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Baffetta F, Buonsanti C, Moraschini L, Aprea S, Canè M, Lombardi S, Contorni M, Rondini S, Arora AK, Bardelli M, Finco O, Serruto D, Paccani SR. Lung mucosal immunity to NTHi vaccine antigens: Antibodies in sputum of chronic obstructive pulmonary disease patients. Hum Vaccin Immunother 2024; 20:2343544. [PMID: 38655676 PMCID: PMC11057560 DOI: 10.1080/21645515.2024.2343544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 04/12/2024] [Indexed: 04/26/2024] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a common chronic respiratory illness in older adults. A major cause of COPD-related morbidity and mortality is acute exacerbation of COPD (AECOPD). Bacteria in the lungs play a role in exacerbation development, and the most common pathogen is non-typeable Haemophilus influenzae (NTHi). A vaccine to prevent AECOPD containing NTHi surface antigens was tested in a clinical trial. This study measured IgG and IgA against NTHi vaccine antigens in sputum. Sputum samples from 40 COPD patients vaccinated with the NTHi vaccine were collected at baseline and 30 days after the second dose. IgG and IgA antibodies against the target antigens and albumin were analyzed in the sputum. We compared antibody signals before and after vaccination, analyzed correlation with disease severity and between sputum and serum samples, and assessed transudation. Antigen-specific IgG were absent before vaccination and present with high titers after vaccination. Antigen-specific IgA before and after vaccination were low but significantly different for two antigens. IgG correlated between sputum and serum, and between sputum and disease severity. Sputum albumin was higher in patients with severe COPD than in those with moderate COPD, suggesting changes in transudation played a role. We demonstrated that immunization with the NTHi vaccine induces antigen-specific antibodies in sputum. The correlation between IgG from sputum and serum and the presence of albumin in the sputum of severe COPD patients suggested transudation of antibodies from the serum to the lungs, although local IgG production could not be excluded.Clinical Trial Registration: NCT02075541.
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Affiliation(s)
| | | | | | | | | | | | | | - Simona Rondini
- GSK Vaccines Institute for Global Health (GVGH), Siena, Italy
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Rong Y, Liu Z, Wang H, Zhao Z. Comparison of the adherence of nontypeable haemophilus influenzae to lung epithelial cells. BMC Infect Dis 2024; 24:188. [PMID: 38347439 PMCID: PMC10863205 DOI: 10.1186/s12879-024-09085-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 02/01/2024] [Indexed: 02/15/2024] Open
Abstract
OBJECTIVE Nontypeable Haemophilus influenzae (NTHi) plays an important role in respiratory tract infections, and adherence to lung epithelial cells is the first step in lung infections. To explore the role of NTHi in childhood lung infections, a comparative study was conducted on the adherence of strains isolated from sputum culture and bronchoalveolar lavage fluid to A549 lung epithelial cells. METHODS Haemophilus influenzae strains were obtained from the sample bank of Shenzhen Children's Hospital, and identified as NTHi via PCR detection of the capsule gene bexA. NTHi obtained from healthy children's nasopharyngeal swabs culture were selected as the control group, and a comparative study was conducted on the adherence of strains isolated from sputum culture or bronchoalveolar lavage fluid of patients to A549 cells. RESULTS The adherence bacterial counts of NTHi isolated from the nasopharyngeal cultures of healthy children to A549 cells was 58.2 CFU. In patients with lung diseases, NTHi isolated from bronchoalveolar lavage fluid was 104.3 CFU, and from sputum cultures was 115.1 CFU, both of which were significantly higher in their adherence to A549 cells compared to the strains isolated from the healthy control group. There was no significant difference in adherence between the strains isolated from sputum cultures and bronchoalveolar lavage fluid (t = 0.5217, p = 0.6033). CONCLUSION NTHi played an important role in childhood pulmonary infections by enhancing its adherence to lung epithelial cells.
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Affiliation(s)
- Yuwei Rong
- Shantou University Medicine College, Shantou University (STU), Shantou, Guangdong, 515041, China
| | - Zihao Liu
- Shenzhen Children's Hospital, Shenzhen, Guangdong, 518038, China
| | - Heping Wang
- Shantou University Medicine College, Shantou University (STU), Shantou, Guangdong, 515041, China.
- Shenzhen Children's Hospital, Shenzhen, Guangdong, 518038, China.
| | - Zuguo Zhao
- Department of Microbiology, Immunology of Basical Medicine of Guangdong Medical University, Dongguan, Guangdong, 523810, China
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Lu D, Yang W, Zhang R, Li Y, Cheng T, Liao Y, Chen L, Liu H. Clinical Characteristics and Immune Responses in Children with Primary Ciliary Dyskinesia during Pneumonia Episodes: A Case-Control Study. CHILDREN (BASEL, SWITZERLAND) 2023; 10:1727. [PMID: 38002818 PMCID: PMC10670724 DOI: 10.3390/children10111727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 10/18/2023] [Accepted: 10/20/2023] [Indexed: 11/26/2023]
Abstract
OBJECTIVE This study explored the clinical features and immune responses of children with primary ciliary dyskinesia (PCD) during pneumonia episodes. METHODS The 61 children with PCD who were admitted to hospital because of pneumonia were retrospectively enrolled into this study between April 2017 and August 2022. A total of 61 children with pneumonia but without chronic diseases were enrolled as the control group. The clinical characteristics, levels of inflammatory indicators, pathogens, and imaging features of the lungs were compared between the two groups. RESULTS The PCD group had higher levels of lymphocytes (42.80% versus 36.00%, p = 0.029) and eosinophils (2.40% versus 1.25%, p = 0.020), but lower neutrophil counts (3.99 versus 5.75 × 109/L, p = 0.011), percentages of neutrophils (46.39% versus 54.24%, p = 0.014), CRP (0.40 versus 4.20 mg/L, p < 0.001) and fibrinogen (257.50 versus 338.00 mg/dL, p = 0.010) levels. Children with PCD and children without chronic diseases were both most commonly infected with Mycoplasma pneumoniae (24.6% versus 51.9%). Children with PCD had significantly more common imaging features, including mucous plugging (p = 0.042), emphysema (p = 0.007), bronchiectasis (p < 0.001), mosaic attenuation (p = 0.012), interstitial inflammation (p = 0.015), and sinusitis (p < 0.001). CONCLUSION PCD is linked to immune system impairment, which significantly contributes to our understanding of the pathophysiology of this entity.
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Affiliation(s)
- Danli Lu
- Department of Pediatric Pulmonology and Immunology, West China Second University Hospital, Sichuan University, Chengdu 610000, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu 610000, China
- NHC Key Laboratory of Chronobiology, Sichuan University, Chengdu 610000, China
- The Joint Laboratory for Lung Development and Related Diseases of West China Second University Hospital, School of Life Sciences of Fudan University, West China Institute of Women and Children’s Health, West China Second University Hospital, Sichuan University, Chengdu 610000, China
- Sichuan Birth Defects Clinical Research Center, West China Second University Hospital, Sichuan University, Chengdu 610000, China
| | - Wenhao Yang
- Department of Pediatric Pulmonology and Immunology, West China Second University Hospital, Sichuan University, Chengdu 610000, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu 610000, China
- NHC Key Laboratory of Chronobiology, Sichuan University, Chengdu 610000, China
- The Joint Laboratory for Lung Development and Related Diseases of West China Second University Hospital, School of Life Sciences of Fudan University, West China Institute of Women and Children’s Health, West China Second University Hospital, Sichuan University, Chengdu 610000, China
- Sichuan Birth Defects Clinical Research Center, West China Second University Hospital, Sichuan University, Chengdu 610000, China
| | - Rui Zhang
- Department of Pediatric Pulmonology and Immunology, West China Second University Hospital, Sichuan University, Chengdu 610000, China
| | - Yan Li
- Department of Pediatric Pulmonology and Immunology, West China Second University Hospital, Sichuan University, Chengdu 610000, China
| | - Tianyu Cheng
- Department of Pediatric Pulmonology and Immunology, West China Second University Hospital, Sichuan University, Chengdu 610000, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu 610000, China
- NHC Key Laboratory of Chronobiology, Sichuan University, Chengdu 610000, China
- The Joint Laboratory for Lung Development and Related Diseases of West China Second University Hospital, School of Life Sciences of Fudan University, West China Institute of Women and Children’s Health, West China Second University Hospital, Sichuan University, Chengdu 610000, China
- Sichuan Birth Defects Clinical Research Center, West China Second University Hospital, Sichuan University, Chengdu 610000, China
| | - Yue Liao
- Department of Pediatric Pulmonology and Immunology, West China Second University Hospital, Sichuan University, Chengdu 610000, China
| | - Lina Chen
- Department of Pediatric Pulmonology and Immunology, West China Second University Hospital, Sichuan University, Chengdu 610000, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu 610000, China
- NHC Key Laboratory of Chronobiology, Sichuan University, Chengdu 610000, China
- The Joint Laboratory for Lung Development and Related Diseases of West China Second University Hospital, School of Life Sciences of Fudan University, West China Institute of Women and Children’s Health, West China Second University Hospital, Sichuan University, Chengdu 610000, China
- Sichuan Birth Defects Clinical Research Center, West China Second University Hospital, Sichuan University, Chengdu 610000, China
| | - Hanmin Liu
- Department of Pediatric Pulmonology and Immunology, West China Second University Hospital, Sichuan University, Chengdu 610000, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Sichuan University, Ministry of Education, Chengdu 610000, China
- NHC Key Laboratory of Chronobiology, Sichuan University, Chengdu 610000, China
- The Joint Laboratory for Lung Development and Related Diseases of West China Second University Hospital, School of Life Sciences of Fudan University, West China Institute of Women and Children’s Health, West China Second University Hospital, Sichuan University, Chengdu 610000, China
- Sichuan Birth Defects Clinical Research Center, West China Second University Hospital, Sichuan University, Chengdu 610000, China
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Xiao J, Su L, Huang S, Liu L, Ali K, Chen Z. Epidemic Trends and Biofilm Formation Mechanisms of Haemophilus influenzae: Insights into Clinical Implications and Prevention Strategies. Infect Drug Resist 2023; 16:5359-5373. [PMID: 37605758 PMCID: PMC10440118 DOI: 10.2147/idr.s424468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 08/10/2023] [Indexed: 08/23/2023] Open
Abstract
Haemophilus influenzae (H. influenzae) is a significant pathogen responsible for causing respiratory tract infections and invasive diseases, leading to a considerable disease burden. The Haemophilus influenzae type b (Hib) conjugate vaccine has notably decreased the incidence of severe infections caused by Hib strains, and other non-typable H. influenzae (NTHi) serotypes have emerged as epidemic strains worldwide. As a result, the global epidemic trends and antibiotic resistance characteristics of H. influenzae have been altered. Researches on the virulence factors of H. influenzae, particularly the mechanisms underlying biofilm formation, and the development of anti-biofilm strategies hold significant clinical value. This article provides a summary of the epidemic trends, typing methods, virulence factors, biofilm formation mechanisms, and prevention strategies of H. influenzae. The increasing prevalence of NTHi strains and antibiotic resistance among H. influenzae, especially the high β-lactamase positivity and the emergence of BLNAR strains have increased clinical difficulties. Understanding its virulence factors, especially the formation mechanism of biofilm, and formulating effective anti-biofilm strategies may help to reduce the clinical impact. Therefore, future research efforts should focus on developing new approaches to prevent and control H. influenzae infections.
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Affiliation(s)
- Jiying Xiao
- Department of Pulmonology, Hangzhou Children’s Hospital, Hangzhou, Zhejiang, 310015, People’s Republic of China
| | - Lin Su
- Department of Pulmonology, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310052, People’s Republic of China
- National Clinical Research Center for Child Health, National Children’s Regional Medical Center, Hangzhou, Zhejiang, 310052, People’s Republic of China
| | - Shumin Huang
- Department of Pulmonology, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310052, People’s Republic of China
- National Clinical Research Center for Child Health, National Children’s Regional Medical Center, Hangzhou, Zhejiang, 310052, People’s Republic of China
| | - Lingyue Liu
- Department of Pulmonology, Hangzhou Children’s Hospital, Hangzhou, Zhejiang, 310015, People’s Republic of China
| | - Kamran Ali
- Department of Oncology, The Fourth Affiliated Hospital, International Institutes of Medicine, Zhejiang University School of Medicine, Yiwu, Zhejiang, 322000, People’s Republic of China
| | - Zhimin Chen
- Department of Pulmonology, Children’s Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310052, People’s Republic of China
- National Clinical Research Center for Child Health, National Children’s Regional Medical Center, Hangzhou, Zhejiang, 310052, People’s Republic of China
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Brown MA, Morgan SB, Donachie GE, Horton KL, Pavord ID, Arancibia-Cárcamo CV, Hinks TSC. Epithelial immune activation and intracellular invasion by non-typeable Haemophilus influenzae. Front Cell Infect Microbiol 2023; 13:1141798. [PMID: 37180449 PMCID: PMC10167379 DOI: 10.3389/fcimb.2023.1141798] [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: 01/10/2023] [Accepted: 04/04/2023] [Indexed: 05/16/2023] Open
Abstract
Type-2 low asthma affects 30-50% of people with severe asthma and includes a phenotype characterized by sputum neutrophilia and resistance to corticosteroids. Airways inflammation in type-2 low asthma or COPD is potentially driven by persistent bacterial colonization of the lower airways by bacteria such as non-encapsulated Haemophilus influenzae (NTHi). Although pathogenic in the lower airways, NTHi is a commensal of the upper airways. It is not known to what extent these strains can invade airway epithelial cells, persist intracellularly and activate epithelial cell production of proinflammatory cytokines, and how this differs between the upper and lower airways. We studied NTHi infection of primary human bronchial epithelial cells (PBECs), primary nasal epithelial cells (NECs) and epithelial cell lines from upper and lower airways. NTHi strains differed in propensity for intracellular and paracellular invasion. We found NTHi was internalized within PBECs at 6 h, but live intracellular infection did not persist at 24 h. Confocal microscopy and flow cytometry showed NTHi infected secretory, ciliated and basal PBECs. Infection of PBECs led to induction of CXCL8, interleukin (IL)-1β, IL-6 and TNF. The magnitude of cytokine induction was independent of the degree of intracellular invasion, either by differing strains or by cytochalasin D inhibition of endocytosis, with the exception of the inflammasome-induced mediator IL-1β. NTHi-induced activation of TLR2/4, NOD1/2 and NLR inflammasome pathways was significantly stronger in NECs than in PBECs. These data suggest that NTHi is internalized transiently by airway epithelial cells and has capacity to drive inflammation in airway epithelial cells.
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Affiliation(s)
- Mary A. Brown
- Respiratory Medicine Unit and National Institute for Health Research Oxford Biomedical Research Centre, Experimental Medicine Division, Nuffield Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Sophie B. Morgan
- Respiratory Medicine Unit and National Institute for Health Research Oxford Biomedical Research Centre, Experimental Medicine Division, Nuffield Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Gillian E. Donachie
- Respiratory Medicine Unit and National Institute for Health Research Oxford Biomedical Research Centre, Experimental Medicine Division, Nuffield Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Katie L. Horton
- School of Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom
| | - Ian D. Pavord
- Respiratory Medicine Unit and National Institute for Health Research Oxford Biomedical Research Centre, Experimental Medicine Division, Nuffield Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Carolina V. Arancibia-Cárcamo
- Translational Gastroenterology Unit, Nuffield Department of Medicine, Experimental Medicine, University of Oxford, Oxford, United Kingdom
| | - Timothy S. C. Hinks
- Respiratory Medicine Unit and National Institute for Health Research Oxford Biomedical Research Centre, Experimental Medicine Division, Nuffield Department of Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
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Patel P, Fogwe D, Patel T, Patil S, Bran-Acevedo A, Oba Y, Roland W. A Case of Acute Non-typeable Hemophilus influenza Infective Endocarditis in a Patient with Hypocomplementemia. IDCases 2023; 32:e01756. [PMID: 37122596 PMCID: PMC10130855 DOI: 10.1016/j.idcr.2023.e01756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 03/28/2023] [Indexed: 04/03/2023] Open
Abstract
Hemophilus influenzae is a gram-negative bacteria responsible for significant cases of invasive infections, especially in the pediatric population and in immunosuppressed adult patients. Before vaccination, most cases were frequently caused by capsulated or typeable variants. Due to the absence of effective vaccination against the nontypeable variant, it is now responsible for most invasive infections. Predisposing risk factors in adults include asplenia, hypocomplementemia, cancer, human immunodeficiency virus infection, and chronic cardiopulmonary disease. Immunity to the nontypeable variants causing disease is perplexing and not yet wholly described as they are genetically diverse. Infective endocarditis (IE) is a cardiac infection with devastating consequences if not detected earlier and treated appropriately. Gram-positive bacteria are the primary cause of IE overall, followed by gram-negative bacteria. Hemophilus species belong to the HACEK group of gram-negative bacteria responsible for causing IE in the pediatric population more than in adults. Hemophilus species, especially the nontypeable variant, is a rare cause of IE in adults. Here we present a case of IE due to Nontypeable Hemophilus influenzae in a 49-year-old caucasian male with hypocomplementemia.
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Rossing E, Pijnenborg JFA, Boltje TJ. Chemical tools to track and perturb the expression of sialic acid and fucose monosaccharides. Chem Commun (Camb) 2022; 58:12139-12150. [PMID: 36222364 PMCID: PMC9623448 DOI: 10.1039/d2cc04275d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 10/05/2022] [Indexed: 11/24/2022]
Abstract
The biosynthesis of glycans is a highly conserved biological process and found in all domains of life. The expression of cell surface glycans is increasingly recognized as a target for therapeutic intervention given the role of glycans in major pathologies such as cancer and microbial infection. Herein, we summarize our contributions to the development of unnatural monosaccharide derivatives to infiltrate and alter the expression of both mammalian and bacterial glycans and their therapeutic application.
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Affiliation(s)
- Emiel Rossing
- Department of Synthetic Organic Chemistry, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ, Nijmegen, The Netherlands.
| | - Johan F A Pijnenborg
- Department of Synthetic Organic Chemistry, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ, Nijmegen, The Netherlands.
| | - Thomas J Boltje
- Department of Synthetic Organic Chemistry, Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525AJ, Nijmegen, The Netherlands.
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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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Arenas J, Szabo Z, van der Wal J, Maas C, Riaz T, Tønjum T, Tommassen J. Serum proteases prevent bacterial biofilm formation: role of kallikrein and plasmin. Virulence 2021; 12:2902-2917. [PMID: 34903146 PMCID: PMC8677018 DOI: 10.1080/21505594.2021.2003115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Biofilm formation is a general strategy for bacterial pathogens to withstand host defense mechanisms. In this study, we found that serum proteases inhibit biofilm formation by Neisseria meningitidis, Neisseria gonorrhoeae, Haemophilus influenzae, and Bordetella pertussis. Confocal laser-scanning microscopy analysis revealed that these proteins reduce the biomass and alter the architecture of meningococcal biofilms. To understand the underlying mechanism, the serum was fractionated through size-exclusion chromatography and anion-exchange chromatography, and the composition of the fractions that retained anti-biofilm activity against N. meningitidis was analyzed by intensity-based absolute quantification mass spectrometry. Among the identified serum proteins, plasma kallikrein (PKLK), FXIIa, and plasmin were found to cleave neisserial heparin-binding antigen and the α-peptide of IgA protease on the meningococcal cell surface, resulting in the release of positively charged polypeptides implicated in biofilm formation by binding extracellular DNA. Further experiments also revealed that plasmin and PKLK inhibited biofilm formation of B. pertussis by cleaving filamentous hemagglutinin. We conclude that the proteolytic activity of serum proteases toward bacterial adhesins involved in biofilm formation could constitute a defense mechanism for the clearance of pathogens.
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Affiliation(s)
- Jesús Arenas
- Department of Molecular Microbiology and Institute of Biomembranes, Utrecht University, Utrecht, The Netherlands.,Unit of Microbiology and Immunology, Faculty of Veterinary, University of Zaragoza, Zaragoza, Spain
| | - Zalan Szabo
- Research and Development Department, U-Protein Express BV, Utrecht, The Netherlands
| | - Jelle van der Wal
- Department of Molecular Microbiology and Institute of Biomembranes, Utrecht University, Utrecht, The Netherlands
| | - Coen Maas
- Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Tahira Riaz
- Department of Microbiology, University of Oslo, Oslo, Norway
| | - Tone Tønjum
- Department of Microbiology, University of Oslo, Oslo, Norway
| | - Jan Tommassen
- Department of Molecular Microbiology and Institute of Biomembranes, Utrecht University, Utrecht, The Netherlands
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Weeks JR, Staples KJ, Spalluto CM, Watson A, Wilkinson TMA. The Role of Non-Typeable Haemophilus influenzae Biofilms in Chronic Obstructive Pulmonary Disease. Front Cell Infect Microbiol 2021; 11:720742. [PMID: 34422683 PMCID: PMC8373199 DOI: 10.3389/fcimb.2021.720742] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 07/15/2021] [Indexed: 11/13/2022] Open
Abstract
Non-typeable Haemophilus influenzae (NTHi) is an ubiquitous commensal-turned-pathogen that colonises the respiratory mucosa in airways diseases including Chronic Obstructive Pulmonary Disease (COPD). COPD is a progressive inflammatory syndrome of the lungs, encompassing chronic bronchitis that is characterised by mucus hypersecretion and impaired mucociliary clearance and creates a static, protective, humid, and nutrient-rich environment, with dysregulated mucosal immunity; a favourable environment for NTHi colonisation. Several recent large COPD cohort studies have reported NTHi as a significant and recurrent aetiological pathogen in acute exacerbations of COPD. NTHi proliferation has been associated with increased hospitalisation, disease severity, morbidity and significant lung microbiome shifts. However, some cohorts with patients at different severities of COPD do not report that NTHi is a significant aetiological pathogen in their COPD patients, indicating other obligate pathogens including Moraxella catarrhalis, Streptococcus pneumoniae and Pseudomonas aeruginosa as the cause. NTHi is an ubiquitous organism across healthy non-smokers, healthy smokers and COPD patients from childhood to adulthood, but it currently remains unclear why NTHi becomes pathogenic in only some cohorts of COPD patients, and what behaviours, interactions and adaptations are driving this susceptibility. There is emerging evidence that biofilm-phase NTHi may play a significant role in COPD. NTHi displays many hallmarks of the biofilm lifestyle and expresses key biofilm formation-promoting genes. These include the autoinducer-mediated quorum sensing system, epithelial- and mucus-binding adhesins and expression of a protective, self-produced polymeric substance matrix. These NTHi biofilms exhibit extreme tolerance to antimicrobial treatments and the immune system as well as expressing synergistic interspecific interactions with other lung pathogens including S. pneumoniae and M. catarrhalis. Whilst the majority of our understanding surrounding NTHi as a biofilm arises from otitis media or in-vitro bacterial monoculture models, the role of NTHi biofilms in the COPD lung is now being studied. This review explores the evidence for the existence of NTHi biofilms and their impact in the COPD lung. Understanding the nature of chronic and recurrent NTHi infections in acute exacerbations of COPD could have important implications for clinical treatment and identification of novel bactericidal targets.
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Affiliation(s)
- Jake R Weeks
- Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom
| | - Karl J Staples
- Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom.,National Institute for Health Research (NIHR) Southampton Biomedical Research Centre, Southampton General Hospital, Southampton, United Kingdom
| | - C Mirella Spalluto
- Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom.,National Institute for Health Research (NIHR) Southampton Biomedical Research Centre, Southampton General Hospital, Southampton, United Kingdom
| | - Alastair Watson
- Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom.,National Institute for Health Research (NIHR) Southampton Biomedical Research Centre, Southampton General Hospital, Southampton, United Kingdom.,Birmingham Medical School, University of Birmingham, Birmingham, United Kingdom
| | - Tom M A Wilkinson
- Clinical and Experimental Sciences, University of Southampton Faculty of Medicine, Southampton, United Kingdom.,National Institute for Health Research (NIHR) Southampton Biomedical Research Centre, Southampton General Hospital, Southampton, United Kingdom
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Unraveling Haemophilus influenzae virulence mechanisms enable discovery of new targets for antimicrobials and vaccines. Curr Opin Infect Dis 2021; 33:231-237. [PMID: 32304471 DOI: 10.1097/qco.0000000000000645] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE OF REVIEW The human upper respiratory tract is colonized with a variety of bacterial microorganisms including Haemophilus influenzae. The species H. influenzae consists of typeable and nontypeable H. influenzae (NTHi) variants. Typeable H. influenzae are subdivided into types a through f, based on the polysaccharide capsule, whereas the NTHi strains do not express a polysaccharide capsule. In this review, we highlight the current advances in the field of H. influenzae, with the focus on bacterial virulence mechanisms that facilitate bacterial colonization and disease, particularly for NTHi. RECENT FINDINGS In the past decade, it has become apparent that NTHi has the ability to cause invasive infections. Recently, a number of adhesins have been shown to be crucial for bacterial colonization and invasion and these proteins were investigated as vaccine antigens. Although NTHi lacks a polysaccharide capsule, it expresses lipooligosaccharide that contribute to adhesion and evasion of complement-mediated killing, both contributing to bacterial virulence, which could potentially be targeted by novel antimicrobial drugs or vaccines. SUMMARY The unraveling of H. influenzae virulence mechanisms resulted in the identification of promising targets for novel antimicrobials and vaccine antigens aiming to prevent or treat both typeable and nontypeable H. influenzae infections.
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12
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Short B, Carson S, Devlin AC, Reihill JA, Crilly A, MacKay W, Ramage G, Williams C, Lundy FT, McGarvey LP, Thornbury KD, Martin SL. Non-typeable Haemophilus influenzae chronic colonization in chronic obstructive pulmonary disease (COPD). Crit Rev Microbiol 2021; 47:192-205. [PMID: 33455514 DOI: 10.1080/1040841x.2020.1863330] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Haemophilus influenzae is the most common cause of bacterial infection in the lungs of chronic obstructive pulmonary disease (COPD) patients and contributes to episodes of acute exacerbation which are associated with increased hospitalization and mortality. Due to the ability of H. influenzae to adhere to host epithelial cells, initial colonization of the lower airways can progress to a persistent infection and biofilm formation. This is characterized by changes in bacterial behaviour such as reduced cellular metabolism and the production of an obstructive extracellular matrix (ECM). Herein we discuss the multiple mechanisms by which H. influenzae contributes to the pathogenesis of COPD. In particular, mechanisms that facilitate bacterial adherence to host airway epithelial cells, biofilm formation, and microbial persistence through immune system evasion and antibiotic tolerance will be discussed.
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Affiliation(s)
- Bryn Short
- University of the West of Scotland, Paisley, United Kingdom
| | - Stephen Carson
- School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Anna-Claire Devlin
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, United Kingdom
| | - James A Reihill
- School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
| | - Anne Crilly
- University of the West of Scotland, Paisley, United Kingdom
| | - William MacKay
- University of the West of Scotland, Paisley, United Kingdom
| | - Gordon Ramage
- Glasgow Biofilm Research Group, Oral Sciences, School of Medicine, Dentistry and Nursing, University of Glasgow, Glasgow, United Kingdom
| | - Craig Williams
- University of the West of Scotland, Paisley, United Kingdom
| | - Fionnuala T Lundy
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, United Kingdom
| | - Lorcan P McGarvey
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, United Kingdom
| | - Keith D Thornbury
- Smooth Muscle Research Group, Dundalk Institute of Technology, Dundalk, Ireland
| | - S Lorraine Martin
- School of Pharmacy, Queen's University Belfast, Belfast, United Kingdom
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13
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Baddal B. Characterization of biofilm formation and induction of apoptotic DNA fragmentation by nontypeable Haemophilus influenzae on polarized human airway epithelial cells. Microb Pathog 2020; 141:103985. [PMID: 31968224 DOI: 10.1016/j.micpath.2020.103985] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 01/14/2020] [Accepted: 01/15/2020] [Indexed: 10/25/2022]
Abstract
Nontypeable Haemophilus influenzae (NTHi) is a common airway commensal and opportunistic pathogen that persists within biofilm communities in vivo. Biofilm studies so far are mainly based on assays on plastic surfaces. The aim of this work was to investigate the capacity of clinical NTHi strains to form biofilm structures on polarized Calu-3 human airway epithelial cells and primary normal human bronchial epithelial cells and to characterize the biofilm architecture. Formation of adherent NTHi biofilms post colonization of host cells at multiple time-points was evaluated using confocal laser scanning microscopy and electron microscopy. NTHi biofilms were analyzed in terms of biofilm height and presence of extracellular matrix components, and their apoptotic effects on epithelial cells were measured by TUNEL assay. Strain Fi176 was observed to form robust biofilms on airway epithelia over time, while disrupting the integrity of Calu-3 monolayer by 72 h of co-culture. NTHi biofilms were observed to induce apoptotic DNA fragmentation in host cells at 24 h post infection. Biofilm formation on cell monolayers by Fi176ΔpilA strain was markedly reduced compared to WT strain. Biofilm inhibition and disruption assays by crystal violet staining indicated that DNA and proteins are part of NTHi biofilms in vitro. Our findings highlight critical stages of NTHi pathogenesis following host colonization and provide useful biofilm models for future antimicrobial drug discovery investigations.
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Affiliation(s)
- Buket Baddal
- Department of Medical Microbiology and Clinical Microbiology, Faculty of Medicine, Near East University, 99138, Nicosia, Cyprus; Microbial Pathogenesis Research Group, DESAM Institute, Near East University, Nicosia, Cyprus.
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14
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Franchi T, Eaton S, De Coppi P, Giuliani S. The emerging role of immunothrombosis in paediatric conditions. Pediatr Res 2019; 86:19-27. [PMID: 30808021 DOI: 10.1038/s41390-019-0343-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/15/2019] [Accepted: 02/01/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND Immunothrombosis is a physiological process based on the release of neutrophil extracellular traps (NETs) to immobilise, contain and kill bacteria. This is an innate immune response in which the local activation of blood coagulation exerts the critical protective function during microbial infection. In recent years, there has been much interest in the adult literature about the key role of immunothrombosis in pathologic states including thrombosis, cancer, sepsis and trauma. Currently, little research has been done into its role in paediatric conditions. METHODS We conducted a literature search of the National Library of Medicine (MEDLINE/PubMed) from the years 2000 to May 2018 and qualitatively identified 24 relevant papers. References of articles included for full-text review were checked for relevant publications. RESULTS Our aim is to summarise the most relevant evidences regarding an excessive production or defective removal of NETs in paediatric conditions. In particular, we have divided the role of immunothrombosis into acute (sepsis, necrotising enterocolitis, otitis media, neonatal arterial ischaemic stroke, haemolytic anaemic diseases) and chronic (systemic lupus erythematous, type 1 diabetes mellitus, respiratory diseases, graft-versus-host disease) conditions to find important similarities in their pathophysiology. CONCLUSION The field of immunothrombosis in paediatric conditions is still in its infancy. We have presented multiple pathways of NET-induced disease together with possible areas of future research and treatments.
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Affiliation(s)
- Thomas Franchi
- The Medical School, Faculty of Medicine, Dentistry and Health, University of Sheffield, Sheffield, UK
| | - Simon Eaton
- Stem Cells and Regenerative Medicine Section, University College London-Institute of Child Health, London, UK
| | - Paolo De Coppi
- Stem Cells and Regenerative Medicine Section, University College London-Institute of Child Health, London, UK.,Specialist Neonatal and Paediatric Surgery Department, Great Ormond Street Hospital for Children, London, UK
| | - Stefano Giuliani
- Specialist Neonatal and Paediatric Surgery Department, Great Ormond Street Hospital for Children, London, UK.
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15
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Hamilos DL. Biofilm Formations in Pediatric Respiratory Tract Infection Part 2: Mucosal Biofilm Formation by Respiratory Pathogens and Current and Future Therapeutic Strategies to Inhibit Biofilm Formation or Eradicate Established Biofilm. Curr Infect Dis Rep 2019; 21:8. [DOI: 10.1007/s11908-019-0657-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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16
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Insights into the population structure and pan-genome of Haemophilus influenzae. INFECTION GENETICS AND EVOLUTION 2018; 67:126-135. [PMID: 30391557 DOI: 10.1016/j.meegid.2018.10.025] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 10/20/2018] [Accepted: 10/30/2018] [Indexed: 12/25/2022]
Abstract
The human-restricted bacterium Haemophilus influenzae is responsible for respiratory infections in both children and adults. While colonization begins in the upper airways, it can spread throughout the respiratory tract potentially leading to invasive infections. Although the spread of H. influenzae serotype b (Hib) has been prevented by vaccination, the emergence of infections by other serotypes as well as by non-typeable isolates (NTHi) have been observed, prompting the need for novel prevention strategies. Here, we aimed to study the population structure of H. influenzae and to get some insights into its pan-genome. We studied 305H. influenzae strains, enrolling 217 publicly available genomes, as well as 88 newly sequenced H. influenzae invasive strains isolated in Portugal, spanning a 24-year period. NTHi isolates presented a core-SNP-based genetic diversity about 10-fold higher than the one observed for Hib. The analysis of key factors involved in pathogenesis, such as lipooligosaccharides, hemagglutinating pili and High Molecular Weight-adhesins, suggests that NTHi shape its virulence repertoire, either by acquisition and loss of genes or by SNP-based diversification, likely towards host immune evasion and persistence. Discreet NTHi subpopulations structures are proposed based on core-genome supported with 17 candidate genetic markers identified in the accessory genome. Additionally, this study provides two bioinformatics tools for in silico rapid identification of H. influenzae serotypes and NTHi clades previously proposed, obviating laboratory-based demanding procedures. The present study constitutes an important genomic framework that could lay way for future studies on the genetic determinants underlying invasiveness and disease and population structure of H. influenzae.
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17
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Heise T, Langereis JD, Rossing E, de Jonge MI, Adema GJ, Büll C, Boltje TJ. Selective Inhibition of Sialic Acid-Based Molecular Mimicry in Haemophilus influenzae Abrogates Serum Resistance. Cell Chem Biol 2018; 25:1279-1285.e8. [PMID: 29983272 DOI: 10.1016/j.chembiol.2018.05.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 02/26/2018] [Accepted: 05/25/2018] [Indexed: 01/22/2023]
Abstract
Pathogens such as non-typeable Haemophilus influenzae (NTHi) evade the immune system by presenting host-derived sialic acids. NTHi cannot synthesize sialic acids and therefore needs to utilize sialic acids originating from host tissue. Here we report sialic acid-based probes to visualize and inhibit the transfer of host sialic acids to NTHi. Inhibition of sialic acid utilization by NTHi enhanced serum-mediated killing. Furthermore, in an in vitro model of the human respiratory tract, we demonstrate efficient inhibition of sialic acid transfer from primary human bronchial epithelial cells to NTHi using bioorthogonal chemistry.
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Affiliation(s)
- Torben Heise
- Cluster of Molecular Chemistry, Institute for Molecules and Materials, Radboud University, Nijmegen 6525 AJ, the Netherlands
| | - Jeroen D Langereis
- Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen 6525 GA, the Netherlands; Radboud Centre for Infectious Diseases, Radboudumc, Nijmegen 6525 GA, the Netherlands.
| | - Emiel Rossing
- Cluster of Molecular Chemistry, Institute for Molecules and Materials, Radboud University, Nijmegen 6525 AJ, the Netherlands
| | - Marien I de Jonge
- Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboudumc, Nijmegen 6525 GA, the Netherlands; Radboud Centre for Infectious Diseases, Radboudumc, Nijmegen 6525 GA, the Netherlands
| | - Gosse J Adema
- Radiotherapy & OncoImmunology Laboratory, Department of Radiation Oncology, Radboudumc, Nijmegen 6525 GA, the Netherlands
| | - Christian Büll
- Radiotherapy & OncoImmunology Laboratory, Department of Radiation Oncology, Radboudumc, Nijmegen 6525 GA, the Netherlands
| | - Thomas J Boltje
- Cluster of Molecular Chemistry, Institute for Molecules and Materials, Radboud University, Nijmegen 6525 AJ, the Netherlands.
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18
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Ahearn CP, Gallo MC, Murphy TF. Insights on persistent airway infection by non-typeable Haemophilus influenzae in chronic obstructive pulmonary disease. Pathog Dis 2017; 75:3753446. [PMID: 28449098 PMCID: PMC5437125 DOI: 10.1093/femspd/ftx042] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 04/28/2017] [Indexed: 12/21/2022] Open
Abstract
Non-typeable Haemophilus influenzae (NTHi) is the most common bacterial cause of infection of the lower airways in adults with chronic obstructive pulmonary disease (COPD). Infection of the COPD airways causes acute exacerbations, resulting in substantial morbidity and mortality. NTHi has evolved multiple mechanisms to establish infection in the hostile environment of the COPD airways, allowing the pathogen to persist in the airways for months to years. Persistent infection of the COPD airways contributes to chronic airway inflammation that increases symptoms and accelerates the progressive loss of pulmonary function, which is a hallmark of the disease. Persistence mechanisms of NTHi include the expression of multiple redundant adhesins that mediate binding to host cellular and extracellular matrix components. NTHi evades host immune recognition and clearance by invading host epithelial cells, forming biofilms, altering gene expression and displaying surface antigenic variation. NTHi also binds host serum factors that confer serum resistance. Here we discuss the burden of COPD and the role of NTHi infections in the course of the disease. We provide an overview of NTHi mechanisms of persistence that allow the pathogen to establish a niche in the hostile COPD airways.
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Affiliation(s)
- Christian P. Ahearn
- Department of Microbiology and Immunology, University at Buffalo, Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY 14203, USA
- Clinical and Translational Research Center, University at Buffalo, Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY 14203, USA
| | - Mary C. Gallo
- Department of Microbiology and Immunology, University at Buffalo, Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY 14203, USA
- Clinical and Translational Research Center, University at Buffalo, Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY 14203, USA
| | - Timothy F. Murphy
- Department of Microbiology and Immunology, University at Buffalo, Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY 14203, USA
- Clinical and Translational Research Center, University at Buffalo, Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY 14203, USA
- Division of Infectious Disease, Department of Medicine, University at Buffalo, Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY 14203, USA
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19
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Sriram KB, Cox AJ, Clancy RL, Slack MPE, Cripps AW. Nontypeable Haemophilus influenzae and chronic obstructive pulmonary disease: a review for clinicians. Crit Rev Microbiol 2017; 44:125-142. [PMID: 28539074 DOI: 10.1080/1040841x.2017.1329274] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Chronic Obstructive Pulmonary Disease (COPD) is a leading cause of morbidity and mortality worldwide. In the lower airways of COPD patients, bacterial infection is a common phenomenon and Haemophilus influenzae is the most commonly identified bacteria. Haemophilus influenzae is divided into typeable and nontypeable (NTHi) strains based on the presence or absence of a polysaccharide capsule. While NTHi is a common commensal in the human nasopharynx, it is associated with considerable inflammation when it is present in the lower airways of COPD patients, resulting in morbidity due to worsening symptoms and increased frequency of COPD exacerbations. Treatment of lower airway NTHi infection with antibiotics, though successful in the short term, does not offer long-term protection against reinfection, nor does it change the course of the disease. Hence, there has been much interest in the development of an effective NTHi vaccine. This review will summarize the current literature concerning the role of NTHi infections in COPD patients and the consequences of using prophylactic antibiotics in patients with COPD. There is particular focus on the rationale, findings of clinical studies and possible future directions of NTHi vaccines in patients with COPD.
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Affiliation(s)
- Krishna Bajee Sriram
- a Department of Respiratory Medicine , Gold Coast University Hospital, Gold Coast Health , Southport , Australia.,b Griffith University School of Medicine , Southport , Australia
| | - Amanda J Cox
- c Menzies Health Institute , Griffith University School of Medical Science , Gold Coast , Australia
| | - Robert L Clancy
- d Faculty of Health and Medicine , University of Newcastle , Callaghan , Australia
| | - Mary P E Slack
- b Griffith University School of Medicine , Southport , Australia
| | - Allan W Cripps
- b Griffith University School of Medicine , Southport , Australia
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20
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Ishak A, Everard ML. Persistent and Recurrent Bacterial Bronchitis-A Paradigm Shift in Our Understanding of Chronic Respiratory Disease. Front Pediatr 2017; 5:19. [PMID: 28261574 PMCID: PMC5309219 DOI: 10.3389/fped.2017.00019] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 01/24/2017] [Indexed: 02/01/2023] Open
Abstract
The recent recognition that the conducting airways are not "sterile" and that they have their own dynamic microbiome, together with the rapid advances in our understanding of microbial biofilms and their roles in the causation of respiratory diseases (such as chronic bronchitis, sinusitis, and chronic otitis media), permit us to update the "vicious circle" hypothesis of the causation of bronchiectasis. This proposes that chronic inflammation driven by persistent bacterial bronchitis (PBB) causes damage to both the epithelium, resulting in impaired mucociliary clearance, and to the airway wall, which eventually manifests as bronchiectasis. The link between a "chronic bronchitis" and a persistence of bacterial pathogens, such as non-typable Haemophilus influenzae, was first made more than 100 years ago, and its probable role in the causation of bronchiectasis was proposed soon afterward. The recognition that the "usual suspects" are adept at forming biofilms and hence are able to persist and dominate the normal dynamically changing "healthy microbiome" of the conducting airways provides an explanation for the chronic colonization of the bronchi and for the associated chronic neutrophil-dominated inflammation characteristic of a PBB. Understanding the complex interaction between the host and the microbial communities of the conducting airways in health and disease will be a key component in optimizing pulmonary health in the future.
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Affiliation(s)
- Alya Ishak
- Department of Respiratory Medicine, Princess Margaret Hospital, Subiaco, WA, Australia
| | - Mark L. Everard
- Department of Respiratory Medicine, Princess Margaret Hospital, Subiaco, WA, Australia
- University of Western Australia, Crawley, WA, Australia
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21
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Bacterial Lysis through Interference with Peptidoglycan Synthesis Increases Biofilm Formation by Nontypeable Haemophilus influenzae. mSphere 2017; 2:mSphere00329-16. [PMID: 28124027 PMCID: PMC5244263 DOI: 10.1128/msphere.00329-16] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Accepted: 12/31/2016] [Indexed: 11/20/2022] Open
Abstract
Most, if not all, bacteria form a biofilm, a multicellular structure that protects them from antimicrobial actions of the host immune system and affords resistance to antibiotics. The latter is especially disturbing with the increase in multiresistant bacterial clones worldwide. Bacterial biofilm formation is a multistep process that starts with surface adhesion, after which attached bacteria divide and give rise to biomass. The actual steps required for Haemophilus influenzae biofilm formation are largely not known. We show that interference with peptidoglycan biosynthesis increases biofilm formation because of the release of bacterial genomic DNA. Subinhibitory concentrations of β-lactam antibiotics, which are often prescribed to treat H. influenzae infections, increase biofilm formation through a similar mechanism. Therefore, when β-lactam antibiotics do not reach their MIC in vivo, they might not only drive selection for β-lactam-resistant clones but also increase biofilm formation and resistance to other antimicrobial compounds. Nontypeable Haemophilus influenzae (NTHi) is an opportunistic pathogen that mainly causes otitis media in children and community-acquired pneumonia or exacerbations of chronic obstructive pulmonary disease in adults. A large variety of studies suggest that biofilm formation by NTHi may be an important step in the pathogenesis of this bacterium. However, the underlying mechanisms involved in this process are poorly elucidated. In this study, we used a transposon mutant library to identify bacterial genes involved in biofilm formation. The growth and biofilm formation of 4,172 transposon mutants were determined, and the involvement of the identified genes in biofilm formation was validated in in vitro experiments. Here, we present experimental data showing that increased bacterial lysis, through interference with peptidoglycan synthesis, results in elevated levels of extracellular DNA, which increased biofilm formation. Interestingly, similar results were obtained with subinhibitory concentrations of β-lactam antibiotics, known to interfere with peptidoglycan synthesis, but such an effect does not appear with other classes of antibiotics. These results indicate that treatment with β-lactam antibiotics, especially for β-lactam-resistant NTHi isolates, might increase resistance to antibiotics by increasing biofilm formation. IMPORTANCE Most, if not all, bacteria form a biofilm, a multicellular structure that protects them from antimicrobial actions of the host immune system and affords resistance to antibiotics. The latter is especially disturbing with the increase in multiresistant bacterial clones worldwide. Bacterial biofilm formation is a multistep process that starts with surface adhesion, after which attached bacteria divide and give rise to biomass. The actual steps required for Haemophilus influenzae biofilm formation are largely not known. We show that interference with peptidoglycan biosynthesis increases biofilm formation because of the release of bacterial genomic DNA. Subinhibitory concentrations of β-lactam antibiotics, which are often prescribed to treat H. influenzae infections, increase biofilm formation through a similar mechanism. Therefore, when β-lactam antibiotics do not reach their MIC in vivo, they might not only drive selection for β-lactam-resistant clones but also increase biofilm formation and resistance to other antimicrobial compounds.
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22
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Pizzutto SJ, Hare KM, Upham JW. Bronchiectasis in Children: Current Concepts in Immunology and Microbiology. Front Pediatr 2017; 5:123. [PMID: 28611970 PMCID: PMC5447051 DOI: 10.3389/fped.2017.00123] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 05/08/2017] [Indexed: 12/26/2022] Open
Abstract
Bronchiectasis is a complex chronic respiratory condition traditionally characterized by chronic infection, airway inflammation, and progressive decline in lung function. Early diagnosis and intensive treatment protocols can stabilize or even improve the clinical prognosis of children with bronchiectasis. However, understanding the host immunologic mechanisms that contribute to recurrent infection and prolonged inflammation has been identified as an important area of research that would contribute substantially to effective prevention strategies for children at risk of bronchiectasis. This review will focus on the current understanding of the role of the host immune response and important pathogens in the pathogenesis of bronchiectasis (not associated with cystic fibrosis) in children.
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Affiliation(s)
- Susan J Pizzutto
- Child Health Division, Menzies School of Health Research, Darwin, NT, Australia
| | - Kim M Hare
- Child Health Division, Menzies School of Health Research, Darwin, NT, Australia
| | - John W Upham
- Department of Respiratory Medicine, Princess Alexandra Hospital, Brisbane, QLD, Australia.,School of Medicine, The University of Queensland, Brisbane, QLD, Australia
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23
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Martínez-Reséndez MF, González-Chávez JM, Garza-González E, Castro-Fuentes LN, Gutiérrez-Ferman JL, Echániz-Aviles G, Camacho-Ortíz A, Carnalla-Barajas MN, Soto-Noguerón A, Maldonado-Garza HJ, Hernández-Balboa CL, Llaca-Díaz JM, Flores-Treviño S. Non-typeable Haemophilus influenzae biofilm production and severity in lower respiratory tract infections in a tertiary hospital in Mexico. J Med Microbiol 2016; 65:1385-1391. [DOI: 10.1099/jmm.0.000369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Michel Fernando Martínez-Reséndez
- Servicio de Infectología, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
| | - Juan Manuel González-Chávez
- Departamento de Medicina Interna, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
| | - Elvira Garza-González
- Servicio de Gastroenterología, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
- Departamento de Patología Clínica, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
| | - Lorena Nefertiti Castro-Fuentes
- Servicio de Gastroenterología, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
| | - Jessica Lizzeth Gutiérrez-Ferman
- Servicio de Gastroenterología, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
| | - Gabriela Echániz-Aviles
- Departamento de Evaluación de Vacunas, Instituto Nacional de Salud Pública. Universidad No. 655 Colonia Santa María Ahuacatitlán, Cerrada Los Pinos y Caminera C.P. 62100. Cuernavaca, Morelos, Mexico
| | - Adrián Camacho-Ortíz
- Servicio de Infectología, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
| | - María Noemí Carnalla-Barajas
- Departamento de Evaluación de Vacunas, Instituto Nacional de Salud Pública. Universidad No. 655 Colonia Santa María Ahuacatitlán, Cerrada Los Pinos y Caminera C.P. 62100. Cuernavaca, Morelos, Mexico
| | - Araceli Soto-Noguerón
- Departamento de Evaluación de Vacunas, Instituto Nacional de Salud Pública. Universidad No. 655 Colonia Santa María Ahuacatitlán, Cerrada Los Pinos y Caminera C.P. 62100. Cuernavaca, Morelos, Mexico
| | - Héctor Jesús Maldonado-Garza
- Servicio de Gastroenterología, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
| | - Cristina Liliana Hernández-Balboa
- Servicio de Infectología, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
| | - Jorge M. Llaca-Díaz
- Departamento de Patología Clínica, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
| | - Samantha Flores-Treviño
- Servicio de Gastroenterología, Hospital Universitario Dr José Eleuterio González, Universidad Autónoma de Nuevo León, Av. Francisco I. Madero Pte. S/N y Av. Gonzalitos, Col. Mitras Centro, 64460 Monterrey, Nuevo León, Mexico
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Domenech M, Pedrero-Vega E, Prieto A, García E. Evidence of the presence of nucleic acids and β-glucan in the matrix of non-typeable Haemophilus influenzae in vitro biofilms. Sci Rep 2016; 6:36424. [PMID: 27805043 PMCID: PMC5090351 DOI: 10.1038/srep36424] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 10/14/2016] [Indexed: 12/21/2022] Open
Abstract
Non-typeable Haemophilus influenzae (NTHi) is a Gram-negative bacterium that frequently colonizes the human nasopharynx; it is a common cause of chronic and recurrent otitis media in children and of exacerbations of chronic obstructive pulmonary disease. To date, no exopolysaccharide clearly contributing to NTHi biofilms has been identified. Consequently, there is some debate as to whether NTHi forms biofilms during colonization and infection. The present work shows that NTHi can form biofilms in vitro, producing an extracellular matrix composed of proteins, nucleic acids, and a β-glucan. Extracellular DNA, visualized by immunostaining and using fluorochromes, is an important component of this matrix and appears to be essential in biofilm maintenance. Extracellular RNA appears to be required only in the first steps of biofilm formation. Evidence of a matrix polysaccharide was obtained by staining with Calcofluor white M2R and by disaggregating biofilms with cellulase. Using strain 54997, residues of Glcp(1→4) in the NTHi biofilm were confirmed by gas-liquid chromatography-mass spectrometry. Evidence that N-acetyl-L-cysteine shows notable killing activity towards in vitro NTHi biofilm-forming bacteria is also provided.
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Affiliation(s)
- Mirian Domenech
- Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Monforte de Lemos 3–5, 28029 Madrid, Spain
| | - Elena Pedrero-Vega
- Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Alicia Prieto
- Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Ernesto García
- Departamento de Microbiología Molecular y Biología de las Infecciones, Centro de Investigaciones Biológicas (CSIC), Ramiro de Maeztu 9, 28040 Madrid, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Monforte de Lemos 3–5, 28029 Madrid, Spain
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25
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Duell BL, Su YC, Riesbeck K. Host-pathogen interactions of nontypeable Haemophilus influenzae: from commensal to pathogen. FEBS Lett 2016; 590:3840-3853. [PMID: 27508518 DOI: 10.1002/1873-3468.12351] [Citation(s) in RCA: 84] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 08/01/2016] [Accepted: 08/05/2016] [Indexed: 11/09/2022]
Abstract
Nontypeable Haemophilus influenzae (NTHi) is a commensal microbe often isolated from the upper and lower respiratory tract. This bacterial species can cause sinusitis, acute otitis media in preschool children, exacerbations in patients suffering from chronic obstructive pulmonary disease, as well as conjunctivitis and bacteremia. Since the introduction of a vaccine against H. influenzae serotype b in the 1990s, the burden of H. influenzae-related infections has been increasingly dominated by NTHi. Understanding the ability of NTHi to cause infection is currently an expanding area of study. NTHi is able to exert differential binding to the host tissue through the use of a broad range of adhesins. NTHi survival in the host is multifaceted, that is, using virulence factors involved in complement resistance, biofilm, modified immunoglobulin responses, and, finally, formation and utilization of host proteins as a secondary strategy of increasing the adhesive ability.
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Affiliation(s)
- Benjamin Luke Duell
- Clinical Microbiology, Department of Translational Medicine, Lund University, Malmö, Sweden
| | - Yu-Ching Su
- Clinical Microbiology, Department of Translational Medicine, Lund University, Malmö, Sweden
| | - Kristian Riesbeck
- Clinical Microbiology, Department of Translational Medicine, Lund University, Malmö, Sweden
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Dagan R, Pelton S, Bakaletz L, Cohen R. Prevention of early episodes of otitis media by pneumococcal vaccines might reduce progression to complex disease. THE LANCET. INFECTIOUS DISEASES 2016; 16:480-92. [PMID: 27036355 DOI: 10.1016/s1473-3099(15)00549-6] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 12/08/2015] [Accepted: 12/17/2015] [Indexed: 12/22/2022]
Abstract
Otitis media is a common childhood infection of the middle ear and a major cause of morbidity. This multifactorial disease manifests as a spectrum of clinical syndromes from uncomplicated acute otitis media to more complex recurrent and chronic cases (frequently polymicrobial), with the major pathogens involved being Streptococcus pneumoniae and non-typeable Haemophilus influenzae. Pneumococcal conjugate vaccines (PCVs) target only a few serotypes that cause otitis media; however, results from studies suggest that existing PCVs can prevent early episodes of disease associated with vaccine serotypes, resulting in a reduction of subsequent complex cases caused by non-vaccine serotypes and other otopathogens, which contribute considerably to the disease burden. In this Review, we discuss the role of pneumococcus in the disease continuum and assess clinical evidence showing the effect of prevention of early episodes on the complex interplay between bacterial species implicated in otitis media.
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Affiliation(s)
- Ron Dagan
- Pediatric Infectious Disease Unit, Soroka University Medical Center and the Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
| | | | - Lauren Bakaletz
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Robert Cohen
- Université Paris Est, IMRB-GRC GEMINI, and Unité Court Séjour, Petits Nourrissons, Centre Hospitalier Intercommunal de Créteil, Paris, France
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27
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Exopolysaccharide Production and Biofilm Formation by Histophilus somni. Curr Top Microbiol Immunol 2016; 396:149-60. [PMID: 26853691 DOI: 10.1007/82_2015_5013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The biofilm matrix of Histophilus somni is a complex architecture that differs substantially in structure between a pathogenic and commensal isolate examined. Overall, most pathogenic isolates produce more biofilm than commensal isolates. A major component of the biofilm is exopolysaccharide (EPS), which is also produced in greater quantity in the pathogenic isolate than in the commensal isolate studied. The EPS is composed of a D-mannan polymer, with occasional galactose residues present on side chains, similar in composition to that of yeast mannan. When grown in the presence of sialic acid, the biofilm EPS becomes sialylated and the amino sugars N-acetylglucosamine and N-acetylgalactosamine can be detected. In vitro biofilm formation follows a typical 4-stage growth curve, characterized by attachment, growth, maturation, and detachment. Following experimental challenge, formation of an H. somni biofilm has been demonstrated in cardiopulmonary tissue, often with Pasteurella multocida cohabitating the biofilm. A recently developed diagnostic test can detect antibodies to the EPS only in animals with systemic disease due to H. somni and is therefore capable of distinguishing between healthy animals colonized with H. somni and animals with systemic disease.
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Yonker LM, Cigana C, Hurley BP, Bragonzi A. Host-pathogen interplay in the respiratory environment of cystic fibrosis. J Cyst Fibros 2015; 14:431-439. [PMID: 25800687 DOI: 10.1016/j.jcf.2015.02.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 02/11/2015] [Accepted: 02/19/2015] [Indexed: 01/01/2023]
Abstract
Significant advances have been made in the understanding of disease progression in cystic fibrosis (CF), revealing a complex interplay between host and pathogenic organisms. The diverse CF microbiota within the airway activates an aberrant immune response that is ineffective in clearing infection. An appreciation of how the CF host immune system interacts with these organisms is crucial to understanding the pathogenesis of CF pulmonary disease. Here we discuss the microbial complexity present in the lungs of individuals with CF, review emerging concepts of innate and adaptive immune responses to pathogens that chronically inhabit the CF lung, and discuss therapies that target the aberrant inflammatory response that characterizes CF. A greater understanding of the underlying mechanisms will shed light on pathogenesis and guide more targeted therapies in the future that serve to reduce infection, minimize lung pathology, and improve the quality of life for patients with CF.
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Affiliation(s)
- Lael M Yonker
- Mucosal Immunology & Biology Research Center, Pediatrics, Harvard Medical School, Massachusetts General Hospital for Children , Charlestown, MA, U.S.A
| | - Cristina Cigana
- Infections and Cystic Fibrosis Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milano, Italy
| | - Bryan P Hurley
- Mucosal Immunology & Biology Research Center, Pediatrics, Harvard Medical School, Massachusetts General Hospital for Children , Charlestown, MA, U.S.A
| | - Alessandra Bragonzi
- Infections and Cystic Fibrosis Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Milano, Italy
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Obaid NA, Jacobson GA, Tristram S. Relationship between clinical site of isolation and ability to form biofilms in vitro in nontypeable Haemophilus influenzae. Can J Microbiol 2015; 61:243-5. [PMID: 25706230 DOI: 10.1139/cjm-2014-0763] [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] [Indexed: 11/22/2022]
Abstract
Nontypeable Haemophilus influenzae (NTHi) is an opportunistic pathogen associated with a range of infections, including various lower respiratory infections, otitis media, and conjunctivitis. There is some debate as to whether or not NTHi produces biofilms and, if so, whether or not this is relevant to pathogenesis. Although many studies have examined the association between in vitro biofilm formation and isolates from a specific infection type, few have made comparisons from isolates from a broad range of isolates grouped by clinical source. In our study 50 NTHi from different clinical sources, otitis media, conjunctivitis, lower respiratory tract infections in both cystic fibrosis and non-cystic fibrosis patients, and nasopharyngeal carriage, plus 10 nasopharyngeal isolates of the commensal Haemophilus haemolyticus were tested for the ability to form biofilm by using a static microtitre plate crystal violet assay. A high degree of variation in biofilm forming ability was observed across all isolates, with no statistically significant differences observed between the groups, with the exception of the isolates from conjunctivitis. These isolates had uniformly lower biofilm forming ability compared with isolates from the other groups (p < 0.005).
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Affiliation(s)
- Najla A Obaid
- School of Medicine, University of Tasmania, Private Bag 26, Hobart, 7005, Tasmania, Australia
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Haemophilus influenzae: recent advances in the understanding of molecular pathogenesis and polymicrobial infections. Curr Opin Infect Dis 2015; 27:268-74. [PMID: 24699388 DOI: 10.1097/qco.0000000000000056] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE OF REVIEW Non-typeable Haemophilus influenzae (NTHi) is a human-specific mucosal pathogen and one of the most common causes of bacterial infections in children and patients with chronic obstructive pulmonary disease. It is also frequently found in polymicrobial superinfections. Great strides have recently been made in the understanding of the molecular mechanisms underlying NTHi pathogenesis. RECENT FINDINGS By using new methodology, such as experimental human colonization models and whole-genome approaches, investigators have shed light upon the various strategies of NTHi that are involved in pathogenesis. These include the escape of the mucociliary elevator, evasion of host immunity, survival in environments with scarce nutrients, and finally participation in polymicrobial infections. Lipooligosaccharide branching, proteinous adhesins, metabolic adaption to nutrient availability and many scavenging systems are implicated in these processes. Interestingly, genome-based studies comparing virulent and commensal strains have identified many hypothetical proteins as virulence determinants, suggesting that much regarding the molecular pathogenesis of NTHi remains to be solved. SUMMARY NTHi is an opportunistic pathogen and highly specialized colonizer of the human respiratory tract that has developed intricate mechanisms to establish growth and survival in the human host. Continued research is needed to further elucidate NTHi host-pathogen and pathogen-pathogen interactions.
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Finney LJ, Ritchie A, Pollard E, Johnston SL, Mallia P. Lower airway colonization and inflammatory response in COPD: a focus on Haemophilus influenzae. Int J Chron Obstruct Pulmon Dis 2014; 9:1119-32. [PMID: 25342897 DOI: 10.2147/copd.s54477] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Bacterial infection of the lower respiratory tract in chronic obstructive pulmonary disease (COPD) patients is common both in stable patients and during acute exacerbations. The most frequent bacteria detected in COPD patients is Haemophilus influenzae, and it appears this organism is uniquely adapted to exploit immune deficiencies associated with COPD and to establish persistent infection in the lower respiratory tract. The presence of bacteria in the lower respiratory tract in stable COPD is termed colonization; however, there is increasing evidence that this is not an innocuous phenomenon but is associated with airway inflammation, increased symptoms, and increased risk for exacerbations. In this review, we discuss host immunity that offers protection against H. influenzae and how disturbance of these mechanisms, combined with pathogen mechanisms of immune evasion, promote persistence of H. influenzae in the lower airways in COPD. In addition, we examine the role of H. influenzae in COPD exacerbations, as well as interactions between H. influenzae and respiratory virus infections, and review the role of treatments and their effect on COPD outcomes. This review focuses predominantly on data derived from human studies but will refer to animal studies where they contribute to understanding the disease in humans.
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Affiliation(s)
- Lydia J Finney
- Airway Disease Infection Section, National Heart and Lung Institute, Imperial College, London, United Kingdom
| | - Andrew Ritchie
- Airway Disease Infection Section, National Heart and Lung Institute, Imperial College, London, United Kingdom
| | | | - Sebastian L Johnston
- Airway Disease Infection Section, National Heart and Lung Institute, Imperial College, London, United Kingdom
| | - Patrick Mallia
- Airway Disease Infection Section, National Heart and Lung Institute, Imperial College, London, United Kingdom
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Mizrahi A, Cohen R, Varon E, Bonacorsi S, Bechet S, Poyart C, Levy C, Raymond J. Non typable-Haemophilus influenzae biofilm formation and acute otitis media. BMC Infect Dis 2014; 14:400. [PMID: 25037572 PMCID: PMC4223365 DOI: 10.1186/1471-2334-14-400] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 07/12/2014] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Non-typable Haemophilus influenzae (NT-Hi) infection is frequently associated with acute otitis media (AOM) treatment failure, recurrence or chronic otitis media. Persistence of otopathogens in a biofilm-structured community was implicated in these situations. Here, we compared biofilm production by H. influenzae strains obtained by culture of middle ear fluid (MEF) from children with AOM treatment failure and by strains isolated from nasopharyngeal (NP) samples from healthy children or those with AOM (first episode or recurrence). We aimed to evaluate an association of clinical signs and in vitro biofilm formation and establish risk factors of carrying a biofilm-producing strain. METHODS We used a modification of the microtiter plate assay with crystal violet staining to compare biofilm production by 216 H. influenzae strains: 41 in MEF from children with AOM treatment failure (group MEF), 43 in NP samples from healthy children (NP group 1), 88 in NP samples from children with a first AOM episode (NP group 2, n = 43) or recurrent (NP group 3, n = 45) and 44 in NP samples from children with AOM associated with conjunctivitis (NP group 4). RESULTS At all, 106/216 (49%) H. influenzae strains produced biofilm as did 26/43 (60.5%) in NP samples from healthy children. Biofilm production in MEF samples and NP samples did not significantly differ (40.5% vs 60.5%, 55.8%, 56.8% and 31.1% for NP groups 1, 2, 3 and 4, respectively). On multivariate analysis, only presence of conjunctivitis was significantly associated with low biofilm production (OR = 0.3, CI [0.16-0.60], p = 0.001). The ampicillin resistance of H. influenzae produced by penicillin-binding protein modification was significantly associated with low biofilm production (p = 0.029). CONCLUSION We found no association of biofilm production and AOM treatment failure or recurrence. Biofilm production was low from H. influenzae strains associated with conjunctivitis-otitis syndrome and from strains with modified penicillin-binding protein.
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Affiliation(s)
- Assaf Mizrahi
- Université Paris Descartes, Hôpital Cochin, Bactériologie, 27 rue du Faubourg Saint Jacques, 75679 Paris cedex 14, France
| | | | - Emmanuelle Varon
- Université Paris Descartes, Hôpital Georges Pompidou, Bactériologie, Paris, France
| | | | | | - Claire Poyart
- Université Paris Descartes, Hôpital Cochin, Bactériologie, 27 rue du Faubourg Saint Jacques, 75679 Paris cedex 14, France
| | | | - Josette Raymond
- Université Paris Descartes, Hôpital Cochin, Bactériologie, 27 rue du Faubourg Saint Jacques, 75679 Paris cedex 14, France
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Rogers GB, van der Gast CJ, Serisier DJ. Predominant pathogen competition and core microbiota divergence in chronic airway infection. ISME JOURNAL 2014; 9:217-25. [PMID: 25036925 DOI: 10.1038/ismej.2014.124] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 06/10/2014] [Accepted: 06/13/2014] [Indexed: 01/11/2023]
Abstract
Chronic bacterial lung infections associated with non-cystic fibrosis bronchiectasis represent a substantial and growing health-care burden. Where Pseudomonas aeruginosa is the numerically dominant species within these infections, prognosis is significantly worse. However, in many individuals, Haemophilus influenzae predominates, a scenario associated with less severe disease. The mechanisms that determine which pathogen is most abundant are not known. We hypothesised that the distribution of H. influenzae and P. aeruginosa would be consistent with strong interspecific competition effects. Further, we hypothesised that where P. aeruginosa is predominant, it is associated with a distinct 'accessory microbiota' that reflects a significant interaction between this pathogen and the wider bacterial community. To test these hypotheses, we analysed 16S rRNA gene pyrosequencing data generated previously from 60 adult bronchiectasis patients, whose airway microbiota was dominated by either P. aeruginosa or H. influenzae. The relative abundances of the two dominant species in their respective groups were not significantly different, and when present in the opposite pathogen group the two species were found to be in very low abundance, if at all. These findings are consistent with strong competition effects, moving towards competitive exclusion. Ordination analysis indicated that the distribution of the core microbiota associated with each pathogen, readjusted after removal of the dominant species, was significantly divergent (analysis of similarity (ANOSIM), R=0.07, P=0.019). Taken together, these findings suggest that both interspecific competition and also direct and/or indirect interactions between the predominant species and the wider bacterial community may contribute to the predominance of P. aeruginosa in a subset of bronchiectasis lung infections.
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Affiliation(s)
- Geraint B Rogers
- 1] SAHMRI Infection and Immunity Theme, School of Medicine, Flinders University, Adelaide, South Australia, Australia [2] Immunity, Infection, and Inflammation Program, Mater Research Institute, University of Queensland, Translational Research Institute, Woolloongabba, Queensland, Australia
| | | | - David J Serisier
- 1] Immunity, Infection, and Inflammation Program, Mater Research Institute, University of Queensland, Translational Research Institute, Woolloongabba, Queensland, Australia [2] Department of Respiratory Medicine, Mater Adult Hospital, South Brisbane, Queensland, Australia
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García-Cobos S, Moscoso M, Pumarola F, Arroyo M, Lara N, Pérez-Vázquez M, Aracil B, Oteo J, García E, Campos J. Frequent carriage of resistance mechanisms to β-lactams and biofilm formation in Haemophilus influenzae causing treatment failure and recurrent otitis media in young children. J Antimicrob Chemother 2014; 69:2394-9. [PMID: 24891432 DOI: 10.1093/jac/dku158] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Non-typeable Haemophilus influenzae are a major cause of acute otitis media (AOM), including chronic and recurrent otitis in young children. The objective of this study was to determine whether non-typeable H. influenzae isolates causing these infections produce biofilms and carry resistance mechanisms to β-lactams. METHODS A collection of 48 H. influenzae isolates was obtained by tympanocentesis or from otorrhoea samples from individual patients <3 years of age and diagnosed with recurrent or treatment failure AOM. Each isolate was surveyed for the presence of blaTEM genes, amino acid substitutions in the transpeptidase domain of penicillin-binding protein 3 (PBP3) and biofilm formation in microtitre plates. RESULTS In 43 of the 48 isolates (89.6%), at least one of the three tested conditions was identified: biofilm formation (83.3%) and resistance mechanisms to β-lactams (33.3%), modifications in the transpeptidase domain of PBP3 being the most prevalent (22.9%), followed by β-lactamase production (10.4%). Additionally, 13 (27.1%) isolates had two or more of these three traits. In relation to biofilm formation, those isolates with an amoxicillin MIC ≤ 0.5 mg/L had higher optical density values than isolates with an amoxicillin MIC ≥ 1 mg/L (Mann-Whitney U-test, P=0.048). CONCLUSIONS These findings suggest that the successful treatment of non-typeable H. influenzae causing chronic and recurrent AOM in young children may be compromised by the high biofilm-forming capacity of the isolates and the presence of β-lactam resistance mechanisms, particularly PBP3 mutations.
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Affiliation(s)
- Silvia García-Cobos
- Antibiotic and Haemophilus Laboratory, Bacteriology Service, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain Department of Medical Microbiology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Miriam Moscoso
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Félix Pumarola
- Servicio de Otorrinolaringología, Hospital Universitario Vall d'Hebron, Barcelona, Spain
| | - Margarita Arroyo
- Antibiotic and Haemophilus Laboratory, Bacteriology Service, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Noelia Lara
- Antibiotic and Haemophilus Laboratory, Bacteriology Service, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - María Pérez-Vázquez
- Antibiotic and Haemophilus Laboratory, Bacteriology Service, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Belén Aracil
- Antibiotic and Haemophilus Laboratory, Bacteriology Service, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Jesús Oteo
- Antibiotic and Haemophilus Laboratory, Bacteriology Service, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain
| | - Ernesto García
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - José Campos
- Antibiotic and Haemophilus Laboratory, Bacteriology Service, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, Madrid, Spain Consejo Superior de Investigaciones Científicas, Madrid, Spain
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Puig C, Marti S, Hermans PWM, de Jonge MI, Ardanuy C, Liñares J, Langereis JD. Incorporation of phosphorylcholine into the lipooligosaccharide of nontypeable Haemophilus influenzae does not correlate with the level of biofilm formation in vitro. Infect Immun 2014; 82:1591-9. [PMID: 24452688 PMCID: PMC3993405 DOI: 10.1128/iai.01445-13] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Accepted: 01/20/2014] [Indexed: 12/20/2022] Open
Abstract
Nontypeable Haemophilus influenzae (NTHi) is an opportunistic pathogen that causes otitis media in children and community-acquired pneumonia or exacerbations of chronic obstructive pulmonary disease in adults. A large variety of studies suggest that biofilm formation by NTHi may be an important step in the pathogenesis of this bacterium. The objective of this report was to determine the relationship between the presence of phosphorylcholine in the lipooligosaccharide of NTHi and the level of biofilm formation. The study was performed on 111 NTHi clinical isolates collected from oropharyngeal samples of healthy children, middle ear fluid of children with otitis media, and sputum samples of patients with chronic obstructive pulmonary disease or community-acquired pneumonia. NTHi clinical isolates presented a large variation in the level of biofilm formation in a static assay and phosphorylcholine content. Isolates collected from the oropharynx and middle ear fluid of children tended to have more phosphorylcholine and made denser biofilms than isolates collected from sputum samples of patients with chronic obstructive pulmonary disease or community-acquired pneumonia. No correlation was observed between biofilm formation and the presence of phosphorylcholine in the lipooligosaccharide for either planktonic or biofilm growth. This lack of correlation was confirmed by abrogating phosphorylcholine incorporation into lipooligosaccharide through licA gene deletion, which had strain-specific effects on biofilm formation. Altogether, we present strong evidence to conclude that there is no correlation between biofilm formation in a static assay and the presence of phosphorylcholine in lipooligosaccharide in a large collection of clinical NTHi isolates collected from different groups of patients.
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Affiliation(s)
- Carmen Puig
- Microbiology Department, Hospital Universitari de Bellvitge-Universitat de Barcelona, IDIBELL, Barcelona, Spain
- Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud University Medical Center, Nijmegen, The Netherlands
- CIBER de Enfermedades Respiratorias, ISCIII, Madrid, Spain
| | - Sara Marti
- Microbiology Department, Hospital Universitari de Bellvitge-Universitat de Barcelona, IDIBELL, Barcelona, Spain
- Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud University Medical Center, Nijmegen, The Netherlands
- CIBER de Enfermedades Respiratorias, ISCIII, Madrid, Spain
| | - Peter W. M. Hermans
- Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Marien I. de Jonge
- Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Carmen Ardanuy
- Microbiology Department, Hospital Universitari de Bellvitge-Universitat de Barcelona, IDIBELL, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, ISCIII, Madrid, Spain
| | - Josefina Liñares
- Microbiology Department, Hospital Universitari de Bellvitge-Universitat de Barcelona, IDIBELL, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, ISCIII, Madrid, Spain
| | - Jeroen D. Langereis
- Laboratory of Pediatric Infectious Diseases, Department of Pediatrics, Radboud University Medical Center, Nijmegen, The Netherlands
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Ishak N, Tikhomirova A, Bent SJ, Ehrlich GD, Hu FZ, Kidd SP. There is a specific response to pH by isolates of Haemophilus influenzae and this has a direct influence on biofilm formation. BMC Microbiol 2014; 14:47. [PMID: 24555828 PMCID: PMC3938079 DOI: 10.1186/1471-2180-14-47] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 02/19/2014] [Indexed: 12/22/2022] Open
Abstract
Background Haemophilus influenzae colonizes the nasopharynx as a commensal. Strain-specific factors allow some strains to migrate to particular anatomical niches, such as the middle ear, bronchi or blood, and induce disease by surviving within the conditions present at these sites in the body. It is established that H. influenzae colonization and in some cases survival is highly dependent on their ability to form a biofilm. Biofilm formation is a key trait in the development of chronic infection by certain isolates. This is exemplified by the contrast between the biofilm-forming strains found in middle ear infections and those isolates that survive within the blood and are rarely associated with biofilm development. Results Screening a group of H. influenzae strains revealed only slight variations in their growth across a range of pH conditions. However, some isolates responded to a pH of 8.0 by the formation of a biofilm. While the type b capsular blood isolate Eagan did not form a biofilm and grew at the same rate regardless of pH 6.8-8.0, transcriptomic analyses demonstrated that at pH 8.0 it uniquely induced a gluconate-uptake and metabolism pathway, which concurrently imports H+. A non-typeable H. influenzae, isolated from the middle ear, induced biofilm formation at pH 8.0, and at this pH it induced a series of iron acquisition genes, consistent with previous studies linking iron homeostasis to biofilm lifestyle. Conclusions Different strains of H. influenzae cope with changes in environmental factors using strain-specific mechanisms. These pathways define the scope and mode of niche-survival for an isolate. The pH is a property that is different from the middle ear (at least pH 8.0) compared to other sites that H. influenzae can colonize and infect. The transcriptional response to increasing pH by H. influenzae varies between strains, and pH is linked to pathways that allow strains to either continue free-living growth or induction of a biofilm. We showed that a biofilm-forming isolate induced iron metabolism pathways, whereas a strain that does not form biofilm at increasing pH induced mechanisms for growth and pH homeostasis based on sugar acid transport.
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Affiliation(s)
| | | | | | | | | | - Stephen P Kidd
- Research Centre for Infectious Diseases, The University of Adelaide, North Terrace Campus, Adelaide, South Australia 5005, Australia.
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Su YC, Resman F, Hörhold F, Riesbeck K. Comparative genomic analysis reveals distinct genotypic features of the emerging pathogen Haemophilus influenzae type f. BMC Genomics 2014; 15:38. [PMID: 24438474 PMCID: PMC3928620 DOI: 10.1186/1471-2164-15-38] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 01/09/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The incidence of invasive disease caused by encapsulated Haemophilus influenzae type f (Hif) has increased in the post-H. influenzae type b (Hib) vaccine era. We previously annotated the first complete Hif genome from a clinical isolate (KR494) that caused septic shock and necrotizing myositis. Here, the full genome of Hif KR494 was compared to sequenced reference strains Hib 10810, capsule type d (Hid) Rd Kw20, and finally nontypeable H. influenzae 3655. The goal was to identify possible genomic characteristics that may shed light upon the pathogenesis of Hif. RESULTS The Hif KR494 genome exhibited large regions of synteny with other H. influenzae, but also distinct genome rearrangements. A predicted Hif core genome of 1390 genes was shared with the reference strains, and 6 unique genomic regions comprising half of the 191 unique coding sequences were revealed. The majority of these regions were inserted genetic fragments, most likely derived from the closely-related Haemophilus spp. including H. aegyptius, H. haemolyticus and H. parainfluenzae. Importantly, the KR494 genome possessed several putative virulence genes that were distinct from non-type f strains. These included the sap2 operon, aef3 fimbriae, and genes for kanamycin nucleotidyltranserase, iron-utilization proteins, and putative YadA-like trimeric autotransporters that may increase the bacterial virulence. Furthermore, Hif KR494 lacked a hisABCDEFGH operon for de novo histidine biosynthesis, hmg locus for lipooligosaccharide biosynthesis and biofilm formation, the Haemophilus antibiotic resistance island and a Haemophilus secondary molybdate transport system. We confirmed the histidine auxotrophy and kanamycin resistance in Hif by functional experiments. Moreover, the pattern of unique or missing genes of Hif KR494 was similar in 20 Hif clinical isolates obtained from different years and geographical areas. A cross-species comparison revealed that the Hif genome shared more characteristics with H. aegyptius than Hid and NTHi. CONCLUSIONS The genomic comparative analyses facilitated identification of genotypic characteristics that may be related to the specific virulence of Hif. In relation to non-type f H. influenzae strains, the Hif genome contains differences in components involved in metabolism and survival that may contribute to its invasiveness.
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Affiliation(s)
| | | | | | - Kristian Riesbeck
- Medical Microbiology, Department of Laboratory Medicine Malmö, Lund University, Jan Waldenströms gata 59, SE-205 02 Malmö, Sweden.
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