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Hansen K, Yamba Yamba L, Wasserstrom L, Rünow E, Göransson T, Nilsson A, Ahl J, Riesbeck K. Exploring the microbial landscape: uncovering the pathogens associated with community-acquired pneumonia in hospitalized patients. Front Public Health 2023; 11:1258981. [PMID: 38152664 PMCID: PMC10752608 DOI: 10.3389/fpubh.2023.1258981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 11/10/2023] [Indexed: 12/29/2023] Open
Abstract
Objectives This study aimed to investigate the etiology, clinical features, and outcomes of community-acquired pneumonia (CAP) in adults. Understanding the causative pathogens is essential for effective treatment and prevention. Design Between 2016-2018, 518 hospitalized adults with CAP and 241 controls without symptoms were prospectively enrolled. Urine samples were collected for pneumococcal urinary antigen tests and nasopharyngeal swabs for viral and bacterial analysis, combined with routine diagnostic care. Results Among the included CAP patients, Streptococcus pneumoniae was the most common pathogen, detected in 28% of patients, followed by Haemophilus influenzae in 16%. Viruses were identified in 28%, and concurrent viruses and bacteria were detected in 15%. There was no difference in mortality, length of stay, or symptoms at hospitalization when comparing patients with bacterial, viral, or mixed etiologies. Among the control subjects without respiratory symptoms, S. pneumoniae, H. influenzae, or Moraxella catarrhalis were detected in 5-7%, and viruses in 7%. Conclusion Streptococcus pneumoniae emerged as the predominant cause of CAP, followed closely by viruses and H. influenzae. Intriguingly, symptoms and outcome were similar regardless of etiology. These findings highlight the complexity of this respiratory infection and emphasize the importance of comprehensive diagnostic and treatment strategies.Clinical Trial Registration: ClinicalTrials.gov, identifier [NCT03606135].
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Affiliation(s)
- Karin Hansen
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine Lund University, Malmö, Sweden
- Infectious Diseases, Department of Translational Medicine, Faculty of Medicine Lund University, Malmö, Sweden
| | - Linda Yamba Yamba
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine Lund University, Malmö, Sweden
| | - Lisa Wasserstrom
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine Lund University, Malmö, Sweden
- Clinical Microbiology, Infection Control and Prevention, Laboratory Medicine, Lund, Sweden
| | - Elisabeth Rünow
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine Lund University, Malmö, Sweden
- Infectious Diseases, Department of Translational Medicine, Faculty of Medicine Lund University, Malmö, Sweden
| | - Tommy Göransson
- Clinical Microbiology, Infection Control and Prevention, Laboratory Medicine, Lund, Sweden
| | - Anna Nilsson
- Infectious Diseases, Department of Translational Medicine, Faculty of Medicine Lund University, Malmö, Sweden
| | - Jonas Ahl
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine Lund University, Malmö, Sweden
- Infectious Diseases, Department of Translational Medicine, Faculty of Medicine Lund University, Malmö, Sweden
| | - Kristian Riesbeck
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine Lund University, Malmö, Sweden
- Clinical Microbiology, Infection Control and Prevention, Laboratory Medicine, Lund, Sweden
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Zhou Y, Wang Y, Cheng J, Zhao X, Liang Y, Wu J. Molecular epidemiology and antimicrobial resistance of Haemophilus influenzae in Guiyang, Guizhou, China. Front Public Health 2022; 10:947051. [PMID: 36530676 PMCID: PMC9751421 DOI: 10.3389/fpubh.2022.947051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 11/11/2022] [Indexed: 12/03/2022] Open
Abstract
Background The widespread use of antimicrobials and Haemophilus influenzae type b (Hib) vaccine worldwide has altered the epidemiological patterns of invasive H. influenzae. Nonetheless, little is currently known on the epidemiological characteristics of H. influenzae in Guiyang, Guizhou, China. Objective To determine the serotype distribution, antimicrobial resistance and Multilocus Sequence Typing (MLST) of H. influenzae in hospitalized patients in Guiyang City. Methods A total of 196 clinical isolates from hospitalized patients were collected. Serotypes were determined according to the specific capsule gene, bexA, amplified by PCR. According to the guidelines of Clinical and Laboratory Standards Institute (CLSI) 2020 drug susceptibility tested, and the results determined. The chromogenic cephalosporin nitrocefin method was used to detect β-lactamase production, β-lactamase negative, ampicillin-resistant (BLNAR) strains were detected by PCR amplification and sequencing of the penicillin-binding protein 3 (PBP3) locus of ftsI. Multilocus Sequence Typing was performed for molecular typing. Results All isolates studied were non-typeable H. influenzae (NTHi). Most patients originated from the pediatrics department (78.6%, 154/196), and suffered from lung with respiratory tract infection (pneumonia and bronchitis, 68.4%, 134/196). The resistance rates of ampicillin, cefaclor and azithromycin were 71.4% (140/196), 36.7% (72/196) and 34.2% (67/196), respectively. 40.3% (79/196) of strains were β-lactamase positive ampicillin-resistant (BLPAR). All BLPAR carried the TEM-1 gene. 9.2% (18/196) were β-lactamase negative ampicillin-resistant strains (BLNAR). The PBP3 mutation was detected in the ampicillin-resistant strains (n = 113), of which 18 belonged to group IIa. A total of 49 sequence types (ST) and 23 clonal complexes (CC) were detected, among which CC107 (ST107, n = 27; ST1002, n = 5; ST1218, n = 5) was the most frequent clonal complexes. BLPAR isolates mostly belonged to ST107 (20/79), while BLNAR was predominantly distributed in ST12 (5/18). Conclusion H. influenzae infections are predominately caused by genetically diverse NTHi among hospitalized patients in Guiyang. The prevalence of β-lactamase production and PBP3 mutation may contribute to the high local ampicillin resistance rate.
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Affiliation(s)
- Yuhong Zhou
- The Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, School of Public Health, Guizhou Medical University, Guiyang, China
| | - Yu Wang
- Department of Clinical Laboratory, The First People's Hospital of Guiyang, Guiyang, China,*Correspondence: Yu Wang
| | - Jinzhi Cheng
- School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China
| | - Xue Zhao
- Department of Clinical Laboratory, The First People's Hospital of Guiyang, Guiyang, China
| | - Yuedong Liang
- Guiyang Public Health Treatment Center, Guiyang, China
| | - Jiahong Wu
- School of Basic Medical Sciences, Guizhou Medical University, Guiyang, China,Jiahong Wu
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Tønnessen R, García I, Debech N, Lindstrøm JC, Wester AL, Skaare D. Molecular epidemiology and antibiotic resistance profiles of invasive Haemophilus influenzae from Norway 2017–2021. Front Microbiol 2022; 13:973257. [PMID: 36106084 PMCID: PMC9467436 DOI: 10.3389/fmicb.2022.973257] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
Invasive Haemophilus influenzae (Hi) disease has decreased in countries that included Hi type b (Hib) vaccination in their childhood immunization programs in the 1990s. Non-typeable (NT) and non-b strains are now the leading causes of invasive Hi disease in Europe, with most cases reported in young children and the elderly. Concerningly, no vaccines toward such strains are available and beta-lactam resistance is increasing. We describe the epidemiology of invasive Hi disease reported to the Norwegian Surveillance System for Communicable Diseases (MSIS) (2017–2021, n = 407). Whole-genome sequencing (WGS) was performed on 245 isolates. We investigated the molecular epidemiology (core genome phylogeny) and the presence of antibiotic resistance markers (including chromosomal mutations associated with beta-lactam or quinolone resistance). For isolates characterized with both WGS and phenotypic antibiotic susceptibility testing (AST) (n = 113) we assessed correlation between resistance markers and susceptibility categorization by calculation of sensitivity, specificity, and predictive values. Incidence rates of invasive Hi disease in Norway ranged from 0.7 to 2.3 per 100,000 inhabitants/year (mean 1.5 per 100,000) and declined during the COVID-19 pandemic. The bacterial population consisted of two major phylogenetic groups with subclustering by serotype and multi-locus sequence type (ST). NTHi accounted for 71.8% (176). The distribution of STs was in line with previous European reports. We identified 13 clusters, including four encapsulated and three previously described international NTHi clones with blaTEM–1 (ST103) or altered PBP3 (rPBP3) (ST14/IIA and ST367/IIA). Resistance markers were detected in 25.3% (62/245) of the isolates, with blaTEM–1 (31, 50.0%) and rPBP3 (28, 45.2%) being the most frequent. All isolates categorized as resistant to aminopenicillins, tetracycline or chloramphenicol possessed relevant resistance markers, and the absence of relevant substitutions in PBP3 and GyrA/ParC predicted susceptibility to cefotaxime, ceftriaxone, meropenem and quinolones. Among the 132 WGS-only isolates, one isolate had PBP3 substitutions associated with resistance to third-generation cephalosporins, and one isolate had GyrA/ParC alterations associated with quinolone resistance. The detection of international virulent and resistant NTHi clones underlines the need for a global molecular surveillance system. WGS is a useful supplement to AST and should be performed on all invasive isolates.
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Affiliation(s)
- Ragnhild Tønnessen
- Department of Infection Control and Vaccines, Norwegian Institute of Public Health, Oslo, Norway
- European Public Health Microbiology Training Program (EUPHEM), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
- *Correspondence: Ragnhild Tønnessen,
| | - Ignacio García
- Department of Bacteriology, Norwegian Institute of Public Health, Oslo, Norway
| | - Nadia Debech
- Department of Bacteriology, Norwegian Institute of Public Health, Oslo, Norway
| | | | | | - Dagfinn Skaare
- Department of Microbiology, Vestfold Hospital Trust, Tønsberg, Norway
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López-López N, Gil-Campillo C, Díez-Martínez R, Garmendia J. Learning from -omics strategies applied to uncover Haemophilus influenzae host-pathogen interactions: Current status and perspectives. Comput Struct Biotechnol J 2021; 19:3042-3050. [PMID: 34136102 PMCID: PMC8178019 DOI: 10.1016/j.csbj.2021.05.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 05/11/2021] [Accepted: 05/11/2021] [Indexed: 11/15/2022] Open
Abstract
Haemophilus influenzae has contributed to key bacterial genome sequencing hallmarks, as being not only the first bacterium to be genome-sequenced, but also starring the first genome-wide analysis of chromosomes directly transformed with DNA from a divergent genotype, and pioneering Tn-seq methodologies. Over the years, the phenomenal and constantly evolving development of -omic technologies applied to a whole range of biological questions of clinical relevance in the H. influenzae-host interplay, has greatly moved forward our understanding of this human-adapted pathogen, responsible for multiple acute and chronic infections of the respiratory tract. In this way, essential genes, virulence factors, pathoadaptive traits, and multi-layer gene expression regulatory networks with both genomic and epigenomic complexity levels are being elucidated. Likewise, the unstoppable increasing whole genome sequencing information underpinning H. influenzae great genomic plasticity, mainly when referring to non-capsulated strains, poses major challenges to understand the genomic basis of clinically relevant phenotypes and even more, to clearly highlight potential targets of clinical interest for diagnostic, therapeutic or vaccine development. We review here how genomic, transcriptomic, proteomic and metabolomic-based approaches are great contributors to our current understanding of the interactions between H. influenzae and the human airways, and point possible strategies to maximize their usefulness in the context of biomedical research and clinical needs on this human-adapted bacterial pathogen.
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Affiliation(s)
- Nahikari López-López
- Instituto de Agrobiotecnología, Consejo Superior de Investigaciones Científicas (IdAB-CSIC)-Gobierno de Navarra, Mutilva, Spain
| | - Celia Gil-Campillo
- Instituto de Agrobiotecnología, Consejo Superior de Investigaciones Científicas (IdAB-CSIC)-Gobierno de Navarra, Mutilva, Spain
| | | | - Junkal Garmendia
- Instituto de Agrobiotecnología, Consejo Superior de Investigaciones Científicas (IdAB-CSIC)-Gobierno de Navarra, Mutilva, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain
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5
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McElligott M, Meyler K, Bennett D, Mulhall R, Drew RJ, Cunney R. Epidemiology of Haemophilus influenzae in the Republic of Ireland, 2010–2018. Eur J Clin Microbiol Infect Dis 2020; 39:2335-2344. [DOI: 10.1007/s10096-020-03971-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 06/28/2020] [Indexed: 11/24/2022]
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Abstract
Antimicrobial resistance is a global concern, and prudent use of antibiotics is essential to preserve the current armamentarium of effective drugs. Acute respiratory tract infection is the most common reason for antibiotic prescription in adults. In particular, community-acquired pneumonia poses a significant health challenge and economic burden globally, especially in the current landscape of a dense and aging population. By updating the knowledge on the common antimicrobial-resistant pathogens in community-acquired respiratory tract infections, their prevalence, and resistance may pave the way to enhancing appropriate antibiotic use in the ambulatory and health care setting.
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7
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Dong Q, Shi W, Cheng X, Chen C, Meng Q, Yao K, Qian S. Widespread of non-typeable Haemophilus influenzae with high genetic diversity after two decades use of Hib vaccine in China. J Clin Lab Anal 2019; 34:e23145. [PMID: 31846125 PMCID: PMC7171301 DOI: 10.1002/jcla.23145] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 11/08/2019] [Accepted: 11/12/2019] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND The aim of this study was to analyze the microbiological characteristics of nasopharyngeal carriage Haemophilus influenzae isolates collected from children with respiratory infections in Beijing hospital and Youyang Hospital of China. METHODS The serotypes of all isolates were determined using latex agglutinated antisera (a-f). The minimum inhibitory concentrations (MICs) of 11 antibiotics were determined using E-test strips. For the beta-lactamase-negative ampicillin-resistant (BLNAR) isolates, ftsI gene was sequenced based on fragments amplified by PCR. STs of H influenzae isolates were determined by multi-locus sequence typing. RESULTS The overall carriage rate of H influenzae in the study population was 9.1% (362/3984). One hundred and ninety H influenzae isolates which were selected in our study were non-typeable (NTHi) and 44 (23.2%) of them were positive for β-lactamase. All isolates were susceptible to ceftriaxone and levofloxacin. Susceptibility rates to erythromycin and sulfamethoxazole-trimethoprim in Beijing were significantly higher than Youyang (P < .05). Thirty-six BLNAR isolates were identified. The MLST analysis showed 108 STs in 190 isolates, the most common of which were ST408 (11, 5.8%), ST914 (10, 5.3%), ST57 (9, 4.7%), and ST834 (6, 3.2%). Twelve STs were detected in both of the study sites, which covered 63 isolates. CONCLUSIONS All isolates in the present study were NTHi, which suggested widespread of this type in China. The BLNAR isolates were detected more frequently than before. Because high genetic diversity of NTHi isolates of H influenzae exists worldwide, it is important to continuously monitor these bacteria in the future.
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Affiliation(s)
- Qiaoli Dong
- Pediatric Intensive Care Unit, Beijing Children's Hospital, Capital Medical University, Beijing, China.,Department of Pediatrics, Affiliated Hospital of Hebei University, Baoding, China
| | - Wei Shi
- Key Laboratory of Major Diseases in Children, Beijing Key Laboratory of Pediatric Respiratory Infection Diseases, National Key Discipline of Pediatrics (Capital Medical University), National Clinical Research Center for Respiratory Diseases, National Center for Children's Health, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Xiaoping Cheng
- Youyang Hospital, People's Hospital of Chongqing Youyang County, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Changhui Chen
- Youyang Hospital, People's Hospital of Chongqing Youyang County, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Qinghong Meng
- Key Laboratory of Major Diseases in Children, Beijing Key Laboratory of Pediatric Respiratory Infection Diseases, National Key Discipline of Pediatrics (Capital Medical University), National Clinical Research Center for Respiratory Diseases, National Center for Children's Health, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Kaihu Yao
- Key Laboratory of Major Diseases in Children, Beijing Key Laboratory of Pediatric Respiratory Infection Diseases, National Key Discipline of Pediatrics (Capital Medical University), National Clinical Research Center for Respiratory Diseases, National Center for Children's Health, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Suyun Qian
- Pediatric Intensive Care Unit, Beijing Children's Hospital, Capital Medical University, Beijing, China
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8
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High diversity of invasive Haemophilus influenzae isolates in France and the emergence of resistance to third generation cephalosporins by alteration of ftsI gene. J Infect 2019; 79:7-14. [DOI: 10.1016/j.jinf.2019.05.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 04/17/2019] [Accepted: 05/10/2019] [Indexed: 01/09/2023]
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9
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Thofte O, Kaur R, Su YC, Brant M, Rudin A, Hood D, Riesbeck K. Anti-EF-Tu IgG titers increase with age and may contribute to protection against the respiratory pathogen Haemophilus influenzae. Eur J Immunol 2019; 49:490-499. [PMID: 30566236 PMCID: PMC6491980 DOI: 10.1002/eji.201847871] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Revised: 11/23/2018] [Accepted: 12/17/2018] [Indexed: 11/21/2022]
Abstract
Non‐typeable Haemophilus influenzae (NTHi) is a pathogen that commonly colonizes the nasopharynx of preschool children, causing opportunistic infections including acute otitis media (AOM). Patients suffering from chronic obstructive pulmonary disease (COPD) are persistently colonized with NTHi and occasionally suffer from exacerbations by the bacterium leading to increased morbidity. Elongation‐factor thermo unstable (EF‐Tu), a protein critical for bacterial protein synthesis, has been found to moonlight on the surface of several bacteria. Here, we show that antibodies against NTHi EF‐Tu were present in children already at 18 months of age, and that the IgG antibody titers increased with age. Children harboring NTHi in the nasopharynx also displayed significantly higher IgG concentrations. Interestingly, children suffering from AOM had significantly higher anti‐EF‐Tu IgG levels when NTHi was the causative agent. Human sera recognized mainly the central and C‐terminal part of the EF‐Tu molecule and peptide‐based epitope mapping confirmed similar binding patterns for sera from humans and immunized mice. Immunization of BALB/c and otitis‐prone Junbo (C3H/HeH) mice promoted lower infection rates in the nasopharynx and middle ear, respectively. In conclusion, our results suggest that IgG directed against NTHi EF‐Tu may play an important role in the host immune response against NTHi.
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Affiliation(s)
- Oskar Thofte
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Ravinder Kaur
- Center for Infectious Diseases and Immunology, Rochester General Hospital Research Institute, Rochester, NY
| | - Yu-Ching Su
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Marta Brant
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Anna Rudin
- Department of Immunology, Sahlgrenska University Hospital, University of Gothenburg, Gothenburg, Sweden
| | - Derek Hood
- Mammalian Genetics Unit, MRC Harwell Institute, Harwell Science & Innovation Campus, Oxfordshire, UK
| | - Kristian Riesbeck
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
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Thofte O, Su YC, Brant M, Littorin N, Duell BL, Alvarado V, Jalalvand F, Riesbeck K. EF-Tu From Non-typeable Haemophilus influenzae Is an Immunogenic Surface-Exposed Protein Targeted by Bactericidal Antibodies. Front Immunol 2018; 9:2910. [PMID: 30619274 PMCID: PMC6305414 DOI: 10.3389/fimmu.2018.02910] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2018] [Accepted: 11/27/2018] [Indexed: 01/07/2023] Open
Abstract
Non-typeable Haemophilus influenzae (NTHi), a commensal organism in pre-school children, is an opportunistic pathogen causing respiratory tract infections including acute otitis media. Adults suffering from chronic obstructive pulmonary disease (COPD) are persistently colonized by NTHi. Previous research has suggested that, in some bacterial species, the intracellular elongation factor thermo-unstable (EF-Tu) can moonlight as a surface protein upon host encounter. The aim of this study was to determine whether EF-Tu localizes to the surface of H. influenzae, and if such surface-associated EF-Tu is a target for bactericidal antibodies. Using flow cytometry, transmission immunoelectron microscopy, and epitope mapping, we demonstrated that EF-Tu is exposed at the surface of NTHi, and identified immunodominant epitopes of this protein. Rabbits immunized with whole-cell NTHi produced significantly more immunoglobulin G (IgG) directed against EF-Tu than against the NTHi outer membrane proteins D and F as revealed by enzyme-linked immunosorbent assays. Chemical cleavage of NTHi EF-Tu by cyanogen bromide (CNBr) followed by immunoblotting showed that the immunodominant epitopes were located within the central and C-terminal regions of the protein. Peptide epitope mapping by dot blot analysis further revealed four different immunodominant peptide sequences; EF-Tu41−65, EF-Tu161−185, EF-Tu221−245, and EF-Tu281−305. These epitopes were confirmed to be surface-exposed and accessible by peptide-specific antibodies in flow cytometry. We also analyzed whether antibodies raised against NTHi EF-Tu cross-react with other respiratory tract pathogens. Anti-EF-Tu IgG significantly detected EF-Tu on unencapsulated bacteria, including the Gram-negative H. parainfluenzae, H. haemolyticus, Moraxella catarrhalis and various Gram-positive Streptococci of the oral microbiome. In contrast, considerably less EF-Tu was observed at the surface of encapsulated bacteria including H. influenzae serotype b (Hib) and Streptococcus pneumoniae (e.g., serotype 3 and 4). Removal of the capsule, as exemplified by Hib RM804, resulted in increased EF-Tu surface density. Finally, anti-NTHi EF-Tu IgG promoted complement-dependent bacterial killing of NTHi and other unencapsulated Gram-negative bacteria as well as opsonophagocytosis of Gram-positive bacteria. In conclusion, our data demonstrate that NTHi EF-Tu is surface-exposed and recognized by antibodies mediating host innate immunity against NTHi in addition to other unencapsulated respiratory tract bacteria.
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Affiliation(s)
- Oskar Thofte
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Yu-Ching Su
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Marta Brant
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Nils Littorin
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Benjamin Luke Duell
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Vera Alvarado
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Farshid Jalalvand
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - Kristian Riesbeck
- Clinical Microbiology, Department of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
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Jalalvand F, Riesbeck K. Update on non-typeable Haemophilus influenzae-mediated disease and vaccine development. Expert Rev Vaccines 2018; 17:503-512. [DOI: 10.1080/14760584.2018.1484286] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Farshid Jalalvand
- Centre for Bacterial Stress Response and Persistence, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Kristian Riesbeck
- Clinical Microbiology, Department of Translational Medicine, Lund University, Malmö, Sweden
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