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Zahid A, Wilson JC, Grice ID, Peak IR. Otitis media: recent advances in otitis media vaccine development and model systems. Front Microbiol 2024; 15:1345027. [PMID: 38328427 PMCID: PMC10847372 DOI: 10.3389/fmicb.2024.1345027] [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: 11/27/2023] [Accepted: 01/08/2024] [Indexed: 02/09/2024] Open
Abstract
Otitis media is an inflammatory disorder of the middle ear caused by airways-associated bacterial or viral infections. It is one of the most common childhood infections as globally more than 80% of children are diagnosed with acute otitis media by 3 years of age and it is a common reason for doctor's visits, antibiotics prescriptions, and surgery among children. Otitis media is a multifactorial disease with various genetic, immunologic, infectious, and environmental factors predisposing children to develop ear infections. Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis are the most common culprits responsible for acute otitis media. Despite the massive global disease burden, the pathogenesis of otitis media is still unclear and requires extensive future research. Antibiotics are the preferred treatment to cure middle ear infections, however, the antimicrobial resistance rate of common middle ear pathogens has increased considerably over the years. At present, pneumococcal and influenza vaccines are administered as a preventive measure against otitis media, nevertheless, these vaccines are only beneficial in preventing carriage and/or disease caused by vaccine serotypes. Otitis media caused by non-vaccine serotype pneumococci, non-typeable H. influenza, and M. catarrhalis remain an important healthcare burden. The development of multi-species vaccines is an arduous process but is required to reduce the global burden of this disease. Many novel vaccines against S. pneumoniae, non-typeable H. influenza, and M. catarrhalis are in preclinical trials. It is anticipated that these vaccines will lower the disease burden and provide better protection against otitis media. To study disease pathology the rat, mouse, and chinchilla are commonly used to induce experimental acute otitis media to test new therapeutics, including antibiotics and vaccines. Each of these models has its advantages and disadvantages, yet there is still a need to develop an improved animal model providing a better correlated mechanistic understanding of human middle ear infections, thereby underpinning the development of more effective otitis media therapeutics. This review provides an updated summary of current vaccines against otitis media, various animal models of otitis media, their limitations, and some future insights in this field providing a springboard in the development of new animal models and novel vaccines for otitis media.
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Affiliation(s)
- Ayesha Zahid
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
| | - Jennifer C. Wilson
- School of Pharmacy and Medical Science, Griffith University, Gold Coast, QLD, Australia
| | - I. Darren Grice
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
- School of Pharmacy and Medical Science, Griffith University, Gold Coast, QLD, Australia
| | - Ian R. Peak
- Institute for Glycomics, Griffith University, Gold Coast, QLD, Australia
- School of Pharmacy and Medical Science, Griffith University, Gold Coast, QLD, Australia
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2
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Chatziparasidis G, Kantar A, Grimwood K. Pathogenesis of nontypeable Haemophilus influenzae infections in chronic suppurative lung disease. Pediatr Pulmonol 2023. [PMID: 37133207 DOI: 10.1002/ppul.26446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 04/09/2023] [Accepted: 04/23/2023] [Indexed: 05/04/2023]
Abstract
The respiratory tract antimicrobial defense system is a multilayered defense mechanism that relies upon mucociliary clearance and components of both the innate and adaptive immune systems to protect the lungs from inhaled or aspirated microorganisms. One of these potential pathogens, nontypeable Haemophilus influenzae (NTHi), adopts several, multifaceted redundant strategies to successfully colonize the lower airways and establish a persistent infection. NTHi can impair mucociliary clearance, express multiple multifunctional adhesins for various cell types within the respiratory tract and evade host defenses by surviving within and between cells, forming biofilms, increasing antigenic drift, secreting proteases and antioxidants, and by host-pathogen cross-talk, impair macrophage and neutrophil function. NTHi is recognized as an important pathogen in several chronic lower respiratory disorders, such as protracted bacterial bronchitis, bronchiectasis, cystic fibrosis, and primary ciliary dyskinesia. The persistence of NTHi in human airways, including its capacity to form biofilms, results in chronic infection and inflammation, which can ultimately injure airway wall structures. The complex nature of the molecular pathogenetic mechanisms employed by NTHi is incompletely understood but improved understanding of its pathobiology will be important for developing effective therapies and vaccines, especially given the marked genetic heterogeneity of NTHi and its possession of phase-variable genes. Currently, no vaccine candidates are ready for large phase III clinical trials.
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Affiliation(s)
- Grigorios Chatziparasidis
- Paediatric Respiratory Unit, IASO Hospital, Larissa, Thessaly, Greece
- Faculty of Nursing, Thessaly University, Larissa, Greece
| | - Ahmad Kantar
- Pediatric Asthma and Cough Centre, Instituti Ospedalieri Bergamaschi, Bergamo, Italy
- Vita-Salute San Raffaele University, Milan, Italy
| | - Keith Grimwood
- School of Medicine and Dentistry, and Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
- Departments of Infectious Disease and Paediatrics, Gold Coast Health, Southport, Queensland, Australia
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3
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Phillips ZN, Jennison AV, Whitby PW, Stull TL, Staples M, Atack JM. Examination of phase-variable haemoglobin-haptoglobin binding proteins in Non-typeable Haemophilus influenzae reveals a diverse distribution of multiple variants. FEMS Microbiol Lett 2022; 369:6648706. [PMID: 35867873 PMCID: PMC9341677 DOI: 10.1093/femsle/fnac064] [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] [Received: 03/14/2022] [Revised: 06/14/2022] [Accepted: 07/20/2022] [Indexed: 11/25/2022] Open
Abstract
Non-typeable Haemophilus influenzae (NTHi) is a major human pathogen for which there is no globally licensed vaccine. NTHi has a strict growth requirement for iron and encodes several systems to scavenge elemental iron and heme from the host. An effective NTHi vaccine would target conserved, essential surface factors, such as those involved in iron acquisition. Haemoglobin–haptoglobin binding proteins (Hgps) are iron-uptake proteins localized on the outer-membrane of NTHi. If the Hgps are to be included as components of a rationally designed subunit vaccine against NTHi, it is important to understand their prevalence and diversity. Following analysis of all available Hgp sequences, we propose a standardized grouping method for Hgps, and demonstrate increased diversity of these proteins than previously determined. This analysis demonstrated that genes encoding variants HgpB and HgpC are present in all strains examined, and almost 40% of strains had a duplicate, nonidentical hgpB gene. Hgps are also phase-variably expressed; the encoding genes contain a CCAA(n) simple DNA sequence repeat tract, resulting in biphasic ON–OFF switching of expression. Examination of the ON–OFF state of hgpB and hgpC genes in a collection of invasive NTHi isolates demonstrated that 58% of isolates had at least one of hgpB or hgpC expressed (ON). Varying expression of a diverse repertoire of hgp genes would provide strains a method of evading an immune response while maintaining the ability to acquire iron via heme. Structural analysis of Hgps also revealed high sequence variability at the sites predicted to be surface exposed, demonstrating a further mechanism to evade the immune system—through varying the surface, immune-exposed regions of the membrane anchored protein. This information will direct and inform the choice of candidates to include in a vaccine against NTHi.
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Affiliation(s)
- Zachary N Phillips
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Amy V Jennison
- Queensland Department of Health, Public Health Microbiology, Forensic and Scientific Services, Brisbane, Queensland, Australia
| | | | | | - Megan Staples
- Queensland Department of Health, Public Health Microbiology, Forensic and Scientific Services, Brisbane, Queensland, Australia
| | - John M Atack
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia.,School of Environment and Science, Griffith University, Gold Coast, Queensland, Australia
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Whitby PW, Morton DJ, Mussa HJ, Mirea L, Stull TL. A bacterial vaccine polypeptide protective against nontypable Haemophilus influenzae. Vaccine 2020; 38:2960-2970. [PMID: 32111525 DOI: 10.1016/j.vaccine.2020.02.054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 02/07/2020] [Accepted: 02/18/2020] [Indexed: 02/08/2023]
Abstract
Nontypeable strains of Haemophilus influenzae (NTHi) are one of the most common cause of otitis media and the most frequent infection associated with exacerbations of chronic obstructive pulmonary disease; there is currently no vaccine in the U.S. to prevent NTHi. Using bioinformatics and structural vaccinology, we previously identified several NTHi species-conserved and sequence-conserved peptides that mediate passive protection in the rat model of infection. Using these, and similar peptides, we designed Hi Poly 1, a Bacterial Vaccine Polypeptide, comprising 9 unique peptides from 6 different surface proteins. Recombinant Hi Poly 1 was purified by affinity chromatography. Forty chinchillas were immunized three times with 200 µg of Hi Poly 1 with alum adjuvant; similarly, 41 controls were immunized with adjuvant alone. The average Log2 IgG titer among immunized animals was 17.04, and IgG antibodies against each component peptide were detected. In the infant rat model, antisera from immunized chinchillas provided significant passive protection compared to PBS (p = 0.01) and pre-immune sera (p = 0.03). In the established chinchilla model of NTHi otitis media, the vaccinated group cleared infection faster than the control group as indicated by significantly decreased positive findings on video-otoscopy (p < 0.0001) and tympanometry (p = 0.0002) on day 7, and for middle ear fluid obtained by aspiration (p = 0.0001) on day 10 post-infection. Using 12 representative NTHi strains in a Live-Cell ELISA, greater antibody binding to each strain was detected with post Hi Poly 1 than the pre-immune chinchilla antisera. The data from this proof-of-principle study demonstrate the effectiveness of Hi Poly 1 against the NTHi in two relevant preclinical models of bacteremia and otitis media as well as surface antibody binding across the species. The Bacterial Vaccine Polypeptide approach to a vaccine against NTHi also serves as a paradigm for development of similar vaccines to protect against other bacteria.
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Affiliation(s)
- Paul W Whitby
- Department of Child Health, University of Arizona College of Medicine-Phoenix, United States; Phoenix Childrens Hospital, Phoenix, United States.
| | - Daniel J Morton
- Department of Child Health, University of Arizona College of Medicine-Phoenix, United States; Phoenix Childrens Hospital, Phoenix, United States
| | - Huda J Mussa
- Department of Child Health, University of Arizona College of Medicine-Phoenix, United States; Phoenix Childrens Hospital, Phoenix, United States
| | - Lucia Mirea
- Department of Child Health, University of Arizona College of Medicine-Phoenix, United States; Phoenix Childrens Hospital, Phoenix, United States
| | - Terrence L Stull
- Department of Child Health, University of Arizona College of Medicine-Phoenix, United States; Phoenix Childrens Hospital, Phoenix, United States
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Thornton RB, Hakansson A, Hood DW, Nokso-Koivisto J, Preciado D, Riesbeck K, Richmond PC, Su YC, Swords WE, Brockman KL. Panel 7 - Pathogenesis of otitis media - a review of the literature between 2015 and 2019. Int J Pediatr Otorhinolaryngol 2020; 130 Suppl 1:109838. [PMID: 31879085 PMCID: PMC7062565 DOI: 10.1016/j.ijporl.2019.109838] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE To perform a comprehensive review of the literature from July 2015 to June 2019 on the pathogenesis of otitis media. Bacteria, viruses and the role of the microbiome as well as the host response are discussed. Directions for future research are also suggested. DATA SOURCES PubMed database of the National Library of Medicine. REVIEW METHODS PubMed was searched for any papers pertaining to OM pathogenesis between July 2015 and June 2019. If in English, abstracts were assessed individually for their relevance and included in the report. Members of the panel drafted the report based on these searches and on new data presented at the 20th International Symposium on Recent Advances in Otitis Media. CONCLUSIONS The main themes that arose in OM pathogenesis were around the need for symptomatic viral infections to develop disease. Different populations potentially having different mechanisms of pathogenesis. Novel bacterial otopathogens are emerging and need to be monitored. Animal models need to continue to be developed and used to understand disease pathogenesis. IMPLICATIONS FOR PRACTICE The findings in the pathogenesis panel have several implications for both research and clinical practice. The most urgent areas appear to be to continue monitoring the emergence of novel otopathogens, and the need to develop prevention and preventative therapies that do not rely on antibiotics and protect against the development of the initial OM episode.
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Affiliation(s)
- R B Thornton
- Wesfarmers Centre of Vaccines and Infectious Diseases, Telethon Kids Institute, Perth, Western Australia, Australia; School of Biomedical Sciences, Faculty Health and Medical Science, University of Western Australia, Perth, Western Australia, Australia
| | - A Hakansson
- Experimental Infection Medicine, Dept. of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - D W Hood
- MRC Harwell Institute, Mammalian Genetics Unit, Harwell Campus, Oxfordshire, OX11 0RD, UK
| | - J Nokso-Koivisto
- Department of Otorhinolaryngology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - D Preciado
- Sheikh Zayed Center for Pediatric Surgical Innovation, Children's National Health System, Washington, DC, USA; Division of Pediatric Otolaryngology, Children's National Health System, Washington, DC, USA
| | - K Riesbeck
- Clinical Microbiology, Dept. of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - P C Richmond
- School of Medicine, Division of Paediatrics, Faculty Health and Medical Science, University of Western Australia, Perth, Western Australia, Australia; Perth Children's Hospital, Perth, Western Australia, Australia
| | - Y C Su
- Clinical Microbiology, Dept. of Translational Medicine, Faculty of Medicine, Lund University, Malmö, Sweden
| | - W E Swords
- Department of Microbiology and Immunology, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - K L Brockman
- Department of Microbiology & Immunology, Medical College of Wisconsin, Milwaukee, WI, USA.
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Alderson MR, Murphy T, Pelton SI, Novotny LA, Hammitt LL, Kurabi A, Li JD, Thornton RB, Kirkham LAS. Panel 8: Vaccines and immunology. Int J Pediatr Otorhinolaryngol 2020; 130 Suppl 1:109839. [PMID: 31948716 PMCID: PMC7153269 DOI: 10.1016/j.ijporl.2019.109839] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To review and highlight significant advances made towards vaccine development and understanding of the immunology of otitis media (OM) since the 19th International Symposium on Recent Advances in Otitis Media (ISOM) in 2015, as well as identify future research directions and knowledge gaps. DATA SOURCES PubMed database, National Library of Medicine. REVIEW METHODS Key topics were assigned to each panel member for detailed review. Draft reviews were collated, circulated, and thoroughly discussed when the panel met at the 20th ISOM in June 2019. The final manuscript was prepared with input from all panel members. CONCLUSIONS Since 2015 there have been a number of studies assessing the impact of licensed pneumococcal vaccines on OM. While these studies have confirmed that these vaccines are effective in preventing carriage and/or disease caused by vaccine serotypes, OM caused by non-vaccine serotype pneumococci and other otopathogens remains a significant health care burden globally. Development of multi-species vaccines is challenging but essential to reducing the global burden of OM. Influenza vaccination has been shown to prevent acute OM, and with novel vaccines against nontypeable Haemophilus influenzae (NTHi), Moraxella catarrhalis and Respiratory Syncytial Virus (RSV) in clinical trials, the potential to significantly prevent OM is within reach. Research into alternative vaccine delivery strategies has demonstrated the power of maternal and mucosal vaccination for OM prevention. Future OM vaccine trials must include molecular diagnostics of middle ear effusion, for detection of viruses and bacteria that are persisting in biofilms and to enable accurate assessment of vaccine impact on OM etiology. Understanding population differences in natural and vaccine-induced immune responses to otopathogens is also important for development of the most effective OM vaccines. Improved understanding of the interaction between otopathogens will also advance development of effective therapies and encourage the assessment of the indirect benefits of vaccination. IMPLICATIONS FOR PRACTICE While NTHi and M. catarrhalis are the predominant otopathogens, funding opportunities to drive vaccine development for these species are limited due to a focus on prevention of childhood mortality rather than morbidity. Delivery of a comprehensive report on the high financial and social costs of OM, including the potential for OM vaccines to reduce antibiotic use and subsequent development of antimicrobial resistance (AMR), would likely assist in engaging stakeholders to recognize the value of prevention of OM and increase support for efforts on OM vaccine development. Vaccine trials with OM prevention as a clinical end-point are challenging, however a focus on developing assays that measure functional correlates of protection would facilitate OM vaccine development.
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Affiliation(s)
| | - Tim Murphy
- Clinical and Translational Research Center, University at Buffalo, The State University of New York, Buffalo, NY, USA
| | - Stephen I Pelton
- Boston University School of Public Health, Boston University, Boston, MA, USA
| | - Laura A Novotny
- The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Laura L Hammitt
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Arwa Kurabi
- Division of Otolaryngology, Department of Surgery, University of California, San Diego, CA, USA
| | - Jian-Dong Li
- Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences, Georgia State University, GA, USA
| | - Ruth B Thornton
- School of Biomedical Sciences, University of Western Australia, Australia and Wesfarmers Centre for Vaccines and Infectious Diseases Research, Telethon Kids Institute, Perth, Australia
| | - Lea-Ann S Kirkham
- Wesfarmers Centre for Vaccines and Infectious Diseases Research, Telethon Kids Institute, Australia and Centre for Child Health Research, University of Western Australia, Perth, Australia
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Gisselsson-Solén M, Tähtinen PA, Ryan AF, Mulay A, Kariya S, Schilder AG, Valdez TA, Brown S, Nolan RM, Hermansson A, van Ingen G, Marom T. Panel 1: Biotechnology, biomedical engineering and new models of otitis media. Int J Pediatr Otorhinolaryngol 2020; 130 Suppl 1:109833. [PMID: 31901291 PMCID: PMC7176743 DOI: 10.1016/j.ijporl.2019.109833] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To summarize recently published key articles on the topics of biomedical engineering, biotechnology and new models in relation to otitis media (OM). DATA SOURCES Electronic databases: PubMed, Ovid Medline, Cochrane Library and Clinical Evidence (BMJ Publishing). REVIEW METHODS Articles on biomedical engineering, biotechnology, material science, mechanical and animal models in OM published between May 2015 and May 2019 were identified and subjected to review. A total of 132 articles were ultimately included. RESULTS New imaging technologies for the tympanic membrane (TM) and the middle ear cavity are being developed to assess TM thickness, identify biofilms and differentiate types of middle ear effusions. Artificial intelligence (AI) has been applied to train software programs to diagnose OM with a high degree of certainty. Genetically modified mice models for OM have further investigated what predisposes some individuals to OM and consequent hearing loss. New vaccine candidates protecting against major otopathogens are being explored and developed, especially combined vaccines, targeting more than one pathogen. Transcutaneous vaccination against non-typeable Haemophilus influenzae has been successfully tried in a chinchilla model. In terms of treatment, novel technologies for trans-tympanic drug delivery are entering the clinical domain. Various growth factors and grafting materials aimed at improving healing of TM perforations show promising results in animal models. CONCLUSION New technologies and AI applications to improve the diagnosis of OM have shown promise in pre-clinical models and are gradually entering the clinical domain. So are novel vaccines and drug delivery approaches that may allow local treatment of OM. IMPLICATIONS FOR PRACTICE New diagnostic methods, potential vaccine candidates and the novel trans-tympanic drug delivery show promising results, but are not yet adapted to clinical use.
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Affiliation(s)
- Marie Gisselsson-Solén
- Department of Clinical Sciences, Division of Otorhinolaryngology, Head and Neck Surgery, Lund University Hospital, Lund, Sweden
| | - Paula A. Tähtinen
- Department of Pediatrics and Adolescent Medicine, Turku University Hospital and University of Turku, Turku, Finland
| | - Allen F. Ryan
- Division of Otolaryngology, Department of Surgery, University of California, San Diego, La Jolla, CA, USA,San Diego Veterans Affairs Healthcare System, Research Department, San Diego, CA, USA
| | - Apoorva Mulay
- The Stripp Lab, Pulmonary Department, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - Shin Kariya
- Department of Otolaryngology-Head and Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Anne G.M. Schilder
- EvidENT, Ear Institute, University College London, London, UK,National Institute for Health Research University College London Biomedical Research Centre, London, UK,Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Tulio A. Valdez
- Department of Otolaryngology Head & Neck Surgery, Stanford University, Palo Alto, CA, USA
| | - Steve Brown
- MRC Harwell Institute, Mammalian Genetics Unit, Harwell Campus, Oxfordshire, UK
| | | | - Ann Hermansson
- Department of Clinical Sciences, Division of Otorhinolaryngology, Head and Neck Surgery, Lund University Hospital, Lund, Sweden
| | - Gijs van Ingen
- Department of Otolaryngology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Tal Marom
- Department of Otolaryngology-Head and Neck Surgery, Samson Assuta Ashdod University Hospital, Faculty of Health Sciences Ben Gurion University, Ashdod, Israel.
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Price EP, Harris TM, Spargo J, Nosworthy E, Beissbarth J, Chang AB, Smith-Vaughan HC, Sarovich DS. Simultaneous identification of Haemophilus influenzae and Haemophilus haemolyticus using real-time PCR. Future Microbiol 2017; 12:585-593. [PMID: 28604066 DOI: 10.2217/fmb-2016-0215] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
AIM To design a highly specific and sensitive multiplex real-time PCR assay for the differentiation of the pathogen Haemophilus influenzae from its nonpathogenic near-neighbor Haemophilus haemolyticus. MATERIALS & METHODS A comparison of 380 Haemophilus spp. genomes was used to identify loci specific for each species. Novel PCR assays targeting H. haemolyticus (hypD) and H. influenzae (siaT) were designed. RESULTS & DISCUSSION PCR screening across 143 isolates demonstrated 100% specificity for hypD and siaT. These two assays were multiplexed with the recently described fucP assay for further differentiation among H. influenzae. CONCLUSION The triplex assay provides rapid, unambiguous, sensitive and highly specific genotyping results for the simultaneous detection of hypD and siaT, including fucose-positive H. influenzae (fucP), in a single PCR.
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Affiliation(s)
- Erin P Price
- Child Health Division, Menzies School of Health Research, Darwin, NT, Australia.,Centre for Animal Health Innovation, Faculty of Science, Health, Education & Engineering, University of the Sunshine Coast, Sippy Downs, QLD, Australia
| | - Tegan M Harris
- Child Health Division, Menzies School of Health Research, Darwin, NT, Australia
| | - Jessie Spargo
- Child Health Division, Menzies School of Health Research, Darwin, NT, Australia
| | - Elizabeth Nosworthy
- Child Health Division, Menzies School of Health Research, Darwin, NT, Australia
| | - Jemima Beissbarth
- Child Health Division, Menzies School of Health Research, Darwin, NT, Australia
| | - Anne B Chang
- Child Health Division, Menzies School of Health Research, Darwin, NT, Australia
| | | | - Derek S Sarovich
- Child Health Division, Menzies School of Health Research, Darwin, NT, Australia.,Centre for Animal Health Innovation, Faculty of Science, Health, Education & Engineering, University of the Sunshine Coast, Sippy Downs, QLD, Australia
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Cerquetti M, Giufrè M. Why we need a vaccine for non-typeable Haemophilus influenzae. Hum Vaccin Immunother 2016; 12:2357-61. [PMID: 27171854 DOI: 10.1080/21645515.2016.1174354] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Nontypeable Haemophilus influenzae (NTHi) is increasingly recognized as emerging pathogen. The routine immunization of infants with conjugated vaccines against H. influenzae type b (Hib) has greatly reduced the incidence of invasive Hib disease; however a marked change in the predominant invasive serotype from Hib to NTHi has occurred. Localized infections where the role of H. influenzae is important, such as otitis media in children and acute exacerbations in chronic obstructive pulmonary disease (COPD) in adults, are almost exclusively associated with NTHi isolates. The implementation of pneumococcal conjugate vaccines has resulted in changes in frequency of nasopharynx colonizing pathogens with an increase of NTHi, although this data is yet under debate. An effective vaccine against NTHi is not currently available. The major challenge in developing a successful vaccine is the intrinsic heterogeneity of NTHi. H. influenzae protein D is used as carrier protein in the licensed 10-valent pneumococcal conjugate vaccine (Synflorix, GlaxoSmithKline), but no robust evidences for protective efficacy against NTHi otitis have been until now obtained. Several other vaccine candidates are under investigations and we hope that significant advancements in vaccine development will be achieved in the next future. Genome-based vaccine strategy might provide an additional useful tool for discovering further vaccine antigens.
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Affiliation(s)
- Marina Cerquetti
- a Department of Infectious , Parasitic and Immune-Mediated Diseases , Istituto Superiore di Sanità , Rome , Italy
| | - Maria Giufrè
- a Department of Infectious , Parasitic and Immune-Mediated Diseases , Istituto Superiore di Sanità , Rome , Italy
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