio effectors VopF and VopL. SCIENCE ADVANCES 2022; 8:eadc9239. [PMID: 36399577 PMCID: PMC9674292 DOI: 10.1126/sciadv.adc9239] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 10/03/2022] [Indexed: 07/20/2023]
Abstract
According to the cellular actin dynamics paradigm, filaments grow at their barbed ends and depolymerize predominantly from their pointed ends to form polar structures and do productive work. We show that actin can elongate at the pointed end when assisted by Vibrio VopF/L toxins, which act as processive polymerases. In cells, processively moving VopF/L speckles are inhibited by factors blocking the pointed but not barbed ends. Multispectral single-molecule imaging confirmed that VopF molecules associate with the pointed end, actively promoting its elongation even in the presence of profilin. Consequently, VopF/L can break the actin cytoskeleton's polarity by compromising actin-based cellular processes. Therefore, actin filament design allows processive growth at both ends, which suggests unforeseen possibilities for cellular actin organization, particularly in specialized cells and compartments.
Collapse
Affiliation(s)
- Elena Kudryashova
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Ankita
- Department of Physics, Emory University, Atlanta, GA 30322, USA
- Department of Cell Biology, Emory University, Atlanta, GA 30322, USA
| | - Heidi Ulrichs
- Department of Physics, Emory University, Atlanta, GA 30322, USA
- Department of Cell Biology, Emory University, Atlanta, GA 30322, USA
| | - Shashank Shekhar
- Department of Physics, Emory University, Atlanta, GA 30322, USA
- Department of Cell Biology, Emory University, Atlanta, GA 30322, USA
| | - Dmitri S. Kudryashov
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| |
Collapse
|
10
|
Mu S, Zhu Y, Wang Y, Qu S, Huang Y, Zheng L, Duan S, Yu B, Qin M, Xu FJ. Cationic Polysaccharide Conjugates as Antibiotic Adjuvants Resensitize Multidrug-Resistant Bacteria and Prevent Resistance. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2204065. [PMID: 35962720 DOI: 10.1002/adma.202204065] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 08/03/2022] [Indexed: 06/15/2023]
Abstract
In recent years, traditional antibiotic efficacy has rapidly diminished due to the advent of multidrug-resistant (MDR) bacteria, which poses severe threat to human life and globalized healthcare. Currently, the development cycle of new antibiotics cannot match the ongoing MDR infection crisis. Therefore, novel strategies are required to resensitize MDR bacteria to existing antibiotics. In this study, novel cationic polysaccharide conjugates Dextran-graft-poly(5-(1,2-dithiolan-3-yl)-N-(2-guanidinoethyl)pentanamide) (Dex-g-PSSn ) is synthesized using disulfide exchange polymerization. Critically, bacterial membranes and efflux pumps are disrupted by a sub-inhibitory concentration of Dex-g-PSS30 , which enhances rifampicin (RIF) accumulation inside bacteria and restores its efficacy. Combined Dex-g-PSS30 and RIF prevents bacterial resistance in bacteria cultured over 30 generations. Furthermore, Dex-g-PSS30 restores RIF effectiveness, reduces inflammatory reactions in a pneumonia-induced mouse model, and exhibits excellent in vivo biological absorption and degradation capabilities. As an antibiotic adjuvant, Dex-g-PSS30 provides a novel resensitizing strategy for RIF against MDR bacteria and bacterial resistance. This Dex-g-PSS30 research provides a solid platform for future MDR applications.
Collapse
Affiliation(s)
- Shaowei Mu
- State Key Laboratory of Chemical Resource Engineering Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education) and Laboratory of Biomedical Materials, Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Yiwen Zhu
- State Key Laboratory of Chemical Resource Engineering Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education) and Laboratory of Biomedical Materials, Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Yu Wang
- State Key Laboratory of Chemical Resource Engineering Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education) and Laboratory of Biomedical Materials, Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Shuang Qu
- State Key Laboratory of Chemical Resource Engineering Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education) and Laboratory of Biomedical Materials, Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Yichun Huang
- State Key Laboratory of Chemical Resource Engineering Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education) and Laboratory of Biomedical Materials, Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Liang Zheng
- State Key Laboratory of Chemical Resource Engineering Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education) and Laboratory of Biomedical Materials, Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Shun Duan
- State Key Laboratory of Chemical Resource Engineering Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education) and Laboratory of Biomedical Materials, Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Bingran Yu
- State Key Laboratory of Chemical Resource Engineering Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education) and Laboratory of Biomedical Materials, Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Meng Qin
- State Key Laboratory of Chemical Resource Engineering Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education) and Laboratory of Biomedical Materials, Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Fu-Jian Xu
- State Key Laboratory of Chemical Resource Engineering Key Lab of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology, Ministry of Education) and Laboratory of Biomedical Materials, Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| |
Collapse
|
11
|
The Lectin LecB Induces Patches with Basolateral Characteristics at the Apical Membrane to Promote Pseudomonas aeruginosa Host Cell Invasion. mBio 2022; 13:e0081922. [PMID: 35491830 PMCID: PMC9239240 DOI: 10.1128/mbio.00819-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The opportunistic bacterium Pseudomonas aeruginosa can infect mucosal tissues of the human body. To persist at the mucosal barrier, this highly adaptable pathogen has evolved many strategies, including invasion of host cells. Here, we show that the P. aeruginosa lectin LecB binds and cross-links fucosylated receptors at the apical plasma membrane of epithelial cells. This triggers a signaling cascade via Src kinases and phosphoinositide 3-kinase (PI3K), leading to the formation of patches enriched with the basolateral marker phosphatidylinositol (3,4,5)-trisphosphate (PIP3) at the apical plasma membrane. This identifies LecB as a causative bacterial factor for activating this well-known host cell response that is elicited upon apical binding of P. aeruginosa. Downstream from PI3K, Rac1 is activated to cause actin rearrangement and the outgrowth of protrusions at the apical plasma membrane. LecB-triggered PI3K activation also results in aberrant recruitment of caveolin-1 to the apical domain. In addition, we reveal a positive feedback loop between PI3K activation and apical caveolin-1 recruitment, which provides a mechanistic explanation for the previously observed implication of caveolin-1 in P. aeruginosa host cell invasion. Interestingly, LecB treatment also reversibly removes primary cilia. To directly prove the role of LecB for bacterial uptake, we coated bacterium-sized beads with LecB, which drastically enhanced their endocytosis. Furthermore, LecB deletion and LecB inhibition with l-fucose diminished the invasion efficiency of P. aeruginosa bacteria. Taken together, the results of our study identify LecB as a missing link that can explain how PI3K signaling and caveolin-1 recruitment are triggered to facilitate invasion of epithelial cells from the apical side by P. aeruginosa.
Collapse
|
12
|
Pseudomonas aeruginosa Triggered Exosomal Release of ADAM10 Mediates Proteolytic Cleavage in Trans. Int J Mol Sci 2022; 23:ijms23031259. [PMID: 35163191 PMCID: PMC8835980 DOI: 10.3390/ijms23031259] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/18/2022] [Accepted: 01/20/2022] [Indexed: 02/05/2023] Open
Abstract
Pneumonia is a life-threatening disease often caused by infection with Streptococcus pneumoniae and Pseudomonas aeruginosa. Many of the mediators (e.g., TNF, IL-6R) and junction molecules (e.g., E-cadherin) orchestrating inflammatory cell recruitment and loss of barrier integrity are proteolytically cleaved through a disintegrin and metalloproteinases (ADAMs). We could show by Western blot, surface expression analysis and measurement of proteolytic activity in cell-based assays, that ADAM10 in epithelial cells is upregulated and activated upon infection with Pseudomonas aeruginosa and Exotoxin A (ExoA), but not upon infection with Streptococcus pneumoniae. Targeting ADAM10 by pharmacological inhibition or gene silencing, we demonstrated that this activation was critical for cleavage of E-cadherin and modulated permeability and epithelial integrity. Stimulation with heat-inactivated bacteria revealed that the activation was based on the toxin repertoire rather than the interaction with the bacterial particle itself. Furthermore, calcium imaging experiments showed that the ExoA action was based on the induction of calcium influx. Investigating the extracellular vesicles and their proteolytic activity, we could show that Pseudomonas aeruginosa triggered exosomal release of ADAM10 and proteolytic cleavage in trans. This newly described mechanism could constitute an essential mechanism causing systemic inflammation in patients suffering from Pseudomonas aeruginosa-induced pneumonia stimulating future translational studies.
Collapse
|
13
|
Bronchial Epithelial Tet2 Maintains Epithelial Integrity during Acute Pseudomonas aeruginosa Pneumonia. Infect Immun 2020; 89:IAI.00603-20. [PMID: 33046509 DOI: 10.1128/iai.00603-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 10/05/2020] [Indexed: 12/23/2022] Open
Abstract
Respiratory epithelial cells are important for pulmonary innate immune responses during Pseudomonas aeruginosa infection. Tet methylcytosine dioxygenase 2 (Tet2) has been implicated in the regulation of host defense by myeloid and lymphoid cells, but whether Tet2 also contributes to epithelial responses during pneumonia is unknown. The aim of this study was to investigate the role of bronchial epithelial Tet2 in acute pneumonia caused by P. aeruginosa To this end, we crossed mice with Tet2 flanked by two Lox-P sites (Tet2fl/fl mice) with mice expressing Cre recombinase under the bronchial epithelial cell-specific Cc10 promoter (Cc10Cre mice) to generate bronchial epithelial cell-specific Tet2-deficient (Tet2fl/fl Cc10Cre ) mice. Six hours after infection with P. aeruginosa, Tet2fl/fl Cc10Cre and wild-type mice had similar bacterial loads in bronchoalveolar lavage fluid (BALF). At this time point, Tet2fl/fl Cc10Cre mice displayed reduced mRNA levels of the chemokines Cxcl1, Cxcl2, and Ccl20 in bronchial brushes. However, Cxcl1, Cxcl2, and Ccl20 protein levels and leukocyte recruitment in BALF were not different between groups. Tet2fl/fl Cc10Cre mice had increased protein levels in BALF after infection, indicating a disturbed epithelial barrier function, which was corroborated by reduced mRNA expression of tight junction protein 1 and occludin in bronchial brushes. Differences detected between Tet2fl/fl Cc10Cre and wild-type mice were no longer present at 24 h after infection. These results suggest that bronchial epithelial Tet2 contributes to maintaining epithelial integrity by enhancing intracellular connections between epithelial cells during the early phase of P. aeruginosa pneumonia.
Collapse
|
14
|
The Small RNA ErsA Plays a Role in the Regulatory Network of Pseudomonas aeruginosa Pathogenicity in Airway Infections. mSphere 2020; 5:5/5/e00909-20. [PMID: 33055260 PMCID: PMC7565897 DOI: 10.1128/msphere.00909-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial small RNAs play a remarkable role in the regulation of functions involved in host-pathogen interaction. ErsA is a small RNA of Pseudomonas aeruginosa that contributes to the regulation of bacterial virulence traits such as biofilm formation and motility. Shown to take part in a regulatory circuit under the control of the envelope stress response sigma factor σ22, ErsA targets posttranscriptionally the key virulence-associated gene algC Moreover, ErsA contributes to biofilm development and motility through the posttranscriptional modulation of the transcription factor AmrZ. Intending to evaluate the regulatory relevance of ErsA in the pathogenesis of respiratory infections, we analyzed the impact of ErsA-mediated regulation on the virulence potential of P. aeruginosa and the stimulation of the inflammatory response during the infection of bronchial epithelial cells and a murine model. Furthermore, we assessed ErsA expression in a collection of P. aeruginosa clinical pulmonary isolates and investigated the link of ErsA with acquired antibiotic resistance by generating an ersA gene deletion mutant in a multidrug-resistant P. aeruginosa strain which has long been adapted in the airways of a cystic fibrosis (CF) patient. Our results show that the ErsA-mediated regulation is relevant for the P. aeruginosa pathogenicity during acute infection and contributes to the stimulation of the host inflammatory response. Besides, ErsA was able to be subjected to selective pressure for P. aeruginosa pathoadaptation and acquirement of resistance to antibiotics commonly used in clinical practice during chronic CF infections. Our findings establish the role of ErsA as an important regulatory element in the host-pathogen interaction.IMPORTANCE Pseudomonas aeruginosa is one of the most critical multidrug-resistant opportunistic pathogens in humans, able to cause both lethal acute and chronic lung infections. Thorough knowledge of the regulatory mechanisms involved in the establishment and persistence of the airways infections by P. aeruginosa remains elusive. Emerging candidates as molecular regulators of pathogenesis in P. aeruginosa are small RNAs, which act posttranscriptionally as signal transducers of host cues. Known for being involved in the regulation of biofilm formation and responsive to envelope stress response, we show that the small RNA ErsA can play regulatory roles in acute infection, stimulation of host inflammatory response, and mechanisms of acquirement of antibiotic resistance and adaptation during the chronic lung infections of cystic fibrosis patients. Elucidating the complexity of the networks regulating host-pathogen interactions is crucial to identify novel targets for future therapeutic applications.
Collapse
|
15
|
The Pseudomonas aeruginosa Lectin LecB Causes Integrin Internalization and Inhibits Epithelial Wound Healing. mBio 2020; 11:mBio.03260-19. [PMID: 32156827 PMCID: PMC7064779 DOI: 10.1128/mbio.03260-19] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Pseudomonas aeruginosa is a ubiquitous environmental bacterium that is one of the leading causes of nosocomial infections. P. aeruginosa is able to switch between planktonic, intracellular, and biofilm-based lifestyles, which allows it to evade the immune system as well as antibiotic treatment. Hence, alternatives to antibiotic treatment are urgently required to combat P. aeruginosa infections. Lectins, like the fucose-specific LecB, are promising targets, because removal of LecB resulted in decreased virulence in mouse models. Currently, several research groups are developing LecB inhibitors. However, the role of LecB in host-pathogen interactions is not well understood. The significance of our research is in identifying cellular mechanisms of how LecB facilitates P. aeruginosa infection. We introduce LecB as a new member of the list of bacterial molecules that bind integrins and show that P. aeruginosa can move forward underneath attached epithelial cells by loosening cell-basement membrane attachment in a LecB-dependent manner. The opportunistic bacterium Pseudomonas aeruginosa produces the fucose-specific lectin LecB, which has been identified as a virulence factor. LecB has a tetrameric structure with four opposing binding sites and has been shown to act as a cross-linker. Here, we demonstrate that LecB strongly binds to the glycosylated moieties of β1-integrins on the basolateral plasma membrane of epithelial cells and causes rapid integrin endocytosis. Whereas internalized integrins were degraded via a lysosomal pathway, washout of LecB restored integrin cell surface localization, thus indicating a specific and direct action of LecB on integrins to bring about their endocytosis. Interestingly, LecB was able to trigger uptake of active and inactive β1-integrins and also of complete α3β1-integrin–laminin complexes. We provide a mechanistic explanation for this unique endocytic process by showing that LecB has the additional ability to recognize fucose-bearing glycosphingolipids and causes the formation of membrane invaginations on giant unilamellar vesicles. In cells, LecB recruited integrins to these invaginations by cross-linking integrins and glycosphingolipids. In epithelial wound healing assays, LecB specifically cleared integrins from the surface of cells located at the wound edge and blocked cell migration and wound healing in a dose-dependent manner. Moreover, the wild-type P. aeruginosa strain PAO1 was able to loosen cell-substrate adhesion in order to crawl underneath exposed cells, whereas knockout of LecB significantly reduced crawling events. Based on these results, we suggest that LecB has a role in disseminating bacteria along the cell-basement membrane interface.
Collapse
|
16
|
Huang Y, Chen CL, Yuan JJ, Li HM, Han XR, Chen RC, Guan WJ, Zhong NS. Sputum Exosomal microRNAs Profiling Reveals Critical Pathways Modulated By Pseudomonas aeruginosa Colonization In Bronchiectasis. Int J Chron Obstruct Pulmon Dis 2019; 14:2563-2573. [PMID: 31819394 PMCID: PMC6878997 DOI: 10.2147/copd.s219821] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 10/21/2019] [Indexed: 12/13/2022] Open
Abstract
Background Pseudomonas aeruginosa (PA) colonization confers poor prognosis in bronchiectasis. However, the biomarkers and biological pathways underlying these associations are unclear. Objective To identify the roles of PA colonization in bronchiectasis by exploring for sputum exosomal microRNA profiles. Methods We enrolled 98 patients with clinically stable bronchiectasis and 17 healthy subjects. Sputum was split for bacterial culture and exosomal microRNA sequencing, followed by validation with quantitative polymerase chain reaction. Bronchiectasis patients were stratified into PA and non-PA colonization groups based on sputum culture findings. We applied Gene Ontology and Kyoto Encyclopedia of Genes and Genome pathway enrichment analysis to explore biological pathways corresponding to the differentially expressed microRNAs (DEMs) associated with PA colonization. Results Eighty-two bronchiectasis patients and 9 healthy subjects yielded sufficient sputum that passed quality control. We identified 10 overlap DEMs for the comparison between bronchiectasis patients and healthy subjects, and between PA and non-PA colonization group. Both miR-92b-5p and miR-223-3p could discriminate PA colonization (C-statistic >0.60) and independently correlated with PA colonization in multiple linear regression analysis. The differential expression of miR-92b-5p was validated by quantitative polymerase chain reaction (P<0.05), whereas the differential expression of miR-223 trended towards statistical significance (P=0.06). These DEMs, whose expression levels correlated significantly with sputum inflammatory biomarkers (interleukin-1β and interleukin-8) level, were implicated in the modulation of the nuclear factor-κB, phosphatidylinositol and longevity regulation pathways. Conclusion Sputum exosomal microRNAs are implicated in PA colonization in bronchiectasis, highlighting candidate targets for therapeutic interventions to mitigate the adverse impacts conferred by PA colonization.
Collapse
Affiliation(s)
- Yan Huang
- Department of Respiratory Medicine, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute for Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, People's Republic of China
| | - Chun-Lan Chen
- Department of Respiratory Medicine, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute for Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, People's Republic of China
| | - Jing-Jing Yuan
- Department of Respiratory Medicine, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute for Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, People's Republic of China
| | - Hui-Min Li
- Department of Respiratory Medicine, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute for Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, People's Republic of China
| | - Xiao-Rong Han
- Department of Respiratory Medicine, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute for Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, People's Republic of China
| | - Rong-Chang Chen
- Department of Respiratory Medicine, Shenzhen People's Hospital, Shenzhen, Guangdong, People's Republic of China
| | - Wei-Jie Guan
- Department of Respiratory Medicine, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute for Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, People's Republic of China
| | - Nan-Shan Zhong
- Department of Respiratory Medicine, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute for Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, People's Republic of China
| |
Collapse
|
17
|
Fleiszig SMJ, Kroken AR, Nieto V, Grosser MR, Wan SJ, Metruccio MME, Evans DJ. Contact lens-related corneal infection: Intrinsic resistance and its compromise. Prog Retin Eye Res 2019; 76:100804. [PMID: 31756497 DOI: 10.1016/j.preteyeres.2019.100804] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 11/05/2019] [Accepted: 11/12/2019] [Indexed: 12/20/2022]
Abstract
Contact lenses represent a widely utilized form of vision correction with more than 140 million wearers worldwide. Although generally well-tolerated, contact lenses can cause corneal infection (microbial keratitis), with an approximate annualized incidence ranging from ~2 to ~20 cases per 10,000 wearers, and sometimes resulting in permanent vision loss. Research suggests that the pathogenesis of contact lens-associated microbial keratitis is complex and multifactorial, likely requiring multiple conspiring factors that compromise the intrinsic resistance of a healthy cornea to infection. Here, we outline our perspective of the mechanisms by which contact lens wear sometimes renders the cornea susceptible to infection, focusing primarily on our own research efforts during the past three decades. This has included studies of host factors underlying the constitutive barrier function of the healthy cornea, its response to bacterial challenge when intrinsic resistance is not compromised, pathogen virulence mechanisms, and the effects of contact lens wear that alter the outcome of host-microbe interactions. For almost all of this work, we have utilized the bacterium Pseudomonas aeruginosa because it is the leading cause of lens-related microbial keratitis. While not yet common among corneal isolates, clinical isolates of P. aeruginosa have emerged that are resistant to virtually all currently available antibiotics, leading the United States CDC (Centers for Disease Control) to add P. aeruginosa to its list of most serious threats. Compounding this concern, the development of advanced contact lenses for biosensing and augmented reality, together with the escalating incidence of myopia, could portent an epidemic of vision-threatening corneal infections in the future. Thankfully, technological advances in genomics, proteomics, metabolomics and imaging combined with emerging models of contact lens-associated P. aeruginosa infection hold promise for solving the problem - and possibly life-threatening infections impacting other tissues.
Collapse
Affiliation(s)
- Suzanne M J Fleiszig
- School of Optometry, University of California, Berkeley, CA, USA; Graduate Group in Vision Science, University of California, Berkeley, CA, USA; Graduate Groups in Microbiology and Infectious Diseases & Immunity, University of California, Berkeley, CA, USA.
| | - Abby R Kroken
- School of Optometry, University of California, Berkeley, CA, USA
| | - Vincent Nieto
- School of Optometry, University of California, Berkeley, CA, USA
| | | | - Stephanie J Wan
- Graduate Group in Vision Science, University of California, Berkeley, CA, USA
| | | | - David J Evans
- School of Optometry, University of California, Berkeley, CA, USA; College of Pharmacy, Touro University California, Vallejo, CA, USA
| |
Collapse
|
18
|
Zhao Y, Yu C, Yu Y, Wei X, Duan X, Dai X, Zhang X. Bioinspired Heteromultivalent Ligand-Decorated Nanotherapeutic for Enhanced Photothermal and Photodynamic Therapy of Antibiotic-Resistant Bacterial Pneumonia. ACS APPLIED MATERIALS & INTERFACES 2019; 11:39648-39661. [PMID: 31591880 DOI: 10.1021/acsami.9b15118] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Pseudomonas aeruginosa can cause a multitude of inflammations in humans. Due to its ability to form biofilm, the bacteria show durable resistance to drugs. Herein, we developed a heteromultivalent ligand-decorated nanotherapeutic inspired by living system for inhibition of antibiotic-resistant bacterial pneumonia. The nanotherapeutic with a heteromultivalent glycomimetic shell can specifically recognize P. aeruginosa to inhibit its biofilm formation and protect native cells from bacterial infection; the rate of biofilm inhibition was up to 85%. The nanotherapeutic with a bioresponsive hydrophobic core can protonate and control drug release in the microenvironment of bacterial infections. By utilizing these properties, the nanotherapeutics can effectively penetrate the internal structure of biofilms to release the drug, dispersing the biofilm by over 80% under laser irradiation. In vivo bioinspired nanotherapeutics have the potential to efficiently inhibit antibiotic-resistant P. aeruginosa-induced pneumonia. Collectively, we expect biomimicking systems to be the next generation of prevention and treatment as integrated antibacterial agents against P. aeruginosa.
Collapse
Affiliation(s)
- Yu Zhao
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Cong Yu
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Yunjian Yu
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Xiaosong Wei
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Xiaozhuang Duan
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Xijuan Dai
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Xinge Zhang
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| |
Collapse
|
19
|
Repression of eEF2K transcription by NF-κB tunes translation elongation to inflammation and dsDNA-sensing. Proc Natl Acad Sci U S A 2019; 116:22583-22590. [PMID: 31636182 DOI: 10.1073/pnas.1909143116] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Gene expression is rapidly remodeled by infection and inflammation in part via transcription factor NF-κB activation and regulated protein synthesis. While protein synthesis is largely controlled by mRNA translation initiation, whether cellular translation elongation factors are responsive to inflammation and infection remains poorly understood. Here, we reveal a surprising mechanism whereby NF-κB restricts phosphorylation of the critical translation elongation factor eEF2, which catalyzes the protein synthesis translocation step. Upon exposure to NF-κB-activating stimuli, including TNFα, human cytomegalovirus infection, or double-stranded DNA, eEF2 phosphorylation on Thr56, which slows elongation to limit protein synthesis, and the overall abundance of eEF2 kinase (eEF2K) are reduced. Significantly, this reflected a p65 NF-κB subunit-dependent reduction in eEF2K pre-mRNA, indicating that NF-κB activation represses eEF2K transcription to decrease eEF2K protein levels. Finally, we demonstrate that reducing eEF2K abundance regulates protein synthesis in response to a bacterial toxin that inactivates eEF2. This establishes that NF-κB activation by diverse physiological effectors controls eEF2 activity via a transcriptional repression mechanism that reduces eEF2K polypeptide abundance to preclude eEF2 phosphorylation, thereby stimulating translation elongation and protein synthesis. Moreover, it illustrates how nuclear transcription regulation shapes translation elongation factor activity and exposes how eEF2 is integrated into innate immune response networks orchestrated by NF-κB.
Collapse
|
20
|
Elkhawaga AA, Khalifa MM, El-Badawy O, Hassan MA, El-Said WA. Rapid and highly sensitive detection of pyocyanin biomarker in different Pseudomonas aeruginosa infections using gold nanoparticles modified sensor. PLoS One 2019; 14:e0216438. [PMID: 31361746 PMCID: PMC6667159 DOI: 10.1371/journal.pone.0216438] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 07/17/2019] [Indexed: 12/19/2022] Open
Abstract
Successful antibiotic treatment of infections relies on accurate and rapid identification of the infectious agents. Pseudomonas aeruginosa is implicated in a wide range of human infections that mostly become complicated and life threating, especially in immunocompromised and critically ill patients. Conventional microbiological methods take more than three days to obtain accurate results. Pyocyanin is a distinctive electroactive biomarker for Pseudomonas aeruginosa. Here, we have prepared polyaniline/gold nanoparticles decorated ITO electrode and tested it to establish a rapid, diagnostic and highly sensitive pyocyanin sensor in a culture of Pseudomonas aeruginosa clinical isolates with high selectivity for traces of pyocyanin when measured in the existence of different interferences like vitamin C, uric acid, and glucose. The scanning electron microscopy and cyclic voltammetry techniques were used to characterize the morphology and electrical conductivity of the constructed electrode. The determined linear range for pyocyanin detection was from 238 μM to 1.9 μM with a detection limit of 500 nM. Compared to the screen-printed electrode used before, the constructed electrode showed a 4-fold enhanced performance. Furthermore, PANI/Au NPs/ITO modified electrodes have demonstrated the ability to detect pyocyanin directly in Pseudomonas aeruginosa culture without any potential interference with other species.
Collapse
Affiliation(s)
- Amal A Elkhawaga
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Marwa M Khalifa
- Department of Microbiology and Immunology, Faculty of Pharmacy, Assiut University, Assiut, Egypt
| | - Omnia El-Badawy
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Mona A Hassan
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Waleed A El-Said
- Chemistry Department, Faculty of Science, Assiut University, Assiut, Egypt
| |
Collapse
|
21
|
Zhao Y, Guo Q, Dai X, Wei X, Yu Y, Chen X, Li C, Cao Z, Zhang X. A Biomimetic Non-Antibiotic Approach to Eradicate Drug-Resistant Infections. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1806024. [PMID: 30589118 PMCID: PMC6634980 DOI: 10.1002/adma.201806024] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Revised: 11/26/2018] [Indexed: 05/19/2023]
Abstract
The chronic infections by pathogenic Pseudomonas aeruginosa (P. aeruginosa) remain to be properly addressed. In particular, for drug-resistant strains, limited medication is available. An in vivo pneumonia model induced by a clinically isolated aminoglycoside resistant strain of P. aeruginosa is developed. Tobramycin clinically treating P. aeruginosa infections is found to be ineffective to inhibit or eliminate this drug-resistant strain. Here, a newly developed non-antibiotics based nanoformulation plus near-infrared (NIR) photothermal treatment shows a remarkable antibacterial efficacy in treating this drug-resistant pneumonia. The novel formulation contains 50-100 nm long nanorods decorated with two types of glycomimetic polymers to specifically block bacterial LecA and LecB lectins, respectively, which are essential for bacterial biofilm development. Such a 3D display of heteromultivalent glycomimetics on a large scale is inspired by the natural strengthening mechanism for the carbohydrate-lectin interaction that occurs when bacteria initially infects the host. This novel formulation shows the most efficient bacteria inhabitation and killing against P. aeruginosa infection, through lectin blocking and the near-infrared-light-induced photothermal effect of gold nanorods, respectively. Collectively, the novel biomimetic design combined with the photothermal killing capability is expected to be an alternative treatment strategy against the ever-threatening drug-resistant infectious diseases when known antibiotics have failed.
Collapse
Affiliation(s)
- Yu Zhao
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Qianqian Guo
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xiaomei Dai
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xiaosong Wei
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Yunjian Yu
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xuelei Chen
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Chaoxing Li
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Zhiqiang Cao
- Department of Chemical Engineering and Materials Science, Wayne State University, Detroit, Michigan 48202, USA
| | - Xinge Zhang
- Key Laboratory of Functional Polymer Materials of Ministry Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| |
Collapse
|
22
|
Vorhagen S, Kleefisch D, Persa OD, Graband A, Schwickert A, Saynisch M, Leitges M, Niessen CM, Iden S. Shared and independent functions of aPKCλ and Par3 in skin tumorigenesis. Oncogene 2018; 37:5136-5146. [PMID: 29789715 PMCID: PMC6137026 DOI: 10.1038/s41388-018-0313-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 03/04/2018] [Accepted: 04/17/2018] [Indexed: 12/11/2022]
Abstract
The polarity proteins Par3 and aPKC are key regulators of processes altered in cancer. Par3/aPKC are thought to dynamically interact with Par6 but increasing evidence suggests that aPKC and Par3 also exert complex-independent functions. Whereas aPKCλ serves as tumor promotor, Par3 can either promote or suppress tumorigenesis. Here we asked whether and how Par3 and aPKCλ genetically interact to control two-stage skin carcinogenesis. Epidermal loss of Par3, aPKCλ, or both, strongly reduced tumor multiplicity and increased latency but inhibited invasion to similar extents, indicating that Par3 and aPKCλ function as a complex to promote tumorigenesis. Molecularly, Par3/aPKCλ cooperate to promote Akt, ERK and NF-κB signaling during tumor initiation to sustain growth, whereas aPKCλ dominates in promoting survival. In the inflammatory tumorigenesis phase Par3/aPKCλ cooperate to drive Stat3 activation and hyperproliferation. Unexpectedly, the reduced inflammatory signaling did not alter carcinogen-induced immune cell numbers but reduced IL-4 Receptor-positive stromal macrophage numbers in all mutant mice, suggesting that epidermal aPKCλ and Par3 promote a tumor-permissive environment. Importantly, aPKCλ also serves a distinct, carcinogen-independent role in controlling skin immune cell homeostasis. Collectively, our data demonstrates that Par3 and aPKCλ cooperate to promote skin tumor initiation and progression, likely through sustaining growth, survival, and inflammatory signaling.
Collapse
Affiliation(s)
- Susanne Vorhagen
- Department of Dermatology, University of Cologne, Köln, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Köln, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, Köln, Germany
| | - Dominik Kleefisch
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Köln, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, Köln, Germany
| | - Oana-Diana Persa
- Department of Dermatology, University of Cologne, Köln, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Köln, Germany
| | - Annika Graband
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Köln, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, Köln, Germany
| | - Alexandra Schwickert
- Department of Dermatology, University of Cologne, Köln, Germany.,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Köln, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, Köln, Germany
| | - Michael Saynisch
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Köln, Germany.,Center for Molecular Medicine Cologne (CMMC), University of Cologne, Köln, Germany
| | - Michael Leitges
- Biotechnology Centre of Oslo, University of Oslo, 0316, Oslo, Norway
| | - Carien M Niessen
- Department of Dermatology, University of Cologne, Köln, Germany. .,Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Köln, Germany. .,Center for Molecular Medicine Cologne (CMMC), University of Cologne, Köln, Germany.
| | - Sandra Iden
- Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Köln, Germany. .,Center for Molecular Medicine Cologne (CMMC), University of Cologne, Köln, Germany.
| |
Collapse
|
23
|
Golovkine G, Reboud E, Huber P. Pseudomonas aeruginosa Takes a Multi-Target Approach to Achieve Junction Breach. Front Cell Infect Microbiol 2018; 7:532. [PMID: 29379773 PMCID: PMC5770805 DOI: 10.3389/fcimb.2017.00532] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 12/20/2017] [Indexed: 01/17/2023] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen which uses a number of strategies to cross epithelial and endothelial barriers at cell–cell junctions. In this review, we describe how the coordinated actions of P. aeruginosa's virulence factors trigger various molecular mechanisms to disarm the junctional gate responsible for tissue integrity.
Collapse
Affiliation(s)
- Guillaume Golovkine
- Centre National de la Recherche Scientifique ERL5261, CEA BIG-BCI, Institut National de la Santé et de la Recherche Médicale UMR1036, Université Grenoble Alpes, Grenoble, France
| | - Emeline Reboud
- Centre National de la Recherche Scientifique ERL5261, CEA BIG-BCI, Institut National de la Santé et de la Recherche Médicale UMR1036, Université Grenoble Alpes, Grenoble, France
| | - Philippe Huber
- Centre National de la Recherche Scientifique ERL5261, CEA BIG-BCI, Institut National de la Santé et de la Recherche Médicale UMR1036, Université Grenoble Alpes, Grenoble, France
| |
Collapse
|
24
|
Tapia R, Kralicek SE, Hecht GA. Modulation of epithelial cell polarity by bacterial pathogens. Ann N Y Acad Sci 2017. [PMID: 28628193 DOI: 10.1111/nyas.13388] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Epithelial cells constitute a physical barrier that aids in protecting the host from microbial pathogens. Polarized epithelial cells contain distinct apical and basolateral membrane domains separated by intercellular junctions, including tight junctions (TJs), which contribute to the maintenance of apical-basal polarity. Polarity complexes also contribute to the establishment of TJ formation. Several pathogens perturb epithelial TJ barrier function and structure in addition to causing a loss of apical-basal polarity. Here, we review the impact of pathogenic bacteria on the disruption of cell-cell junctions and epithelial polarity.
Collapse
Affiliation(s)
- Rocio Tapia
- Division of Gastroenterology and Nutrition, Department of Medicine, Loyola University Chicago, Maywood, Illinois
| | - Sarah E Kralicek
- Division of Gastroenterology and Nutrition, Department of Medicine, Loyola University Chicago, Maywood, Illinois
| | - Gail A Hecht
- Division of Gastroenterology and Nutrition, Department of Medicine, Loyola University Chicago, Maywood, Illinois.,Department of Microbiology and Immunology, Loyola University Chicago, Maywood, Illinois.,Edward Hines Jr. VA Hospital, Hines, Illinois
| |
Collapse
|
25
|
Ruch TR, Engel JN. Targeting the Mucosal Barrier: How Pathogens Modulate the Cellular Polarity Network. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a027953. [PMID: 28193722 DOI: 10.1101/cshperspect.a027953] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The mucosal barrier is composed of polarized epithelial cells with distinct apical and basolateral surfaces separated by tight junctions and serves as both a physical and immunological barrier to incoming pathogens. Specialized polarity proteins are critical for establishment and maintenance of polarity. Many human pathogens have evolved virulence mechanisms that target the polarity network to enhance binding, create replication niches, move through the barrier by transcytosis, or bypass the barrier by disrupting cell-cell junctions. This review summarizes recent advances and compares and contrasts how three important human pathogens that colonize mucosal surfaces, Pseudomonas aeruginosa, Helicobacter pylori, and Neisseria meningitidis, subvert the host cell polarization machinery during infection.
Collapse
Affiliation(s)
- Travis R Ruch
- Department of Medicine, University of California, San Francisco, San Francisco, California 94143
| | - Joanne N Engel
- Department of Medicine, University of California, San Francisco, San Francisco, California 94143.,Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California 94143
| |
Collapse
|
26
|
Crabbé A, Liu Y, Matthijs N, Rigole P, De La Fuente-Nùñez C, Davis R, Ledesma MA, Sarker S, Van Houdt R, Hancock REW, Coenye T, Nickerson CA. Antimicrobial efficacy against Pseudomonas aeruginosa biofilm formation in a three-dimensional lung epithelial model and the influence of fetal bovine serum. Sci Rep 2017; 7:43321. [PMID: 28256611 PMCID: PMC5335707 DOI: 10.1038/srep43321] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 01/25/2017] [Indexed: 12/14/2022] Open
Abstract
In vitro models that mimic in vivo host-pathogen interactions are needed to evaluate candidate drugs that inhibit bacterial virulence traits. We established a new approach to study Pseudomonas aeruginosa biofilm susceptibility on biotic surfaces, using a three-dimensional (3-D) lung epithelial cell model. P. aeruginosa formed antibiotic resistant biofilms on 3-D cells without affecting cell viability. The biofilm-inhibitory activity of antibiotics and/or the anti-biofilm peptide DJK-5 were evaluated on 3-D cells compared to a plastic surface, in medium with and without fetal bovine serum (FBS). In both media, aminoglycosides were more efficacious in the 3-D cell model. In serum-free medium, most antibiotics (except polymyxins) showed enhanced efficacy when 3-D cells were present. In medium with FBS, colistin was less efficacious in the 3-D cell model. DJK-5 exerted potent inhibition of P. aeruginosa association with both substrates, only in serum-free medium. DJK-5 showed stronger inhibitory activity against P. aeruginosa associated with plastic compared to 3-D cells. The combined addition of tobramycin and DJK-5 exhibited more potent ability to inhibit P. aeruginosa association with both substrates. In conclusion, lung epithelial cells influence the efficacy of most antimicrobials against P. aeruginosa biofilm formation, which in turn depends on the presence or absence of FBS.
Collapse
Affiliation(s)
- Aurélie Crabbé
- Laboratory of Pharmaceutical Microbiology (LPM), Ghent University, Ghent, Belgium.,The Biodesign Institute, Center for Infectious Diseases and Vaccinology, Arizona State University, Tempe, Arizona, United States of America
| | - Yulong Liu
- The Biodesign Institute, Center for Infectious Diseases and Vaccinology, Arizona State University, Tempe, Arizona, United States of America
| | - Nele Matthijs
- Laboratory of Pharmaceutical Microbiology (LPM), Ghent University, Ghent, Belgium
| | - Petra Rigole
- Laboratory of Pharmaceutical Microbiology (LPM), Ghent University, Ghent, Belgium
| | - César De La Fuente-Nùñez
- University of British Columbia, Centre for Microbial Diseases and Immunity Research, Vancouver, British Columbia, Canada
| | - Richard Davis
- The Biodesign Institute, Center for Infectious Diseases and Vaccinology, Arizona State University, Tempe, Arizona, United States of America
| | - Maria A Ledesma
- The Biodesign Institute, Center for Infectious Diseases and Vaccinology, Arizona State University, Tempe, Arizona, United States of America
| | - Shameema Sarker
- The Biodesign Institute, Center for Infectious Diseases and Vaccinology, Arizona State University, Tempe, Arizona, United States of America
| | - Rob Van Houdt
- Unit of Microbiology, Belgian Nuclear Research Centre (SCK·CEN), Mol, Belgium
| | - Robert E W Hancock
- University of British Columbia, Centre for Microbial Diseases and Immunity Research, Vancouver, British Columbia, Canada
| | - Tom Coenye
- Laboratory of Pharmaceutical Microbiology (LPM), Ghent University, Ghent, Belgium
| | - Cheryl A Nickerson
- The Biodesign Institute, Center for Infectious Diseases and Vaccinology, Arizona State University, Tempe, Arizona, United States of America.,School of Life Sciences, Arizona State University, Tempe, Arizona 85287, United States of America
| |
Collapse
|
27
|
Lin CK, Kazmierczak BI. Inflammation: A Double-Edged Sword in the Response to Pseudomonas aeruginosa Infection. J Innate Immun 2017; 9:250-261. [PMID: 28222444 DOI: 10.1159/000455857] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 01/05/2017] [Indexed: 12/22/2022] Open
Abstract
The Gram-negative opportunistic pathogen Pseudomonas aeruginosa exploits failures of barrier defense and innate immunity to cause acute infections at a range of anatomic sites. We review the defense mechanisms that normally protect against P. aeruginosa pulmonary infection, as well as the bacterial products and activities that trigger their activation. Innate immune recognition of P. aeruginosa is critical for pathogen clearance; nonetheless, inflammation is also associated with pathogen persistence and poor host outcomes. We describe P. aeruginosa adaptations that improve this pathogen's fitness in the inflamed airway, and briefly discuss strategies to manipulate inflammation to benefit the host. Such adjunct therapies may become increasingly important in the treatment of acute and chronic infections caused by this multi-drug-resistant pathogen.
Collapse
|
28
|
Tang Y, Ali Z, Zou J, Jin G, Zhu J, Yang J, Dai J. Detection methods for Pseudomonas aeruginosa: history and future perspective. RSC Adv 2017. [DOI: 10.1039/c7ra09064a] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The current review summarized and analyzed the development of detection techniques forPseudomonas aeruginosaover the past 50 years.
Collapse
Affiliation(s)
- Yongjun Tang
- School of Applied Chemistry and Biotechnology
- Shenzhen Polytechnic
- Shenzhen 518055
- China
| | - Zeeshan Ali
- School of Applied Chemistry and Biotechnology
- Shenzhen Polytechnic
- Shenzhen 518055
- China
| | - Jun Zou
- School of Chemistry and Chemical Engineering
- Hunan Institute of Engineering
- Xiangtan 411104
- China
| | - Gang Jin
- School of Applied Chemistry and Biotechnology
- Shenzhen Polytechnic
- Shenzhen 518055
- China
| | - Junchen Zhu
- School of Applied Chemistry and Biotechnology
- Shenzhen Polytechnic
- Shenzhen 518055
- China
| | - Jian Yang
- School of Applied Chemistry and Biotechnology
- Shenzhen Polytechnic
- Shenzhen 518055
- China
| | - Jianguo Dai
- School of Applied Chemistry and Biotechnology
- Shenzhen Polytechnic
- Shenzhen 518055
- China
| |
Collapse
|
29
|
Ruch TR, Bryant DM, Mostov KE, Engel JN. Par3 integrates Tiam1 and phosphatidylinositol 3-kinase signaling to change apical membrane identity. Mol Biol Cell 2016; 28:252-260. [PMID: 27881661 PMCID: PMC5231894 DOI: 10.1091/mbc.e16-07-0541] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 11/16/2016] [Accepted: 11/18/2016] [Indexed: 01/31/2023] Open
Abstract
Pathogens can alter epithelial polarity by recruiting polarity proteins to the apical membrane, but how a change in protein localization is linked to polarity disruption is not clear. In this study, we used chemically induced dimerization to rapidly relocalize proteins from the cytosol to the apical surface. We demonstrate that forced apical localization of Par3, which is normally restricted to tight junctions, is sufficient to alter apical membrane identity through its interactions with phosphatidylinositol 3-kinase (PI3K) and the Rac1 guanine nucleotide exchange factor Tiam1. We further show that PI3K activity is required upstream of Rac1, and that simultaneously targeting PI3K and Tiam1 to the apical membrane has a synergistic effect on membrane remodeling. Thus, Par3 coordinates the action of PI3K and Tiam1 to define membrane identity, revealing a signaling mechanism that can be exploited by human mucosal pathogens.
Collapse
Affiliation(s)
- Travis R Ruch
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143
| | - David M Bryant
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94158.,Cancer Research UK Beatson Institute, University of Glasgow, Glasgow G61 1BD, United Kingdom.,Institute of Cancer Sciences, University of Glasgow, Glasgow G61 1BD, United Kingdom
| | - Keith E Mostov
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94158.,Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158
| | - Joanne N Engel
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143
| |
Collapse
|
30
|
Schwarzer C, Fischer H, Machen TE. Chemotaxis and Binding of Pseudomonas aeruginosa to Scratch-Wounded Human Cystic Fibrosis Airway Epithelial Cells. PLoS One 2016; 11:e0150109. [PMID: 27031335 PMCID: PMC4816407 DOI: 10.1371/journal.pone.0150109] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 02/09/2016] [Indexed: 11/18/2022] Open
Abstract
Confocal imaging was used to characterize interactions of Pseudomonas aeruginosa (PA, expressing GFP or labeled with Syto 11) with CF airway epithelial cells (CFBE41o-, grown as confluent monolayers with unknown polarity on coverglasses) in control conditions and following scratch wounding. Epithelia and PAO1-GFP or PAK-GFP (2 MOI) were incubated with Ringer containing typical extracellular salts, pH and glucose and propidium iodide (PI, to identify dead cells). PAO1 and PAK swam randomly over and did not bind to nonwounded CFBE41o- cells. PA migrated rapidly (began within 20 sec, maximum by 5 mins) and massively (10–80 fold increase, termed “swarming”), but transiently (random swimming after 15 mins), to wounds, particularly near cells that took up PI. Some PA remained immobilized on cells near the wound. PA swam randomly over intact CFBE41o- monolayers and wounded monolayers that had been incubated with medium for 1 hr. Expression of CFTR and altered pH of the media did not affect PA interactions with CFBE41o- wounds. In contrast, PAO1 swarming and immobilization along wounds was abolished in PAO1 (PAO1ΔcheYZABW, no expression of chemotaxis regulatory components cheY, cheZ, cheA, cheB and cheW) and greatly reduced in PAO1 that did not express amino acid receptors pctA, B and C (PAO1ΔpctABC) and in PAO1 incubated in Ringer containing a high concentration of mixed amino acids. Non-piliated PAKΔpilA swarmed normally towards wounded areas but bound infrequently to CFBE41o- cells. In contrast, both swarming and binding of PA to CFBE41o- cells near wounds were prevented in non-flagellated PAKΔfliC. Data are consistent with the idea that (i) PA use amino acid sensor-driven chemotaxis and flagella-driven swimming to swarm to CF airway epithelial cells near wounds and (ii) PA use pili to bind to epithelial cells near wounds.
Collapse
Affiliation(s)
- Christian Schwarzer
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
| | - Horst Fischer
- Children’s Hospital Oakland Research Institute, Oakland, California, United States of America
| | - Terry E. Machen
- Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America
- * E-mail:
| |
Collapse
|
31
|
Parker D, Ahn D, Cohen T, Prince A. Innate Immune Signaling Activated by MDR Bacteria in the Airway. Physiol Rev 2016; 96:19-53. [PMID: 26582515 DOI: 10.1152/physrev.00009.2015] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Health care-associated bacterial pneumonias due to multiple-drug resistant (MDR) pathogens are an important public health problem and are major causes of morbidity and mortality worldwide. In addition to antimicrobial resistance, these organisms have adapted to the milieu of the human airway and have acquired resistance to the innate immune clearance mechanisms that normally prevent pneumonia. Given the limited efficacy of antibiotics, bacterial clearance from the airway requires an effective immune response. Understanding how specific airway pathogens initiate and regulate innate immune signaling, and whether this response is excessive, leading to host-induced pathology may guide future immunomodulatory therapy. We will focus on three of the most important causes of health care-associated pneumonia, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae, and review the mechanisms through which an inappropriate or damaging innate immune response is stimulated, as well as describe how airway pathogens cause persistent infection by evading immune activation.
Collapse
Affiliation(s)
- Dane Parker
- Departments of Pediatrics and Pharmacology, Columbia University, New York, New York
| | - Danielle Ahn
- Departments of Pediatrics and Pharmacology, Columbia University, New York, New York
| | - Taylor Cohen
- Departments of Pediatrics and Pharmacology, Columbia University, New York, New York
| | - Alice Prince
- Departments of Pediatrics and Pharmacology, Columbia University, New York, New York
| |
Collapse
|
32
|
Cott C, Thuenauer R, Landi A, Kühn K, Juillot S, Imberty A, Madl J, Eierhoff T, Römer W. Pseudomonas aeruginosa lectin LecB inhibits tissue repair processes by triggering β-catenin degradation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:1106-18. [PMID: 26862060 PMCID: PMC4859328 DOI: 10.1016/j.bbamcr.2016.02.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Revised: 01/31/2016] [Accepted: 02/05/2016] [Indexed: 01/08/2023]
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen that induces severe lung infections such as ventilator-associated pneumonia and acute lung injury. Under these conditions, the bacterium diminishes epithelial integrity and inhibits tissue repair mechanisms, leading to persistent infections. Understanding the involved bacterial virulence factors and their mode of action is essential for the development of new therapeutic approaches. In our study we discovered a so far unknown effect of the P. aeruginosa lectin LecB on host cell physiology. LecB alone was sufficient to attenuate migration and proliferation of human lung epithelial cells and to induce transcriptional activity of NF-κB. These effects are characteristic of impaired tissue repair. Moreover, we found a strong degradation of β-catenin, which was partially recovered by the proteasome inhibitor lactacystin. In addition, LecB induced loss of cell-cell contacts and reduced expression of the β-catenin targets c-myc and cyclin D1. Blocking of LecB binding to host cell plasma membrane receptors by soluble l-fucose prevented these changes in host cell behavior and signaling, and thereby provides a powerful strategy to suppress LecB function. Our findings suggest that P. aeruginosa employs LecB as a virulence factor to induce β-catenin degradation, which then represses processes that are directly linked to tissue recovery.
Collapse
Affiliation(s)
- Catherine Cott
- Faculty of Biology, Schänzlestraße 1, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Schänzlestraße 18, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Roland Thuenauer
- Faculty of Biology, Schänzlestraße 1, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Schänzlestraße 18, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Alessia Landi
- Faculty of Biology, Schänzlestraße 1, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Schänzlestraße 18, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Katja Kühn
- Faculty of Biology, Schänzlestraße 1, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Schänzlestraße 18, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Samuel Juillot
- Faculty of Biology, Schänzlestraße 1, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Schänzlestraße 18, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany; Spemann Graduate School of Biology and Medicine (SGBM), Albert-Ludwigs-University Freiburg, Albertstraße 19, 79104 Freiburg, Germany
| | - Anne Imberty
- Centre de Recherches sur les Macromolécules Végétales, UPR5301 CNRS and University of Grenoble Alpes, BP53, 38041 Grenoble cédex 09, France
| | - Josef Madl
- Faculty of Biology, Schänzlestraße 1, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Schänzlestraße 18, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Thorsten Eierhoff
- Faculty of Biology, Schänzlestraße 1, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Schänzlestraße 18, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Winfried Römer
- Faculty of Biology, Schänzlestraße 1, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, Schänzlestraße 18, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany; Spemann Graduate School of Biology and Medicine (SGBM), Albert-Ludwigs-University Freiburg, Albertstraße 19, 79104 Freiburg, Germany.
| |
Collapse
|
33
|
Kazmierczak BI, Schniederberend M, Jain R. Cross-regulation of Pseudomonas motility systems: the intimate relationship between flagella, pili and virulence. Curr Opin Microbiol 2015; 28:78-82. [PMID: 26476804 DOI: 10.1016/j.mib.2015.07.017] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Revised: 07/27/2015] [Accepted: 07/29/2015] [Indexed: 10/22/2022]
Abstract
Pseudomonas aeruginosa navigates using two distinct forms of motility, swimming and twitching. A polar flagellum and Type 4 pili power these movements, respectively, allowing P. aeruginosa to attach to and colonize surfaces. Single cell imaging and particle tracking algorithms have revealed a wide range of bacterial surface behaviors which are regulated by second messengers cyclic-di-GMP and cAMP; the production of these signals is, in turn, responsive to the engagement of motility organelles with a surface. Innate immune defense systems, long known to recognize structural components of flagella, appear to respond to motility itself. The association of motility with both upregulation of virulence and induction of host defense mechanisms underlies the complex contributions of flagella and pili to P. aeruginosa pathogenesis.
Collapse
Affiliation(s)
- Barbara I Kazmierczak
- Department of Microbial Pathogenesis, Yale University School of Medicine, 333 Cedar St., New Haven, CT 06520-8022, USA; Department of Medicine (Infectious Diseases), Yale University School of Medicine, 333 Cedar St., New Haven, CT 06520-8022, USA.
| | - Maren Schniederberend
- Department of Medicine (Infectious Diseases), Yale University School of Medicine, 333 Cedar St., New Haven, CT 06520-8022, USA
| | - Ruchi Jain
- Department of Medicine (Infectious Diseases), Yale University School of Medicine, 333 Cedar St., New Haven, CT 06520-8022, USA
| |
Collapse
|
34
|
The adherens junctions control susceptibility to Staphylococcus aureus α-toxin. Proc Natl Acad Sci U S A 2015; 112:14337-42. [PMID: 26489655 DOI: 10.1073/pnas.1510265112] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Staphylococcus aureus is both a transient skin colonizer and a formidable human pathogen, ranking among the leading causes of skin and soft tissue infections as well as severe pneumonia. The secreted bacterial α-toxin is essential for S. aureus virulence in these epithelial diseases. To discover host cellular factors required for α-toxin cytotoxicity, we conducted a genetic screen using mutagenized haploid human cells. Our screen identified a cytoplasmic member of the adherens junctions, plekstrin-homology domain containing protein 7 (PLEKHA7), as the second most significantly enriched gene after the known α-toxin receptor, a disintegrin and metalloprotease 10 (ADAM10). Here we report a new, unexpected role for PLEKHA7 and several components of cellular adherens junctions in controlling susceptibility to S. aureus α-toxin. We find that despite being injured by α-toxin pore formation, PLEKHA7 knockout cells recover after intoxication. By infecting PLEKHA7(-/-) mice with methicillin-resistant S. aureus USA300 LAC strain, we demonstrate that this junctional protein controls disease severity in both skin infection and lethal S. aureus pneumonia. Our results suggest that adherens junctions actively control cellular responses to a potent pore-forming bacterial toxin and identify PLEKHA7 as a potential nonessential host target to reduce S. aureus virulence during epithelial infections.
Collapse
|
35
|
Guyer RA, Macara IG. Loss of the polarity protein PAR3 activates STAT3 signaling via an atypical protein kinase C (aPKC)/NF-κB/interleukin-6 (IL-6) axis in mouse mammary cells. J Biol Chem 2015; 290:8457-68. [PMID: 25657002 DOI: 10.1074/jbc.m114.621011] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
PAR3 suppresses tumor growth and metastasis in vivo and cell invasion through matrix in vitro. We propose that PAR3 organizes and limits multiple signaling pathways and that inappropriate activation of these pathways occurs without PAR3. Silencing Pard3 in conjunction with oncogenic activation promotes invasion and metastasis via constitutive STAT3 activity in mouse models, but the mechanism for this is unknown. We now show that loss of PAR3 triggers increased production of interleukin-6, which induces STAT3 signaling in an autocrine manner. Activation of atypical protein kinase C ι/λ (aPKCι/λ) mediates this effect by stimulating NF-κB signaling and IL-6 expression. Our results suggest that PAR3 restrains aPKCι/λ activity and thus prevents aPKCι/λ from activating an oncogenic signaling network.
Collapse
Affiliation(s)
- Richard A Guyer
- From the Department of Cell and Developmental Biology and Medical-Scientist Training Program, Vanderbilt University, Nashville, Tennessee 37232
| | - Ian G Macara
- From the Department of Cell and Developmental Biology and
| |
Collapse
|
36
|
Tran CS, Rangel SM, Almblad H, Kierbel A, Givskov M, Tolker-Nielsen T, Hauser AR, Engel JN. The Pseudomonas aeruginosa type III translocon is required for biofilm formation at the epithelial barrier. PLoS Pathog 2014; 10:e1004479. [PMID: 25375398 PMCID: PMC4223071 DOI: 10.1371/journal.ppat.1004479] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 09/18/2014] [Indexed: 12/24/2022] Open
Abstract
Clinical infections by Pseudomonas aeruginosa, a deadly Gram-negative, opportunistic pathogen of immunocompromised hosts, often involve the formation of antibiotic-resistant biofilms. Although biofilm formation has been extensively studied in vitro on glass or plastic surfaces, much less is known about biofilm formation at the epithelial barrier. We have previously shown that when added to the apical surface of polarized epithelial cells, P. aeruginosa rapidly forms cell-associated aggregates within 60 minutes of infection. By confocal microscopy we now show that cell-associated aggregates exhibit key characteristics of biofilms, including the presence of extracellular matrix and increased resistance to antibiotics compared to planktonic bacteria. Using isogenic mutants in the type III secretion system, we found that the translocon, but not the effectors themselves, were required for cell-associated aggregation on the surface of polarized epithelial cells and at early time points in a murine model of acute pneumonia. In contrast, the translocon was not required for aggregation on abiotic surfaces, suggesting a novel function for the type III secretion system during cell-associated aggregation. Supernatants from epithelial cells infected with wild-type bacteria or from cells treated with the pore-forming toxin streptolysin O could rescue aggregate formation in a type III secretion mutant, indicating that cell-associated aggregation requires one or more host cell factors. Our results suggest a previously unappreciated function for the type III translocon in the formation of P. aeruginosa biofilms at the epithelial barrier and demonstrate that biofilms may form at early time points of infection. Clinical infections by Pseudomonas aeruginosa, a deadly Gram-negative, opportunistic pathogen of immunocompromised patients, involve the formation of antibiotic-resistant biofilms. Although P. aeruginosa biofilm formation has been extensively studied on glass or plastic surfaces, less is known about biofilm formation at the epithelial barrier. This study shows that, on epithelial cells, P. aeruginosa forms aggregates that exhibit key characteristics of biofilms. Furthermore, we demonstrate that aggregation on epithelial cells and at early time points in mouse pneumonia requires pore formation mediated by the type III secretion system. Our results indicate that biofilm-like aggregation is induced by a host cell factor that is released after pore formation, suggesting an unexpected role for an acute virulence factor in biofilm formation.
Collapse
Affiliation(s)
- Cindy S Tran
- Department of Pediatrics, University of California San Francisco, San Francisco, California, United States of America
| | - Stephanie M Rangel
- Department of Microbiology-Immunology, Northwestern University, Chicago, Illinois, United States of America
| | - Henrik Almblad
- Costern Biofilm Center, Department of International Health, Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Michael Givskov
- Costern Biofilm Center, Department of International Health, Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark; Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University, Singapore
| | - Tim Tolker-Nielsen
- Costern Biofilm Center, Department of International Health, Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Alan R Hauser
- Department of Microbiology-Immunology, Northwestern University, Chicago, Illinois, United States of America
| | - Joanne N Engel
- Department of Microbiology and Immunology, University of California San Francisco, San Francisco, California, United States of America; Department of Medicine, University of California San Francisco, San Francisco, California, United States of America
| |
Collapse
|