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Brown MA, Jabeen M, Bharj G, Hinks TSC. Non-typeable Haemophilus influenzae airways infection: the next treatable trait in asthma? Eur Respir Rev 2022; 31:220008. [PMID: 36130784 PMCID: PMC9724834 DOI: 10.1183/16000617.0008-2022] [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: 01/14/2022] [Accepted: 07/04/2022] [Indexed: 11/05/2022] Open
Abstract
Asthma is a complex, heterogeneous condition that affects over 350 million people globally. It is characterised by bronchial hyperreactivity and airways inflammation. A subset display marked airway neutrophilia, associated with worse lung function, higher morbidity and poor response to treatment. In these individuals, recent metagenomic studies have identified persistent bacterial infection, particularly with non-encapsulated strains of the Gram-negative bacterium Haemophilus influenzae. Here we review knowledge of non-typeable H. influenzae (NTHi) in the microbiology of asthma, the immune consequences of mucosal NTHi infection, various immune evasion mechanisms, and the clinical implications of NTHi infection for phenotyping and targeted therapies in neutrophilic asthma. Airway neutrophilia is associated with production of neutrophil chemokines and proinflammatory cytokines in the airways, including interleukin (IL)-1β, IL-6, IL-8, IL-12, IL-17A and tumour necrosis factor. NTHi adheres to and invades the lower respiratory tract epithelium, inducing the NLR family pyrin domain containing 3 (NLRP3) and absent in melanoma 2 (AIM2) inflammasomes. NTHi reduces expression of tight-junction proteins, impairing epithelial integrity, and can persist intracellularly. NTHi interacts with rhinoviruses synergistically via upregulation of intracellular cell adhesion molecule 1 and promotion of a neutrophilic environment, to which NTHi is adapted. We highlight the clinical relevance of this emerging pathogen and its relevance for the efficacy of long-term macrolide therapy in airways diseases, we identify important unanswered questions and we propose future directions for research.
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Affiliation(s)
- Mary Ashley Brown
- Respiratory Medicine Unit and National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Experimental Medicine Division, Nuffield Dept of Medicine, University of Oxford, Oxford, UK
| | - Maisha Jabeen
- Respiratory Medicine Unit and National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Experimental Medicine Division, Nuffield Dept of Medicine, University of Oxford, Oxford, UK
| | - Gurpreet Bharj
- Respiratory Medicine Unit and National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Experimental Medicine Division, Nuffield Dept of Medicine, University of Oxford, Oxford, UK
- Mammalian Genetics Unit, MRC Harwell Institute, Oxford, UK
| | - Timothy S C Hinks
- Respiratory Medicine Unit and National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC), Experimental Medicine Division, Nuffield Dept of Medicine, University of Oxford, Oxford, UK
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2
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Kono M, Umar NK, Takeda S, Ohtani M, Murakami D, Sakatani H, Kaneko F, Nanushaj D, Hotomi M. Novel Antimicrobial Treatment Strategy Based on Drug Delivery Systems for Acute Otitis Media. Front Pharmacol 2021; 12:640514. [PMID: 34421583 PMCID: PMC8371970 DOI: 10.3389/fphar.2021.640514] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 07/22/2021] [Indexed: 12/27/2022] Open
Abstract
Despite tremendous success of pneumococcal conjugated vaccine and antimicrobial treatment by amoxicillin, acute otitis media (AOM) still remains as a great medical concern. Failure of antimicrobial treatment includes several factors. The middle ear cavity is surrounded by bone tissue, which makes it difficult to maintain sufficient concentration of antibiotics. Tympanic membrane of AOM patients thickens and actually becomes a barrier for topical therapy. This review discusses novel antimicrobial treatment strategies based on drug delivery systems (DDS) for AOM. To deliver drugs enough to kill the pathogenic bacteria without systemic side effects, the development of new antimicrobial treatment strategy applying innovative drug DDS has been expected. The sustained-release DDS can achieve sufficient time for antimicrobial concentrations to exceed minimum inhibitory concentration (MIC) for time-dependent antibiotics as well as enough maximum concentration for dose-dependent antibiotics to eradicate causative pathogens in the middle ear. The development of trans-tympanic membranes of DDS, such as hydrogels with chemical permeation enhancers (CPEs), is another attractive strategy. Phage is a promising strategy for developing DDS-based therapies. The DDS formulations enable antimicrobial treatment of AOM by a single dose and thus, an attractive future antimicrobial treatment for AOM.
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Affiliation(s)
- Masamitsu Kono
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Nafisa K Umar
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Saori Takeda
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Makiko Ohtani
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Daichi Murakami
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Hideki Sakatani
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Fumie Kaneko
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan.,Department of Otorhinolaryngology, Tokyo Women's Medical University Medical Center East, Tokyo, Japan
| | - Denisa Nanushaj
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Muneki Hotomi
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
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3
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Iuchi H, Ohori J, Kiyama S, Imuta N, Nishi J, Kurono Y, Yamashita M. Effectiveness of antibacterial agents against cell-invading bacteria such as Streptococcus pyogenes and Haemophilus influenzae. BMC Microbiol 2021; 21:148. [PMID: 33990180 PMCID: PMC8122569 DOI: 10.1186/s12866-021-02217-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 05/03/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Recurrent tonsillitis is one of the most common otolaryngological disorders caused by cell-invading bacteria, such as Streptococcus pyogenes (S. pyogenes) and Haemophilus influenzae. The aim of this study was to investigate the effect of antibacterial agents against cell-invading bacteria. METHODS The intracellular invasion of Detroit 562 cells by five strains of nontypeable Haemophilus influenzae (NTHi) and four strains of S. pyogenes was investigated. The antibacterial agents used were garenoxacin (GRNX), clarithromycin (CAM), amoxicillin (AMPC), cefditoren pivoxil (CDTR-PI), and levofloxacin (LVFX). RESULTS Both NTHi and S. pyogenes fully invaded Detroit 562 cells in 6 h and were less sensitive to CAM. GRNX, CAM, and LVFX were effective against bacteria invading the cells, but AMPC and CDTR-PI were not effective. GRNX was the most effective. CONCLUSION GRNX was the most effective agent against bacteria invading cells.
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Affiliation(s)
- Hiroyuki Iuchi
- Department of Otolaryngology, Head and Neck Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan.
| | - Junichiro Ohori
- Department of Otolaryngology, Head and Neck Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan
| | - Satoshi Kiyama
- Department of Otolaryngology, Head and Neck Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan
| | - Naoko Imuta
- Department of Microbiology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan
| | - Junichiro Nishi
- Department of Microbiology, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan
| | - Yuichi Kurono
- Department of Otolaryngology, Head and Neck Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan
| | - Masaru Yamashita
- Department of Otolaryngology, Head and Neck Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, 890-8544, Japan
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4
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Haemophilin-Producing Strains of Haemophilus haemolyticus Protect Respiratory Epithelia from NTHi Colonisation and Internalisation. Pathogens 2021; 10:pathogens10010029. [PMID: 33401487 PMCID: PMC7823694 DOI: 10.3390/pathogens10010029] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 12/28/2020] [Accepted: 12/28/2020] [Indexed: 11/17/2022] Open
Abstract
Nontypeable Haemophilus influenzae (NTHi) is a significant respiratory tract pathogen responsible for infections that collectively pose a substantial health and socioeconomic burden. The clinical course of these infections is largely dictated by NTHi interactions with host respiratory epithelia, and thus, approaches that disrupt colonisation and invasion may have significant therapeutic potential. Survival, successful host–cell interactions, and pathogenesis are reliant on NTHi’s ability to sequester host-derived haem. Previously, we demonstrated the therapeutic potential of exploiting this haem-dependence using a closely related competitor bacterium, Haemophilus haemolyticus (Hh). Hh strains capable of producing the novel haem-binding protein haemophilin (Hpl) possessed potent inhibitory activity by restricting NTHi access to haem in a broth co-culture environment. Here, we extend this work to cell culture models that more closely represent the human respiratory epithelium and show that Hh strains with high levels of hpl expression protect epithelial cell line monolayers against adhesion and invasion by NTHi. Inhibitory activity was dependent on the level of Hpl production, which was stimulated by NTHi challenge and nasopharyngeal cell exposure. Provided these protective benefits translate to in vivo applications, Hpl-producing Hh may have probiotic utility against NTHi infections by inhibiting requisite nasopharyngeal colonisation.
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Kono M, Fukushima K, Kamide Y, Kunimoto M, Matsubara S, Sawada S, Shintani T, Togawa A, Uchizono A, Uno Y, Yamanaka N, Hotomi M. Features predicting treatment failure in pediatric acute otitis media. J Infect Chemother 2020; 27:19-25. [PMID: 32828678 DOI: 10.1016/j.jiac.2020.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/30/2020] [Accepted: 08/03/2020] [Indexed: 11/24/2022]
Abstract
OBJECTIVES To facilitate better antibiotic stewardship, we conducted this clinical trial to identify the prognostic features of treatment failure in pediatric acute otitis media (AOM). STUDY Design: This is a randomized, parallel-group, open-label, comparative clinical trial. SUBJECTS AND METHODS Children with AOM and aged between 1 month and 5 years were enrolled. Patients were randomly assigned to receive either amoxicillin alone (70 mg/kg) for five days, or the same with additional clarithromycin (15 mg/kg) for the initial three days. The clinical course of AOM was evaluated based on tympanic membrane scores. Failure of treatment for AOM was confirmed on day 14. Nasal conditions were also assessed by a clinical scoring system for acute rhinosinusitis. RESULTS Treatment failures occurred in 25 out of 129 (19.4%) children. The ratio of treatment failures by age was significantly higher in children younger than 2 years than in children older than 2 years. The tympanic membrane scores on day 3 (P = 0.0334) and day 5 (P < 0.0001) and acute rhinosinusitis scores on day 5 (P = 0.0004) were higher in failure cases than in cured cases. Multivariate logistic regression analysis indicated significant associations between the treatment failure with tympanic membrane scores and acute rhinosinusitis scores on day 5, and the antimicrobial treatment regimen. CONCLUSIONS Improvement of acute rhinosinusitis and tympanic membrane scores on day five were important predictive features in failure of treatment for pediatric AOM. These results will be useful when discussing the treatment decisions with the patient's parents.
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Affiliation(s)
- Masamitsu Kono
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama-shi, Wakayama 641-8510, Japan
| | - Kunihiro Fukushima
- Department of Dermatology & Otolaryngology, Hayashima Clinic, 1475-2 Hayashima, Hayashima-cho, Tokubo-gun, Okayama, 701-0304, Japan
| | - Yosuke Kamide
- Kamide ENT Clinic, 2433-4 Denbou, Fuji-shi, Shizuoka 417-0061, Japan
| | - Masaru Kunimoto
- Kunimoto ENT Clinic, 5769-7 Tomo Aza Oohara, Numata-cho, Asa Minami-ku, Hiroshima -shi, Hiroshima 731-3161, Japan
| | | | - Shoichi Sawada
- Sawada Eye and Ear Clinic, 1734-5 Fukui-cho, Kochi-shi, Kochi, 780-0965, Japan
| | - Tomoko Shintani
- Tomo ENT Clinic, 1-246 Minami 1-jo Nishi 16-chome, Chuo-ku, Sapporo, Hokkaido 060-8611, Japan
| | - Akihisa Togawa
- Sunsun Clinic, 569-1 Nogawa, Wakayama-shi, Wakayama 640-8481, Japan
| | - Akihiro Uchizono
- Sendai ENT Clinic, 1945-1 Taki-cho, Satsuma Sendai-shi, Kagoshima 895-0211, Japan
| | - Yoshifumi Uno
- Uno ENT Clinic, 3702-4 Kita Tomihara, Okayama-shi, Okayama, 701-1153, Japan
| | - Noboru Yamanaka
- Moriya Keiyu Hospital, 980-1 Tachizawa, Moriya-shi, Ibaraki, 302-0118, Japan
| | - Muneki Hotomi
- Department of Otorhinolaryngology-Head and Neck Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama-shi, Wakayama 641-8510, Japan.
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6
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Lee J, Leichtle A, Zuckerman E, Pak K, Spriggs M, Wasserman SI, Kurabi A. NOD1/NOD2-mediated recognition of non-typeable Haemophilus influenzae activates innate immunity during otitis media. Innate Immun 2019; 25:503-512. [PMID: 31474163 PMCID: PMC6900663 DOI: 10.1177/1753425919872266] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Pathogen recognition following infection in mammals depends mainly on TLRs and
NLRs. Herein, we evaluate the role of NOD1 and NOD2 signaling in the
inflammatory responses of the middle ear (ME) mucosa and leukocytes recruitment
to infection site during otitis media (OM). OM is a common pediatric disease
with prevalent repercussions on hearing health. While many risk factors have
been implicated to OM proneness, immunity and the triggering of inflammation are
central to OM pathology. We observed that many genes encoding members of the NOD
leucine-rich repeat and their downstream adaptor/effector molecules were
strongly regulated during the course of OM. When compared to wild type C57BL/6
mice, NOD1- and NOD2-deficient mice were susceptible to prolonged OM infection
by non-typeable Haemophilus influenza. NOD1-deficient mice
appeared to have reduced macrophage enlistment with a delayed inflammatory
response by neutrophils and prolonged mucosal hyperplasia, whereas NOD2
knockouts exhibited an overall reduction in the number of leukocytes recruited
to the ME, leading to delayed bacterial clearance. Altogether, these data show
that the NODs play a role in the pathogenesis and recovery of OM and reinforce
the importance of innate immune signaling in the protective host response.
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Affiliation(s)
- Jasmine Lee
- Department of Surgery, University of California San Diego, USA
| | - Anke Leichtle
- Department of Surgery, University of California San Diego, USA.,Department of Otolaryngology, University of Lübeck, Germany
| | - Emily Zuckerman
- Department of Surgery, University of California San Diego, USA
| | - Kwang Pak
- Department of Surgery, University of California San Diego, USA.,San Diego Veterans Administration Healthcare System, La Jolla, CA, USA
| | - Meghan Spriggs
- Department of Surgery, University of California San Diego, USA
| | | | - Arwa Kurabi
- Department of Surgery, University of California San Diego, USA.,San Diego Veterans Administration Healthcare System, La Jolla, CA, USA
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7
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Hardison RL, Heimlich DR, Harrison A, Beatty WL, Rains S, Moseley MA, Thompson JW, Justice SS, Mason KM. Transient Nutrient Deprivation Promotes Macropinocytosis-Dependent Intracellular Bacterial Community Development. mSphere 2018; 3:3/5/e00286-18. [PMID: 30209128 PMCID: PMC6135960 DOI: 10.1128/msphere.00286-18] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Nutrient limitation restricts bacterial growth in privileged sites such as the middle ear. Transient heme-iron restriction of nontypeable Haemophilus influenzae (NTHI), the major causative agent of chronic and recurrent otitis media (OM), promotes new and diverse phenotypes that can influence planktonic, biofilm, and intracellular lifestyles of NTHI. However, the bacterial responses to nutrient restriction that impact intracellular fate and survival of NTHI are unknown. In this work, we provide evidence for the role of transient heme-iron restriction in promoting the formation of intracellular bacterial communities (IBCs) of NTHI both in vitro and in vivo in a preclinical model of OM. We show that transient heme-iron restriction of NTHI results in significantly increased invasion and intracellular populations that escape or evade the endolysosomal pathway for increased intracellular survival. In contrast, NTHI continuously exposed to heme-iron traffics through the endolysosomal pathway for degradation. The use of pharmacological inhibitors revealed that prior heme-iron status does not appear to influence NTHI internalization through endocytic pathways. However, inhibition of macropinocytosis altered the intracellular fate of transiently restricted NTHI for degradation in the endolysosomal pathway. Furthermore, prevention of macropinocytosis significantly reduced the number of IBCs in cultured middle ear epithelial cells, providing evidence for the feasibility of this approach to reduce OM persistence. These results reveal that microenvironmental cues can influence the intracellular fate of NTHI, leading to new mechanisms for survival during disease progression.IMPORTANCE Otitis media is the most common bacterial infection in childhood. Current therapies are limited in the prevention of chronic or recurrent otitis media which leads to increased antibiotic exposure and represents a significant socioeconomic burden. In this study, we delineate the effect of nutritional limitation on the intracellular trafficking pathways used by nontypeable Haemophilus influenzae (NTHI). Moreover, transient limitation of heme-iron led to the development of intracellular bacterial communities that are known to contribute to persistence and recurrence in other diseases. New approaches for therapeutic interventions that reduce the production of intracellular bacterial communities and promote trafficking through the endolysosomal pathway were revealed through the use of pharmacological inhibition of macropinocytosis. This work demonstrates the importance of an intracellular niche for NTHI and provides new approaches for intervention for acute, chronic, and recurring episodes of otitis media.
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Affiliation(s)
- Rachael L Hardison
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
- The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Derek R Heimlich
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Alistair Harrison
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Wandy L Beatty
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Sarah Rains
- Duke Proteomics and Metabolomics Core Facility, Duke Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, USA
| | - M Arthur Moseley
- Duke Proteomics and Metabolomics Core Facility, Duke Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, USA
| | - J Will Thompson
- Duke Proteomics and Metabolomics Core Facility, Duke Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, USA
| | - Sheryl S Justice
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
| | - Kevin M Mason
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
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8
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Murphy TF, Kirkham C, Gallo MC, Yang Y, Wilding GE, Pettigrew MM. Immunoglobulin A Protease Variants Facilitate Intracellular Survival in Epithelial Cells By Nontypeable Haemophilus influenzae That Persist in the Human Respiratory Tract in Chronic Obstructive Pulmonary Disease. J Infect Dis 2017; 216:1295-1302. [PMID: 28968876 DOI: 10.1093/infdis/jix471] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Accepted: 09/06/2017] [Indexed: 01/02/2023] Open
Abstract
Background Nontypeable Haemophilus influenzae (NTHi) persists in the airways in chronic obstructive pulmonary disease (COPD). NTHi expresses 4 immunoglobulin (Ig)A protease variants (A1, A2, B1, B2) with distinct cleavage specificities for human IgA1. Little is known about the different roles of IgA protease variants in NTHi infection. Methods Twenty-six NTHi isolates from a 20-year longitudinal study of COPD were analyzed for IgA protease expression, survival in human respiratory epithelial cells, and cleavage of lysosomal-associated membrane protein 1 (LAMP1). Results IgA protease B1 and B2-expressing strains showed greater intracellular survival in host epithelial cells than strains expressing no IgA protease (P < .001) or IgA protease A1 or A2 (P < .001). Strains that lost IgA protease expression showed reduced survival in host cells compared with the same strain that expressed IgA protease B1 (P = .006) or B2 (P = .015). IgA proteases B1 and B2 cleave LAMP1. Passage of strains through host cells selected for expression of IgA proteases B1 and B2 but not A1. Conclusions IgA proteases B1 and B2 cleave LAMP1 and mediate intracellular survival in respiratory epithelial cells. Intracellular persistence of NTHi selects for expression of IgA proteases B1 and B2. The variants of NTHi IgA proteases play distinct roles in pathogenesis of infection.
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Affiliation(s)
- Timothy F Murphy
- Division of Infectious Diseases, Department of Medicine.,Department of Microbiology and Immunology.,Clinical and Translational Research Center, University at Buffalo, the State University of New York
| | - Charmaine Kirkham
- Division of Infectious Diseases, Department of Medicine.,Clinical and Translational Research Center, University at Buffalo, the State University of New York
| | - Mary C Gallo
- Department of Microbiology and Immunology.,Clinical and Translational Research Center, University at Buffalo, the State University of New York
| | | | | | - Melinda M Pettigrew
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, Yale University, New Haven, Connecticut
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9
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Singh NK, Kunde DA, Tristram SG. Inability of Haemophilus haemolyticus to invade respiratory epithelial cells in vitro. J Med Microbiol 2016; 65:1341-1342. [PMID: 27624822 DOI: 10.1099/jmm.0.000349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Affiliation(s)
- Neeraj Kumar Singh
- School of Health Sciences, University of Tasmania, Launceston, Tasmania, Australia
| | - Dale A Kunde
- School of Health Sciences, University of Tasmania, Launceston, Tasmania, Australia
| | - Stephen G Tristram
- School of Health Sciences, University of Tasmania, Launceston, Tasmania, Australia
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10
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Singh NK, Kunde DA, Tristram SG. Effect of epithelial cell type on in vitro invasion of non-typeable Haemophilus influenzae. J Microbiol Methods 2016; 129:66-69. [PMID: 27473508 DOI: 10.1016/j.mimet.2016.07.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 11/28/2022]
Abstract
Non-typeable Haemophilus influenzae (NTHi) have been shown to have variable ability for in vitro invasion with a range of epithelial cells, and increased invasion of BEAS-2B cells has been associated with altered penicillin binding protein3 (PBP3), which is concerning as these strains are increasing worldwide. The aim of the study was to investigate the effect of respiratory cell type and the presence of altered PBP3 on the in vitro invasion of NTHi. A collection of 16 clinical NTHi isolates was established, 7 had normal PBP3, and 9 had altered PBP3 as defined by an N526K substitution. The isolates were tested for invasion of BEAS-2B, NHBE, A549 and NCI-H292 respiratory epithelial cells in vitro using a gentamicin survival assay, with invasion measured as the percentage of intracellular organisms relative to the initial inoculum. The overall median invasion for the 16 NTHi isolates for cell types BEAS-2B, NHBE, A549 and NCI-H292 cells were 3.17, 2.31, 0.11 and 1.52 respectively. The differences were statistically significant for BEAS-2B compared to A549 (P=0.015) and A549 compared to NCI-H292 (P=0.015), and there were also very marked differences in invasion for some individual isolates depending on the cell type used. There was a consistent bias for invasion of isolates with normal versus abnormal PBP3: and this was statistically significant for BEAS-2B (0.07 to 9.90, P=0.031) and A549 cells (0.02 to 1.68, P=0.037). These results show that NTHi invasion of respiratory epithelial cells in vitro is both strain dependant and influenced significantly by the cell line used, and that the association between altered PBP3 and increased invasion is conserved across multiple cell lines.
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Affiliation(s)
- Neeraj Kumar Singh
- School of Health Sciences, University of Tasmania, Launceston, Tasmania, Australia
| | - Dale A Kunde
- School of Health Sciences, University of Tasmania, Launceston, Tasmania, Australia
| | - Stephen G Tristram
- School of Health Sciences, University of Tasmania, Launceston, Tasmania, Australia.
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11
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Ben-Shimol S, Givon-Lavi N, Leibovitz E, Raiz S, Greenberg D, Dagan R. Impact of Widespread Introduction of Pneumococcal Conjugate Vaccines on Pneumococcal and Nonpneumococcal Otitis Media. Clin Infect Dis 2016; 63:611-8. [DOI: 10.1093/cid/ciw347] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 05/17/2016] [Indexed: 11/13/2022] Open
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12
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Kress-Bennett JM, Hiller NL, Eutsey RA, Powell E, Longwell MJ, Hillman T, Blackwell T, Byers B, Mell JC, Post JC, Hu FZ, Ehrlich GD, Janto BA. Identification and Characterization of msf, a Novel Virulence Factor in Haemophilus influenzae. PLoS One 2016; 11:e0149891. [PMID: 26977929 PMCID: PMC4792463 DOI: 10.1371/journal.pone.0149891] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 02/05/2016] [Indexed: 12/11/2022] Open
Abstract
Haemophilus influenzae is an opportunistic pathogen. The emergence of virulent, non-typeable strains (NTHi) emphasizes the importance of developing new interventional targets. We screened the NTHi supragenome for genes encoding surface-exposed proteins suggestive of immune evasion, identifying a large family containing Sel1-like repeats (SLRs). Clustering identified ten SLR-containing gene subfamilies, each with various numbers of SLRs per gene. Individual strains also had varying numbers of SLR-containing genes from one or more of the subfamilies. Statistical genetic analyses of gene possession among 210 NTHi strains typed as either disease or carriage found a significant association between possession of the SlrVA subfamily (which we have termed, macrophage survival factor, msf) and the disease isolates. The PittII strain contains four chromosomally contiguous msf genes. Deleting all four of these genes (msfA1-4) (KO) resulted in a highly significant decrease in phagocytosis and survival in macrophages; which was fully complemented by a single copy of the msfA1 gene. Using the chinchilla model of otitis media and invasive disease, the KO strain displayed a significant decrease in fitness compared to the WT in co-infections; and in single infections, the KO lost its ability to invade the brain. The singly complemented strain showed only a partial ability to compete with the WT suggesting gene dosage is important in vivo. The transcriptional profiles of the KO and WT in planktonic growth were compared using the NTHi supragenome array, which revealed highly significant changes in the expression of operons involved in virulence and anaerobiosis. These findings demonstrate that the msfA1-4 genes are virulence factors for phagocytosis, persistence, and trafficking to non-mucosal sites.
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Affiliation(s)
- Jennifer M. Kress-Bennett
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - N. Luisa Hiller
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Rory A. Eutsey
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
| | - Evan Powell
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
| | - Mark J. Longwell
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
| | - Todd Hillman
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
| | - Tenisha Blackwell
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
| | - Barbara Byers
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
| | - Joshua C. Mell
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- Center for Genomic Sciences, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - J. Christopher Post
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- Department of Otolaryngology, Head and Neck Surgery, Drexel University College of Medicine, Allegheny Campus, Pittsburgh, Pennsylvania, United States of America
| | - Fen Z. Hu
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- Department of Otolaryngology, Head and Neck Surgery, Drexel University College of Medicine, Allegheny Campus, Pittsburgh, Pennsylvania, United States of America
| | - Garth D. Ehrlich
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- Center for Genomic Sciences, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- Department of Otolaryngology, Head and Neck Surgery, Drexel University College of Medicine, Allegheny Campus, Pittsburgh, Pennsylvania, United States of America
| | - Benjamin A. Janto
- Center for Genomic Sciences, Allegheny Singer Research Institute, Allegheny General Hospital, Pittsburgh, Pennsylvania, United States of America
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- Center for Genomic Sciences, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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Ikeda M, Enomoto N, Hashimoto D, Fujisawa T, Inui N, Nakamura Y, Suda T, Nagata T. Nontypeable Haemophilus influenzae exploits the interaction between protein-E and vitronectin for the adherence and invasion to bronchial epithelial cells. BMC Microbiol 2015; 15:263. [PMID: 26572616 PMCID: PMC4647820 DOI: 10.1186/s12866-015-0600-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Accepted: 11/06/2015] [Indexed: 12/05/2022] Open
Abstract
Background Nontypeable Haemophilus influenzae (NTHi) is one of the most common Gram-negative pathogens in otitis media and exacerbation of chronic obstructive pulmonary disease. NTHi has been reported to invade bronchial epithelial cells. This penetration enables NTHi to evade the host immune system and antibiotics, and it seems to be related to the intractable features of these diseases. However, the precise mechanism of the invasion has been unknown. We hypothesized that protein-E, an outer membrane protein of NTHi, plays a role in this penetration into bronchial epithelial cells. Results We utilized two NTHi strains. NTHi efficiently attached to plate-bound vitronectin (254–309 / field at 1,000× magnification) and this attachment was blocked by pretreatment with protein-E peptide (PE84–108). The blockade of adhesion was dependent on the concentration of PE84–108. NTHi strains invaded bronchial epithelial cells and the intracellular bacteria were localized in early endosomes. Furthermore, intracellular invasion of NTHi was also blocked by PE84–108, but not by Arg-Gly-Asp (RGD) peptide. Pretreatment with PE84–108 significantly prevented cells from being invaded by both NTHi strains, which was confirmed by fluorescent microscope observation. In addition, pretreatment with PE84–108 significantly reduced percentages of CFU after gentamicin treatment of cells per input CFU. Conclusions These results suggest that NTHi does not directly bind to the cell surface, but binds to host vitronectin that is bound to the cell surface, via bacterial protein-E. Bacterial protein-E and host vitronectin play a role in the attachment to bronchial epithelial cells and is also involved in the subsequent intracellular invasion of NTHi. A novel vaccine or treatment strategy targeting the protein-E-vitronectin axis may prevent respiratory intracellular infection of NTHi and may lead to better clinical outcomes. Electronic supplementary material The online version of this article (doi:10.1186/s12866-015-0600-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Masaki Ikeda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan.
| | - Noriyuki Enomoto
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan.
| | - Dai Hashimoto
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan.
| | - Tomoyuki Fujisawa
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan.
| | - Naoki Inui
- Department of Clinical Pharmacology and Therapeutics, Hamamatsu University School of Medicine, Hamamatsu, Japan.
| | - Yutaro Nakamura
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan.
| | - Takafumi Suda
- Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Japan.
| | - Toshi Nagata
- Department of Health Science, Hamamatsu University School of Medicine, Hamamatsu, Japan.
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Olszewska-Sosińska O, Zielnik-Jurkiewicz B, Stępińska M, Antos-Bielska M, Lau-Dworak M, Kozłowska K, Trafny EA. Persistence of non-typeable Haemophilus Influenzae in the pharynx of children with adenotonsillar hypertrophy after treatment with azithromycin. Pathog Dis 2015; 74:ftv106. [PMID: 26546328 DOI: 10.1093/femspd/ftv106] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/30/2015] [Indexed: 11/13/2022] Open
Abstract
This study was performed in children with adenotonsillar hypertrophy to evaluate the effect of azithromycin (AZT) on the presence of NTHi in monocyte/macrophages (CD14(+) cells) of adenoids/tonsils and the persistence of NTHi after adenotonsillectomy. A total of 36 pediatric patients participated in the study: 20 children were treated with AZT before adenotonsillectomy, and 16 children did not receive the antibiotic prior to surgery. NTHi were identified by culture and PCR in swabs and tissue samples. NTHi was detected in the lysates of CD14(+) cells by fluorescence in situ hybridization (FISH) and by culture. The molecular typing was used to cluster NTHi isolates from each child. The intracellular NTHi was found in 10 (62.5%) untreated patients and was identified in three (15%) azithromycin-treated patients (P = 0.003). The proportion of the persistent NTHi strains was similar in both groups. AZT treatment followed by adenotonsillectomy did not completely eliminate NTHi from pharynges; however, it significantly reduced the risk of carriage of Haemophilus influenzae inside the CD14(+) cells.
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Affiliation(s)
- O Olszewska-Sosińska
- Department of Otolaryngology Children's Hospital, Niekłańska 4/24, 03-924 Warsaw, Poland
| | - B Zielnik-Jurkiewicz
- Department of Otolaryngology Children's Hospital, Niekłańska 4/24, 03-924 Warsaw, Poland
| | - M Stępińska
- Department of Microbiology, Military Institute of Hygiene and Epidemiology, Kozielska 4, 01-163 Warsaw, Poland
| | - M Antos-Bielska
- Department of Microbiology, Military Institute of Hygiene and Epidemiology, Kozielska 4, 01-163 Warsaw, Poland
| | - M Lau-Dworak
- Department of Laboratory Diagnostics, Children's Hospital, Niekłańska 4/24, 03-924 Warsaw, Poland
| | - K Kozłowska
- Department of Microbiology, Military Institute of Hygiene and Epidemiology, Kozielska 4, 01-163 Warsaw, Poland
| | - E A Trafny
- Department of Microbiology, Military Institute of Hygiene and Epidemiology, Kozielska 4, 01-163 Warsaw, Poland
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Haemophilus influenzae triggers autophagy in HEp-2 cells. Arch Microbiol 2015; 198:199-204. [PMID: 26537814 DOI: 10.1007/s00203-015-1167-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 09/24/2015] [Accepted: 10/27/2015] [Indexed: 10/22/2022]
Abstract
The MAP-LC3 system regulates the intracellular formation of autophagy-associated vacuoles. These vacuoles contain the LC3 protein; thus it has been utilized as a marker to identify autophagosomes. The aim of our study was to investigate whether Haemophilus influenzae strains and their supernatants could activate autophagy in human larynx carcinoma cell line (HEp-2). We demonstrate that higher expression of the LC3B-II protein was induced, particularly by nontypeable Haemophilus influenzae (NTHi) 49766 and by supernatants, containing <50 kDa proteins, of both strains. Ultrastructural studies demonstrate vacuoles with a double membrane and/or membrane material inside, showing similar features to those of autophagic vacuoles. Together, our findings demonstrate that H. influenzae strains and their supernatants trigger an autophagic process.
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16
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Goyal M, Singh M, Ray P, Srinivasan R, Chakraborti A. Cellular interaction of nontypeable Haemophilus influenzae triggers cytotoxicity of infected type II alveolar cells via apoptosis. Pathog Dis 2015; 73:1-12. [PMID: 25227327 DOI: 10.1111/2049-632x.12215] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Nontypeable Haemophilus influenzae (NTHi) is an important cause of lower respiratory tract infections, resulting in exacerbations of chronic obstructive pulmonary disease (COPD). Despite its pathogenic potential, little is known regarding the role of intracellular NTHi in pathogenesis of pulmonary infection. Kinetics of NTHi internalization was studied using gentamicin protection assays. NTHi strains isolated from COPD patients efficiently adhere to and invade type II alveolar (A549) cells. During early stages, that is, 6 h postinfection, we noted a substantial increase in NTHi invasion with no evidence of intracellular replication. Electron microscopy revealed that the majority of internalized NTHi resided within membrane bound acidic endocytic vacuoles. However, at later stages, that is, 8 h postinfection, significant reduction in viable intracellular NTHi was observed and vacuoles were found to be empty with NTHi escape into the cytosol. By 12 h, cytopathic changes of cells were evident with massive vacuolization of cytoplasm, intense chromatin condensation, and intact plasma membrane. Furthermore, analysis of apoptotic markers confirmed that infected A549 cells underwent apoptosis at later stages. In addition, inhibition of internalization of NTHi by cytochalasin D prevented apoptosis of cells. Collectively, these findings suggest that internalization of NTHi and its escape from vacuolar compartments triggers cytotoxicity of alveolar cells via apoptosis during the infection process.
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Affiliation(s)
- Manu Goyal
- Department of Experimental Medicine and Biotechnology, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Meenu Singh
- Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Pallab Ray
- Department of Medical Microbiology, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Radhika Srinivasan
- Department of Cytology and Gynaecological Pathology, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Anuradha Chakraborti
- Department of Experimental Medicine and Biotechnology, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
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Relationship between azithromycin susceptibility and administration efficacy for nontypeable Haemophilus influenzae respiratory infection. Antimicrob Agents Chemother 2015; 59:2700-12. [PMID: 25712355 DOI: 10.1128/aac.04447-14] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 02/14/2015] [Indexed: 12/21/2022] Open
Abstract
Nontypeable Haemophilus influenzae (NTHI) is an opportunistic pathogen that is an important cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). COPD is an inflammatory disease of the airways, and exacerbations are acute inflammatory events superimposed on this background of chronic inflammation. Azithromycin (AZM) is a macrolide antibiotic with antibacterial and anti-inflammatory properties and a clinically proven potential for AECOPD prevention and management. Relationships between AZM efficacy and resistance by NTHI and between bactericidal and immunomodulatory effects on NTHI respiratory infection have not been addressed. In this study, we employed two pathogenic NTHI strains with different AZM susceptibilities (NTHI 375 [AZM susceptible] and NTHI 353 [AZM resistant]) to evaluate the prophylactic and therapeutic effects of AZM on the NTHI-host interplay. At the cellular level, AZM was bactericidal toward intracellular NTHI inside alveolar and bronchial epithelia and alveolar macrophages, and it enhanced NTHI phagocytosis by the latter cell type. These effects correlated with the strain MIC of AZM and the antibiotic dose. Additionally, the effect of AZM on NTHI infection was assessed in a mouse model of pulmonary infection. AZM showed both preventive and therapeutic efficacies by lowering NTHI 375 bacterial counts in lungs and bronchoalveolar lavage fluid (BALF) and by reducing histopathological inflammatory lesions in the upper and lower airways of mice. Conversely, AZM did not reduce bacterial loads in animals infected with NTHI 353, in which case a milder anti-inflammatory effect was also observed. Together, the results of this work link the bactericidal and anti-inflammatory effects of AZM and frame the efficacy of this antibiotic against NTHI respiratory infection.
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18
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Sugita G, Hotomi M, Sugita R, Kono M, Togawa A, Yamauchi K, Funaki T, Yamanaka N. Genetic characteristics of Haemophilus influenzae and Streptococcus pneumoniae isolated from children with conjunctivitis-otitis media syndrome. J Infect Chemother 2014; 20:493-7. [PMID: 24953451 DOI: 10.1016/j.jiac.2014.04.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 04/20/2014] [Accepted: 04/24/2014] [Indexed: 10/25/2022]
Abstract
Acute conjunctivitis is the most common ocular disorders among children and frequently concomitant with acute otitis media (AOM) as conjunctivitis-otitis syndrome. In this study, we evaluated prevalence of causative pathogens and PCR-based genotypes of Haemophilus influenzae and Streptococcus pneumoniae among children with conjunctivitis-otitis media syndrome. Nontypeable H. influenzae (NTHi) is identified most often at 61.8% in conjunctiva exudates followed by S. pneumoniae at 28.2% and Moraxella catarrhalis at 19.1%. Genetic β-lactamase nonproducing ampicillin resistant (gBLNAR) strains of NTHi and genetic penicillin resistant S. pneumoniae (gPRSP) were identified at 72.1% and at 74.2% among conjunctiva isolates by polymerase chain reaction (PCR), respectively. Pneumococcal strains having either ermB or mefE genes were identified at 93.5% among conjunctiva isolates. The restriction fragment of patterns of 89.7% pairs of H. influenzae isolates and 100% pairs of pneumococcal isolates from conjunctiva exudates, middle ear fluids (MEFs) and nasopharyngeal swabs were identical. In contrast to the previous reports, most prevalent strains from conjunctivitis-otitis media syndrome was BLNAR H. influenzae in this study. The causative pathogen responsible for acute conjunctivitis will be originated from the nasopharynx. In the absence of MEFs one can possibly rely on the nasopharyngeal culture to guide an appropriate treatment.
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Affiliation(s)
- Gen Sugita
- Department of Otolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Muneki Hotomi
- Department of Otolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan.
| | | | - Masamitsu Kono
- Department of Otolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Akihisa Togawa
- Department of Otolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Kazuma Yamauchi
- Department of Otolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
| | - Toshinari Funaki
- Department of Ophthalmology, Juntendo University School of Medicine, Tokyo, Japan
| | - Noboru Yamanaka
- Department of Otolaryngology-Head and Neck Surgery, Wakayama Medical University, Wakayama, Japan
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19
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Trafny EA, Olszewska-Sosińska O, Antos-Bielska M, Kozłowska K, Stępińska M, Lau-Dworak M, Zielnik-Jurkiewicz B. Carriage of antibiotic-resistant Haemophilus influenzae strains in children undergoing adenotonsillectomy. Int J Med Microbiol 2014; 304:554-64. [PMID: 24767868 DOI: 10.1016/j.ijmm.2014.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 02/17/2014] [Accepted: 03/24/2014] [Indexed: 12/31/2022] Open
Abstract
Haemophilus influenzae is one of the major pathogenic bacteria in upper respiratory tract of children. In this study, the presence of various H. influenzae genotypes were followed-up for at least 13 weeks, starting from one week before surgery. Forty-one children with chronic adenoid hypertrophy were prospectively enrolled to the study. The consecutive swabs of adenoid and tonsils, two before adenotonsillectomy and two after the surgery together with homogenates of adenotonsillar tissues and lysates of the CD14(+) cells fraction were acquired from 34 children undergoing adenotonsillectomy. Up to ten isolates from each patient at each collection period were genotyped using a PFGE method and their capsular type and antibiotic susceptibility was determined. Of the 1001 isolates examined, we identified 325 isolates grouped into 16 persistent genotypes, which colonized throats for more than seven weeks and were not eliminated by the surgery. The other 506 isolates grouped into 48 transient genotypes that had been eliminated by the surgery. The resistance to ampicillin were found in 23.8% of the transient strains, and 4.7% of the newly acquired strains following the surgical intervention. In contrast, none of the persistent strains were resistant to ampicillin; however, these strains showed apparently higher level of resistance to co-trimoxazole when compared to transient strains. The transient and persistent strains did not significantly differ in bacterial viability in the biofilms formed in vitro. Some of the strains were identified in two or three different patients and were considered as the strains circulating in the region between 2010 and 2012.
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Affiliation(s)
- Elżbieta A Trafny
- Department of Microbiology, Military Institute of Hygiene and Epidemiology, Kozielska 4, 01-163 Warsaw, Poland.
| | | | - Małgorzata Antos-Bielska
- Department of Microbiology, Military Institute of Hygiene and Epidemiology, Kozielska 4, 01-163 Warsaw, Poland
| | - Krystyna Kozłowska
- Department of Microbiology, Military Institute of Hygiene and Epidemiology, Kozielska 4, 01-163 Warsaw, Poland
| | - Małgorzata Stępińska
- Department of Microbiology, Military Institute of Hygiene and Epidemiology, Kozielska 4, 01-163 Warsaw, Poland
| | - Magdalena Lau-Dworak
- Department of Laboratory Diagnostics, Children's Hospital, Niekłańska 4/24, 03-924 Warsaw, Poland
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NOD2/RICK-dependent β-defensin 2 regulation is protective for nontypeable Haemophilus influenzae-induced middle ear infection. PLoS One 2014; 9:e90933. [PMID: 24625812 PMCID: PMC3953203 DOI: 10.1371/journal.pone.0090933] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 02/06/2014] [Indexed: 12/30/2022] Open
Abstract
Middle ear infection, otitis media (OM), is clinically important due to the high incidence in children and its impact on the development of language and motor coordination. Previously, we have demonstrated that the human middle ear epithelial cells up-regulate β-defensin 2, a model innate immune molecule, in response to nontypeable Haemophilus influenzae (NTHi), the most common OM pathogen, via TLR2 signaling. NTHi does internalize into the epithelial cells, but its intracellular trafficking and host responses to the internalized NTHi are poorly understood. Here we aimed to determine a role of cytoplasmic pathogen recognition receptors in NTHi-induced β-defensin 2 regulation and NTHi clearance from the middle ear. Notably, we observed that the internalized NTHi is able to exist freely in the cytoplasm of the human epithelial cells after rupturing the surrounding membrane. The human middle ear epithelial cells inhibited NTHi-induced β-defensin 2 production by NOD2 silencing but augmented it by NOD2 over-expression. NTHi-induced β-defensin 2 up-regulation was attenuated by cytochalasin D, an inhibitor of actin polymerization and was enhanced by α-hemolysin, a pore-forming toxin. NOD2 silencing was found to block α-hemolysin-mediated enhancement of NTHi-induced β-defensin 2 up-regulation. NOD2 deficiency appeared to reduce inflammatory reactions in response to intratympanic inoculation of NTHi and inhibit NTHi clearance from the middle ear. Taken together, our findings suggest that a cytoplasmic release of internalized NTHi is involved in the pathogenesis of NTHi infections, and NOD2-mediated β-defensin 2 regulation contributes to the protection against NTHi-induced otitis media.
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Internalization and trafficking of nontypeable Haemophilus influenzae in human respiratory epithelial cells and roles of IgA1 proteases for optimal invasion and persistence. Infect Immun 2013; 82:433-44. [PMID: 24218477 DOI: 10.1128/iai.00864-13] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nontypeable Haemophilus influenzae (NTHI) is a leading cause of opportunistic infections of the respiratory tract in children and adults. Although considered an extracellular pathogen, NTHI has been observed repeatedly within and between cells of the human respiratory tract, and these observations have been correlated to symptomatic infection. These findings are intriguing in light of the knowledge that NTHI persists in the respiratory tract despite antibiotic therapy and the development of bactericidal antibodies. We hypothesized that intracellular NTHI avoids, escapes, or neutralizes the endolysosomal pathway and persists within human respiratory epithelial cells and that human IgA1 proteases are required for optimal internalization and persistence of NTHI. Virtually all strains encode a human IgA1 protease gene, igaA, and we previously characterized a novel human IgA1 protease gene, igaB, that is associated with disease-causing strains and is homologous to the IgA1 protease that is unique to pathogenic Neisseria spp. Here, we show that NTHI invades human bronchial epithelial cells in vitro in a lipid raft-independent manner, is subsequently trafficked via the endolysosomal pathway, and is killed in lysosomes after variable durations of persistence. IgaA is required for optimal invasion. IgaB appears to play little or no role in adherence or invasion but is required for optimal intracellular persistence of NTHI. IgaB cleaves lysosome-associated membrane protein 1 (LAMP1) at pHs characteristic of the plasma membrane, early endosome, late endosome, and lysosome. However, neither IgA1 protease inhibits acidification of intracellular vesicles containing NTHI. NTHI IgA1 proteases play important but different roles in NTHI invasion and trafficking in respiratory epithelial cells.
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Improvement rate of acute otitis media caused by Haemophilus influenzae at 1 week is significantly associated with time to recovery. J Clin Microbiol 2013; 51:3542-6. [PMID: 23966504 DOI: 10.1128/jcm.01108-13] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Acute otitis media (AOM) is the most common upper respiratory tract infection in childhood. Children with AOM were enrolled at Tohoku Rosai Hospital between July 2006 and June 2011 if their middle ear fluid cultures after tympanocentesis yielded only Haemophilus influenzae. The susceptibilities of the isolates to ampicillin were determined, and microtiter biofilm assays and invasion assays using BEAS-2B cells were performed. The association between these bacterial characteristics and clinical relapses of AOM and treatment failures was evaluated. Seventy-four children (39 boys and 35 girls) with a median age of 1 year (interquartile range [IQR], 0.25 to 2 years) were enrolled. Among 74 H. influenzae isolates, 37 showed intermediate resistance or resistance to ampicillin (MIC, ≥ 2 μg/ml). In the microtiter biofilm assay, the median optical density at 600 nm (OD600) was 0.68 (IQR, 0.24 to 1.02), and 70 isolates formed biofilms. The median invasion rate was 15% (IQR, 0 to 10%), and 46 isolates invaded BEAS-2B cells. Relapses and treatment failures occurred in 19 and 6 children, respectively. There was no significant difference in the invasion rates between patients with and those without relapses or treatment failures. Also, there was no significant association between biofilm formation and relapse or treatment failure. The improvements in the severity scores after 1 week were significantly associated with the recovery time (P < 0.0001). We did not identify any significant association between relapse or treatment failure and bacterial factors. AOM has a multifactorial etiology, and this may explain why we could not find a significant association. An improvement in the severity score after 1 week of treatment may be a useful predictor of the outcome of AOM.
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Identification of Intracellular Bacteria in Adenoid and Tonsil Tissue Specimens: The Efficiency of Culture Versus Fluorescent In Situ Hybridization (FISH). Curr Microbiol 2013; 68:21-9. [DOI: 10.1007/s00284-013-0436-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 07/26/2013] [Indexed: 01/10/2023]
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Cayé-Thomasen P, Hermansson A, Bakaletz L, Hellstrøm S, Kanzaki S, Kerschner J, Lim D, Lin J, Mason K, Spratley J. Panel 3: Recent advances in anatomy, pathology, and cell biology in relation to otitis media pathogenesis. Otolaryngol Head Neck Surg 2013; 148:E37-51. [PMID: 23536531 DOI: 10.1177/0194599813476257] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Accepted: 01/08/2012] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND OBJECTIVES The pathogenesis of otitis media (OM) involves a number of factors related to the anatomy, pathology, and cell biology of the middle ear, the mastoid, the Eustachian tube, and the nasopharynx. Although some issues of pathogenesis are fairly well established, others are only marginally indicated by current knowledge, and yet others remain undisclosed. The objective of this article is to provide a state-of-the-art review on recent scientific achievements in the pathogenesis of OM, as related to anatomy, pathology, and cell biology. DATA SOURCES PubMed, Ovid Medline, and Cochrane Library. REVIEW METHODS Articles published on the pathogenesis of OM and the anatomy, pathology, and cell biology of the middle ear, the mastoid, the Eustachian tube, and the nasopharynx between January 2007 and June 2011 were identified. Among almost 1900 abstracts, the authors selected 130 articles for full article review and inclusion in this report. RESULTS New knowledge on a number of issues emerged, including cell-specific expression and function of fluid transportation and innate immune system molecules, mucous cell metaplasia, mucin expression, bacterial adherence, and epithelial internalization, as well as the occurrence, composition, dynamics, and potential role of bacterial biofilm. In addition, the potential role of gastroesophageal reflux disease and cigarette smoke exposure has been explored further. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE Over the past 4 years, considerable scientific progress has been made on the pathogenesis of OM, as related to issues of anatomy, pathology, and cell biology. Based on these new achievements and a sustained lack of essential knowledge, suggestions for future research are outlined.
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Affiliation(s)
- Per Cayé-Thomasen
- Department of Oto-rhino-laryngology, Head and Neck Surgery, University Hospital of Copenhagen, Copenhagen, Denmark.
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Chang AB, Grimwood K, Wilson AC, van Asperen PP, Byrnes CA, O’Grady KAF, Sloots TP, Robertson CF, Torzillo PJ, McCallum GB, Masters IB, Buntain HM, Mackay IM, Ungerer J, Tuppin J, Morris PS. Bronchiectasis exacerbation study on azithromycin and amoxycillin-clavulanate for respiratory exacerbations in children (BEST-2): study protocol for a randomized controlled trial. Trials 2013; 14:53. [PMID: 23421781 PMCID: PMC3586343 DOI: 10.1186/1745-6215-14-53] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 01/22/2013] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Bronchiectasis unrelated to cystic fibrosis (CF) is being increasingly recognized in children and adults globally, both in resource-poor and in affluent countries. However, high-quality evidence to inform management is scarce. Oral amoxycillin-clavulanate is often the first antibiotic chosen for non-severe respiratory exacerbations, because of the antibiotic-susceptibility patterns detected in the respiratory pathogens commonly associated with bronchiectasis. Azithromycin has a prolonged half-life, and with its unique anti-bacterial, immunomodulatory, and anti-inflammatory properties, presents an attractive alternative. Our proposed study will test the hypothesis that oral azithromycin is non-inferior (within a 20% margin) to amoxycillin-clavulanate at achieving resolution of non-severe respiratory exacerbations by day 21 of treatment in children with non-CF bronchiectasis. METHODS This will be a multicenter, randomized, double-blind, double-dummy, placebo-controlled, parallel group trial involving six Australian and New Zealand centers. In total, 170 eligible children will be stratified by site and bronchiectasis etiology, and randomized (allocation concealed) to receive: 1) azithromycin (5 mg/kg daily) with placebo amoxycillin-clavulanate or 2) amoxycillin-clavulanate (22.5 mg/kg twice daily) with placebo azithromycin for 21 days as treatment for non-severe respiratory exacerbations. Clinical data and a parent-proxy cough-specific quality of life (PC-QOL) score will be obtained at baseline, at the start and resolution of exacerbations, and on day 21. In most children, blood and deep-nasal swabs will also be collected at the same time points. The primary outcome is the proportion of children whose exacerbations have resolved at day 21. The main secondary outcome is the PC-QOL score. Other outcomes are: time to next exacerbation; requirement for hospitalization; duration of exacerbation, and spirometry data. Descriptive viral and bacteriological data from nasal samples and blood inflammatory markers will be reported where available. DISCUSSION Currently, there are no published randomized controlled trials (RCT) to underpin effective, evidence-based management of acute respiratory exacerbations in children with non-CF bronchiectasis. To help address this information gap, we are conducting two RCTs. The first (bronchiectasis exacerbation study; BEST-1) evaluates the efficacy of azithromycin and amoxycillin-clavulanate compared with placebo, and the second RCT (BEST-2), described here, is designed to determine if azithromycin is non-inferior to amoxycillin-clavulanate in achieving symptom resolution by day 21 of treatment in children with acute respiratory exacerbations. TRIAL REGISTRATION Australia and New Zealand Clinical Trials Register (ANZCTR) number http://ACTRN12612000010897. http://www.anzctr.org.au/trial_view.aspx?id=347879.
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Affiliation(s)
- Anne B Chang
- Child Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
- Queensland Children’s Respiratory Centre, Royal Children’s Hospital, Brisbane, QLD, Australia
- Queensland Children’s Medical Research Institute, Brisbane, QLD, Australia
| | - Keith Grimwood
- Queensland Children’s Medical Research Institute, Brisbane, QLD, Australia
- Queensland Paediatric Infectious Diseases Laboratory, Royal Children’s Hospital, Brisbane, QLD, Australia
| | - Andrew C Wilson
- Department of Respiratory Medicine, Princess Margaret Hospital, Perth, Australia
| | - Peter P van Asperen
- Department of Respiratory Medicine, The Children’s Hospital at Westmead and Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - Catherine A Byrnes
- Department of Paediatrics, University of Auckland and Starship Children’s Hospital, Auckland, New Zealand
| | | | - Theo P Sloots
- Queensland Children’s Medical Research Institute, Brisbane, QLD, Australia
- Queensland Paediatric Infectious Diseases Laboratory, Royal Children’s Hospital, Brisbane, QLD, Australia
| | - Colin F Robertson
- Department of Respiratory Medicine, Royal Children’s Hospital, Murdoch Children’s Research Institute, University of Melbourne, Melbourne, VIC, Australia
| | | | - Gabrielle B McCallum
- Child Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
| | - Ian B Masters
- Queensland Children’s Respiratory Centre, Royal Children’s Hospital, Brisbane, QLD, Australia
- Queensland Children’s Medical Research Institute, Brisbane, QLD, Australia
| | - Helen M Buntain
- Queensland Children’s Respiratory Centre, Royal Children’s Hospital, Brisbane, QLD, Australia
- Queensland Children’s Medical Research Institute, Brisbane, QLD, Australia
| | - Ian M Mackay
- Queensland Children’s Medical Research Institute, Brisbane, QLD, Australia
- Queensland Paediatric Infectious Diseases Laboratory, Royal Children’s Hospital, Brisbane, QLD, Australia
| | - Jacobus Ungerer
- Department Chemical Pathology, Queensland Pathology, Royal Brisbane Hospital, Brisbane, Australia
| | - Joanne Tuppin
- Queensland Children’s Respiratory Centre, Royal Children’s Hospital, Brisbane, QLD, Australia
- Queensland Children’s Medical Research Institute, Brisbane, QLD, Australia
| | - Peter S Morris
- Child Health Division, Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
- Department of Paediatrics, Royal Darwin Hospital, Darwin, NT, Australia
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26
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Clementi CF, Murphy TF. Non-typeable Haemophilus influenzae invasion and persistence in the human respiratory tract. Front Cell Infect Microbiol 2011; 1:1. [PMID: 22919570 PMCID: PMC3417339 DOI: 10.3389/fcimb.2011.00001] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 10/04/2011] [Indexed: 12/21/2022] Open
Abstract
Non-typeable Haemophilus influenzae (NTHI) is an opportunistic bacterial pathogen of the human respiratory tract and is a leading cause of respiratory infections in children and adults. NTHI is considered to be an extracellular pathogen, but has consistently been observed within and between human respiratory epithelial cells and macrophages, in vitro and ex vivo. Until recently, few studies have examined the internalization, trafficking, and fate of NTHI in host cells. It is important to clarify this interaction because of a possible correlation between intracellular NTHI and symptomatic infection, and because NTHI infections frequently persist and recur despite antibiotic therapy and the development of bactericidal antibodies, suggesting a possible intracellular state or reservoir for NTHI. How does NTHI enter host cells? Can NTHI survive intracellularly and, if so, for how long? Strides have been made in the identification of host receptors, signaling, endocytosis, and trafficking pathways involved in the entry and persistence of NTHI in the respiratory tract.
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Affiliation(s)
- Cara F Clementi
- Department of Microbiology and Immunology, University at Buffalo, State University of New York Buffalo, NY, USA
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Thornton RB, Rigby PJ, Wiertsema SP, Filion P, Langlands J, Coates HL, Vijayasekaran S, Keil AD, Richmond PC. Multi-species bacterial biofilm and intracellular infection in otitis media. BMC Pediatr 2011; 11:94. [PMID: 22018357 PMCID: PMC3224757 DOI: 10.1186/1471-2431-11-94] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Accepted: 10/24/2011] [Indexed: 12/13/2022] Open
Abstract
Background Bacteria which are metabolically active yet unable to be cultured and eradicated by antibiotic treatment are present in the middle ear effusion of children with chronic otitis media with effusion (COME) and recurrent acute otitis media (rAOM). These observations are suggestive of biofilm presence or intracellular sequestration of bacteria and may play a role in OM pathogenesis. The aim of this project is to provide evidence for the presence of otopathogenic bacteria intracellularly or within biofilm in the middle ear mucosa of children with COME or rAOM. Methods Middle ear mucosal biopsies from 20 children with COME or rAOM were examined for otopathogenic bacteria (either in biofilm or located intracellularly) using transmission electron microscopy (TEM) or species specific fluorescent in situ hybridisation (FISH) and confocal laser scanning microscopy (CLSM). One healthy control biopsy from a child undergoing cochlear implant surgery was also examined. Results No bacteria were observed in the healthy control sample. In 2 of the 3 biopsies imaged using TEM, bacteria were observed in mucus containing vacuoles within epithelial cells. Bacterial species within these could not be identified and biofilm was not observed. Using FISH with CLSM, bacteria were seen in 15 of the 17 otitis media mucosal specimens. In this group, 11 (65%) of the 17 middle ear mucosal biopsies showed evidence of bacterial biofilm and 12 demonstrated intracellular bacteria. 52% of biopsies were positive for both biofilm and intracellular bacteria. At least one otopathogen was identified in 13 of the 15 samples where bacteria were present. No differences were observed between biopsies from children with COME and those with rAOM. Conclusion Using FISH and CLSM, bacterial biofilm and intracellular infection with known otopathogens are demonstrated on/in the middle ear mucosa of children with COME and/or rAOM. While their role in disease pathogenesis remains to be determined, this previously undescribed infection pattern may help explain the ineffectiveness of current treatment strategies at preventing or resolving COME or rAOM.
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Affiliation(s)
- Ruth B Thornton
- School of Paediatrics and Child Health, The University of Western Australia, Perth, Western Australia, Australia.
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Ren D, Daines DA. Use of the EpiAirway model for characterizing long-term host-pathogen interactions. J Vis Exp 2011:e3261. [PMID: 21912369 DOI: 10.3791/3261] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Nontypeable Haemophilus influenzae (NTHi) are human-adapted Gram-negative bacteria that can cause recurrent and chronic infections of the respiratory mucosa (1; 2). To study the mechanisms by which these organisms survive on and inside respiratory tissues, a model in which successful long-term co-culture of bacteria and human cells can be performed is required. We use primary human respiratory epithelial tissues raised to the air-liquid interface, the EpiAirway model (MatTek, Ashland, MA). These are non-immortalized, well-differentiated, 3-dimensional tissues that contain tight junctions, ciliated and nonciliated cells, goblet cells that produce mucin, and retain the ability to produce cytokines in response to infection. This biologically relevant in vitro model of the human upper airway can be used in a number of ways; the overall goal of this method is to perform long-term co-culture of EpiAirway tissues with NTHi and quantitate cell-associated and internalized bacteria over time. As well, mucin production and the cytokine profile of the infected co-cultures can be determined. This approach improves upon existing methods in that many current protocols use submerged monolayer or Transwell cultures of human cells, which are not capable of supporting bacterial infections over extended periods(3). For example, if an organism can replicate in the overlying media, this can result in unacceptable levels of cytotoxicity and loss of host cells, arresting the experiment. The EpiAirway model allows characterization of long-term host-pathogen interactions. Further, since the source for the EpiAirway is normal human tracheo-bronchial cells rather than an immortalized line, each is an excellent representation of actual human upper respiratory tract tissue, both in structure and in function(4). For this method, the EpiAirway tissues are weaned off of anti-microbial and anti-fungal compounds for 2 days prior to delivery, and all procedures are performed under antibiotic-free conditions. This necessitates special considerations, since both bacteria and primary human tissues are used in the same biosafety cabinet, and are co-cultured for extended periods.
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Affiliation(s)
- Dabin Ren
- Division of Basic Medical Sciences, Mercer University School of Medicine
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Frandoloso R, Martínez-Martínez S, Gutiérrez-Martín CB, Rodríguez-Ferri EF. Haemophilus parasuis serovar 5 Nagasaki strain adheres and invades PK-15 cells. Vet Microbiol 2011; 154:347-52. [PMID: 21839589 DOI: 10.1016/j.vetmic.2011.07.022] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 07/13/2011] [Accepted: 07/19/2011] [Indexed: 10/17/2022]
Abstract
Haemophilus parasuis is the agent responsible for causing Glässer's disease, which is characterized by fibrinous polyserositis, polyarthritis and meningitis in pigs. The purpose of this study was to investigate the in vitro ability of two H. parasuis serovars of different virulence (serovar 5, Nagasaki strain, highly virulent, belonging to serovar 5, and SW114 strain, nonvirulent, belonging to serovar 3) to adhere to and invade porcine kidney epithelial cells (PK-15 line). Nagasaki strain was able to attach at high levels from 60 to 180 min of incubation irrespective of the concentrations compared (10(7)-10(10)CFU), and a substantial increase of surface projections could be seen in PK-15 cells by scanning electron microscopy. This virulent strain was also able to invade effectively these epithelial cells, and the highest invasion capacity was reached at 180 min of infection. On the contrary, nonvirulent SW114 strain hardly adhered to PK-15 cells, and it did not invade these cells, thus suggesting that adherence and invasion of porcine kidney epithelial cells could be a virulence mechanism involved in the lesions caused by H. parasuis Nagasaki strain in this organ.
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Affiliation(s)
- Rafael Frandoloso
- Section of Microbiology and Immunology, Department of Animal Health, University of León, 24007 León, Spain
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30
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Leichtle A, Hernandez M, Lee J, Pak K, Webster NJ, Wollenberg B, Wasserman SI, Ryan AF. The role of DNA sensing and innate immune receptor TLR9 in otitis media. Innate Immun 2011; 18:3-13. [PMID: 21239460 DOI: 10.1177/1753425910393539] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Otitis media (OM), a common infectious disease in children, is associated with bacterial middle ear (ME) infection. Toll-like receptors (TLRs) are important mediators of innate immune responses, and TLR9 specifically recognizes the unmethylated cytidine-phosphate-guanosine (CpG) motifs in bacterial DNA. Additional sensors of foreign DNA have recently been identified. The role of DNA sensing and TLR9 was investigated in a murine model of OM induced by non-typeable Haemophilus influenzae (NTHi). Expression of genes related to DNA-sensing pathways involved in innate immunity was assessed via DNA microarray, qPCR and immunohistochemistry. Middle ear responses to NTHi were examined in wild-type and TLR9(-/-) mice by histopathology and bacterial culture. Expression of TLR9 signaling genes was modestly up-regulated during OM, as was TLR9 protein in both ME mucosal cells and infiltrating leukocytes. However, genes known to be regulated by CpG DNA were dramatically up-regulated, as were genes involved in DNA sensing by DIA, Pol-III and AIM2. Toll-like receptor 9 deletion significantly prolonged the inflammatory response induced by NTHi in the ME and delayed bacterial clearance. The results suggest that DNA sensing via TLR9 plays a role in OM pathogenesis and recovery. Alternative forms of DNA sensing may also contribute to OM.
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Affiliation(s)
- Anke Leichtle
- Department of Surgery/Otolaryngology, University of Lübeck, Lübeck, Germany
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