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Ma Y, Zhao Y, Chen R, Sun W, Zhang Y, Qiao H, Chang Y, Kang S, Zhang Y. Mucosal immunity of mannose-modified chitosan microspheres loaded with the nontyepable Haemophilus influenzae outer membrane protein P6 in BALB/c mice. PLoS One 2022; 17:e0269153. [PMID: 35687548 PMCID: PMC9187061 DOI: 10.1371/journal.pone.0269153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 05/16/2022] [Indexed: 11/18/2022] Open
Abstract
Nontypeable Haemophilus influenzae (NTHi) is a common opportunistic pathogen that colonizes the nasopharynx. NTHi infections result in enormous global morbidity in two clinical settings: otitis media in children and acute exacerbation of chronic obstructive pulmonary disease (COPD) in adults. Thus, there is an urgent need to design and develop effective vaccines to prevent morbidity and reduce antibiotic use. The NTHi outer membrane protein P6, a potential vaccine candidate, is highly conserved and effectively induces protective immunity. Here, to enhance mucosal immune responses, P6-loaded mannose-modified chitosan (MC) microspheres (P6-MCMs) were developed for mucosal delivery. MC (18.75%) was synthesized by the reductive amination reaction method using sodium cyanoborohydride (NaBH3CN), and P6-MCMs with an average size of 590.4±16.2 nm were successfully prepared via the tripolyphosphate (TPP) ionotropic gelation process. After intranasal immunization with P6-MCMs, evaluation of humoral immune responses indicated that P6-MCMs enhance both systemic and mucosal immune responses. Evaluation of cellular immune responses indicated that P6-MCMs enhance cellular immunity and trigger a mixed Th1/Th2-type immune response. Importantly, P6-MCMs also trigger a Th17-type immune response. They are effective in promoting lymphocyte proliferation and differentiation without toxicity in vitro. The results also demonstrate that P6-MCMs can effectively induce MHC class I- and II-restricted cross-presentation, promoting CD4+-mediated Th immune responses and CD8+-mediated cytotoxic T lymphocyte (CTL) immune responses. Evaluation of protective immunity indicated that immunization with P6-MCMs can reduce inflammation in the nasal mucosa and the lung and prevent NTHi infection. In conclusion, MCMs are a promising adjuvant-delivery system for vaccines against NTHi.
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Affiliation(s)
- Yushuai Ma
- Institute of Pathogen Biology and Immunology, Hebei North University, Zhangjiakou, Hebei Province, China
| | - Ying Zhao
- Institute of Pathogen Biology and Immunology, Hebei North University, Zhangjiakou, Hebei Province, China
| | - Rui Chen
- Institute of Pathogen Biology and Immunology, Hebei North University, Zhangjiakou, Hebei Province, China
| | - Wanru Sun
- Institute of Pathogen Biology and Immunology, Hebei North University, Zhangjiakou, Hebei Province, China
| | - Yanxia Zhang
- Department of Microbiology, Hebei North University, Zhangjiakou, Hebei Province, China
| | - Haixia Qiao
- Department of Microbiology, Hebei North University, Zhangjiakou, Hebei Province, China
| | - Yueli Chang
- Department of Microbiology, Hebei North University, Zhangjiakou, Hebei Province, China
| | - Shaoping Kang
- Department of Immunology, Hebei North University, Zhangjiakou, Hebei Province, China
| | - Yutuo Zhang
- Department of Microbiology, Hebei North University, Zhangjiakou, Hebei Province, China
- * E-mail:
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Kc R, O'Toole RF. Draft genome sequence of a nontypeable Haemophilus influenzae strain used in the study of human respiratory infection. BMC Res Notes 2021; 14:123. [PMID: 33794985 PMCID: PMC8015102 DOI: 10.1186/s13104-021-05528-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 03/13/2021] [Indexed: 11/21/2022] Open
Abstract
Objectives Nontypeable Haemophilus influenzae (NTHi) is an important human respiratory bacterium that can cause a range of diseases including sinusitis, otitis media, conjunctivitis, pneumonia as well as acute exacerbations of chronic obstructive pulmonary disease (COPD). A number of studies have used NTHi clinical isolate RHH-3 as a laboratory strain for experimentation examining the effect of cigarette smoke and more recently, biomass smoke, on the susceptibility and response of cells lining the respiratory tract to infection. Therefore, definition of the genome content of RHH-3 is required to fully elucidate human-NTHi interactions associated with initial infection and subsequent development of respiratory disease. Data description Here, we present the draft genome sequence of NTHi RHH-3 collected from the sputum of a patient at the Royal Hobart Hospital, Tasmania, Australia. The assembled genome size was 1,839,376 bp consisting of 61 contigs (> 500 bp), with a G+C content of 38.1%. This draft genome data can be accessed at DDBJ/ENA/GenBank under the accession number JADPRR000000000.
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Affiliation(s)
- Rajendra Kc
- Menzies Institute for Medical Research, University of Tasmania, Tasmania, 7005, Australia
| | - Ronan F O'Toole
- Department of Pharmacy and Biomedical Sciences, School of Molecular Sciences, College of Science, Health and Engineering, La Trobe University, Victoria, 3690, Australia.
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Ween MP, Whittall JJ, Hamon R, Reynolds PN, Hodge SJ. Phagocytosis and Inflammation: Exploring the effects of the components of E-cigarette vapor on macrophages. Physiol Rep 2018; 5:5/16/e13370. [PMID: 28867672 PMCID: PMC5582261 DOI: 10.14814/phy2.13370] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2017] [Revised: 06/26/2017] [Accepted: 06/28/2017] [Indexed: 01/24/2023] Open
Abstract
E‐cigarettes are perceived as harmless; however, evidence of their safety is lacking. New data suggests E‐cigarettes discharge a range of compounds capable of physiological damage to users. We previously established that cigarette smoke caused defective alveolar macrophage phagocytosis. The present study compared the effect E‐cigarette of components; E‐liquid flavors, nicotine, vegetable glycerine, and propylene glycol on phagocytosis, proinflammatory cytokine secretion, and phagocytic recognition molecule expression using differentiated THP‐1 macrophages. Similar to CSE, phagocytosis of NTHi bacteria was significantly decreased by E‐liquid flavoring (11.65–15.75%) versus control (27.01%). Nicotine also decreased phagocytosis (15.26%). E‐liquid, nicotine, and E‐liquid+ nicotine reduced phagocytic recognition molecules; SR‐A1 and TLR‐2. IL‐8 secretion increased with flavor and nicotine, while TNFα, IL‐1β, IL‐6, MIP‐1α, MIP‐1β, and MCP‐1 decreased after exposure to most flavors and nicotine. PG, VG, or PG:VG mix also induced a decrease in MIP‐1α and MIP‐1β. We conclude that E‐cigarettes can cause macrophage phagocytic dysfunction, expression of phagocytic recognition receptors and cytokine secretion pathways. As such, E‐cigarettes should be treated with caution by users, especially those who are nonsmokers.
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Affiliation(s)
- Miranda P Ween
- Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, Australia .,School of Medicine, University of Adelaide, Adelaide, Australia
| | - Jonathan J Whittall
- Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, Australia.,School of Medicine, University of Adelaide, Adelaide, Australia
| | - Rhys Hamon
- Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, Australia.,School of Medicine, University of Adelaide, Adelaide, Australia
| | - Paul N Reynolds
- Department of Thoracic Medicine, Royal Adelaide Hospital, Adelaide, Australia.,School of Medicine, University of Adelaide, Adelaide, Australia
| | - Sandra J Hodge
- School of Medicine, University of Adelaide, Adelaide, Australia
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Kaneko M, Bando Y, Fujita T, Hirose Y, Suganuma E, Ishii M, Takahashi T. Encapsulated pleural effusion due to Haemophilus influenzae biotype II in a child with trisomy 21: A case report and literature review. IDCases 2017; 10:93-96. [PMID: 29062709 PMCID: PMC5645171 DOI: 10.1016/j.idcr.2017.09.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 09/23/2017] [Accepted: 09/25/2017] [Indexed: 11/19/2022] Open
Abstract
This is the second case report of pediatric encapsulated pleural effusion (EPE) due to Haemophilus influenzae. We represent typical images of chest X-P, CT, echography to find the EPE. Nontypeable H. influenzae was isolated from the throat after the discharge.
Haemophilus influenzae (Hi) can colonize in the upper respiratory tract and cause severe pulmonary infections, especially among immunocompromised children. Herein, we report a case of left encapsulated pleural effusion (EPE) due to Hi in a 24-month-old girl with trisomy 21. She was already vaccinated against Hi type b. The Hi biotype II was isolated from both the blood and aspirated sputum obtained upon admission. Ampicillin/sulbactam 180 mg/kg/day was administered intravenously for 34 days with oxygen supplementation for 4 days. She clinically recovered without undergoing thoracic drainage. One month after discharge, the girl developed acute otitis media, and the throat swab was cultured. Nontypeable Hi with the same biotype II was isolated, and the infection was controlled by administering antimicrobials. In this report, a literature review regarding the EPE due to Hi in children is also summarized. Pediatric clinicians should be aware of the possibility of Hi-related EPE because of its rapid progression, although it is rare in clinical settings. In addition, they need to consider the possibility of repetitive respiratory infections with Hi in a child with trisomy 21.
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Affiliation(s)
- Masanori Kaneko
- Department of Pediatrics, Kitasato University Medical Center, 6-100 Arai, Kitamoto, Saitama 364-8501, Japan
| | - Yuki Bando
- Department of Pediatrics, Kitasato University Medical Center, 6-100 Arai, Kitamoto, Saitama 364-8501, Japan
- Department of Infection Control and Prevention, Kitasato University Medical Center, 6-100 Arai, Kitamoto, Saitama 364-8501, Japan
- Corresponding author at: Department of Pediatrics, Kitasato University Medical Center, 6-100 Arai, Kitamoto, Saitama 364-8501, Japan.Department of PediatricsKitasato University Medical Center6-100 AraiKitamotoSaitama364-8501Japan
| | - Tomohiro Fujita
- Department of Clinical Laboratory, Kitasato University Medical Center, 6-100 Arai, Kitamoto, Saitama 364-8501, Japan
| | - Yoneji Hirose
- Department of Clinical Laboratory, Kitasato University Medical Center, 6-100 Arai, Kitamoto, Saitama 364-8501, Japan
| | - Eisuke Suganuma
- Division of Infectious Diseases and Immunology, Saitama Children’s Medical Center, 1-2 Shintoshin, Chuuou-ku, Saitama, Saitama 330-8777, Japan
| | - Masahiro Ishii
- Department of Pediatrics, Kitasato University School of Medicine, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa 252-0374, Japan
| | - Takashi Takahashi
- Laboratory of Infectious Diseases, Kitasato Institute for Life Sciences & Graduate School of Infection Control Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
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Iwata S, Kawamura N, Kuroki H, Tokoeda Y, Miyazu M, Iwai A, Oishi T, Sato T, Suyama A, François N, Shafi F, Ruiz-Guiñazú J, Borys D. Immunogenicity and safety of the 10-valent pneumococcal nontypeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) co-administered with DTPa vaccine in Japanese children: A randomized, controlled study. Hum Vaccin Immunother 2016; 11:826-37. [PMID: 25830489 PMCID: PMC4514407 DOI: 10.1080/21645515.2015.1012019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
This phase III, randomized, open-label, multicenter study (NCT01027845) conducted in Japan assessed the immunogenicity, safety, and reactogenicity of 10-valent pneumococcal nontypeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV, given intramuscularly) co-administered with diphtheria-tetanus-acellular pertussis vaccine (DTPa, given subcutaneously). Infants (N=360 ) were randomized (2:1) to receive either PHiD-CV and DTPa (PHiD-CV group) or DTPa alone (control group) as 3-dose primary vaccination (3–4–5 months of age) and booster vaccination (17–19 months of age). Immune responses were measured before and one month after primary/booster vaccination and adverse events (AEs) were recorded. Post-primary immune responses were non-inferior to those in pivotal/efficacy European or Latin American pneumococcal protein D-conjugate vaccine studies. For each PHiD-CV serotype, at least 92.6% of infants post-primary vaccination and at least 97.7% of children post-booster had pneumococcal antibody concentrations ≥0.2 μg/ml, and at least 95.4% post-primary and at least 98.1% post-booster had opsonophagocytic activity (OPA) titers ≥8 . Geometric mean antibody concentrations and OPA titers (except OPA titer for 6B) were higher post-booster than post-priming for each serotype. All PHiD-CV-vaccinated children had anti-protein D antibody concentrations ≥100 EL.U/ml one month post-primary/booster vaccination and all were seroprotected/seropositive against each DTPa antigen. Redness and irritability were the most common solicited AEs in both groups. Incidences of unsolicited AEs were comparable between groups. Serious AEs were reported for 47 children (28 in PHiD-CV group); none were assessed as vaccine-related. In conclusion, PHiD-CV induced robust immune responses and was well tolerated when co-administered with DTPa in a 3-dose priming plus booster regimen to Japanese children.
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Key Words
- 7vCRM, 7-valent pneumococcal CRM-conjugate vaccine
- AE, adverse event
- AOM, acute otitis media
- ATP, according-to-protocol
- CAP, community-acquired pneumonia
- CI, confidence interval
- COMPAS, Clinical Otitis Media and PneumoniA Study
- DTPa, diphtheria-tetanus-acellular pertussis
- ELISA, enzyme-linked immunosorbent assay
- GMC, geometric mean concentration
- GMT, geometric mean titer
- HBV, hepatitis B virus
- Hib, Haemophilus influenzae type b
- IPD, invasive pneumococcal disease
- Japan
- NTHi, nontypeable Haemophilus influenzae
- OPA, opsonophagocytic activity
- PCV, pneumococcal conjugate vaccine
- PHiD-CV, 10-valent pneumococcal nontypeable Haemophilus influenzae protein D conjugate vaccine
- POET, Pneumococcal Otitis Efficacy Trial
- SAE, serious adverse event
- SAS, Statistical Analysis System
- SDD, SAS Drug and Development
- WHO, World Health Organization
- children
- co-administration
- immunogenicity
- pneumococcal conjugate vaccine
- safety
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Affiliation(s)
- Satoshi Iwata
- a Department of Infectious Diseases ; School of Medicine; Keio University ; Shinjuku-ku , Tokyo , Japan
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Baba H, Sato Y, Toyonaga Y, Hanaki H, Sunakawa K. Nationwide survey of the development of drug resistance in the pediatric field in 2007, 2010, and 2012: drug sensitivity of Haemophilus influenzae serotype b strain in Japan. J Infect Chemother 2014; 21:277-83. [PMID: 25618776 DOI: 10.1016/j.jiac.2014.12.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Revised: 12/04/2014] [Accepted: 12/13/2014] [Indexed: 11/29/2022]
Abstract
Based on the results of surveillance in the pediatric field conducted in 2007, 2010, and 2012, we examined the frequency of Haemophilus influenzae serotype b (Hib) strains, the susceptibility for Hib strains to various types of antimicrobial agent, and the relations to patients' background factors. Among all of Haemophilus influenzae, the frequency of Hib strains was 3.6% (14/386 strains) in 2007, 4.8% (23/484 strains) in 2010, 1.2% (5/411 strains) in 2012, and decreasing in 2012. Hib strains were isolated in patients with the following infections: nine patients with respiratory tract infections (upper respiratory tract infection, bronchitis, and pneumonia), three patients with sepsis, one patient with meningitis, and one patient with purulent inflammation of a tendon sheath in 2007; 11 patients with respiratory tract infections (upper respiratory tract infection, bronchitis, and pneumonia), four patients with sepsis, and eight patients with meningitis in 2010, demonstrating a relatively high frequency in patients with invasive infections. However, in 2012, Hib strains were isolated in only four patients with respiratory tract infections (upper respiratory tract infection) and one patient with bronchial asthma. Evaluation of background factors with pediatric patients in whom Hib strains were isolated showed that approximately 70% were male; majority was children under three years of age; and higher detection rates were also related to the background of patients who were attendant to daycare center, had siblings, had received no antimicrobial agents within the previous one month before collecting specimens. Throughout the surveillance between 2007 and 2012, antimicrobial agents with all phases' MICs ≤ 1 μg/mL were cefditoren, cefcapene, and cefteram in the oral β-lactams; tazobactam/piperacillin, ceftriaxone, cefotaxime, and meropenem in the injectable β-lactams; azithromycin in the macrolide; and levofloxacin in the quinolone. After 2010, MIC ranges were evaluated for tebipenem in the oral β-lactam (≤ 0.063-0.25 μg/mL), doripenem in the injectable β-lactam (≤ 0.063-0.5 μg/mL), and tosufloxacin in the quinolone (≤ 0.063 μg/mL). Throughout the surveillance, Hib strains were highly susceptible to the above mentioned antimicrobial agents, and there was no significant change in the susceptibility.
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Affiliation(s)
- Hiroaki Baba
- Fuji Heavy Industries Health Insurance Society, Ota Memorial Hospital, Ota, Gunma, Japan; The Drug-Resistant Pathogen Surveillance Group in Pediatric Infectious Disease, Japan.
| | - Yoshitake Sato
- Fuji Heavy Industries Health Insurance Society, Ota Memorial Hospital, Ota, Gunma, Japan; The Drug-Resistant Pathogen Surveillance Group in Pediatric Infectious Disease, Japan
| | - Yoshikiyo Toyonaga
- Saitama Sekishinkai Hospital, Sayama, Saitama, Japan; The Drug-Resistant Pathogen Surveillance Group in Pediatric Infectious Disease, Japan
| | - Hideaki Hanaki
- The Kitasato Institute, Kitasato University Research Center for Anti-infectious Drugs, Tokyo, Japan
| | - Keisuke Sunakawa
- The Kitasato Institute, Kitasato University Research Organization for Infection Control Sciences, Tokyo, Japan; The Drug-Resistant Pathogen Surveillance Group in Pediatric Infectious Disease, Japan
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Shiragami M, Mizukami A, Leeuwenkamp O, Mrkvan T, Delgleize E, Kurono Y, Iwata S. Cost-Effectiveness Evaluation of the 10-Valent Pneumococcal Non-typeable Haemophilus influenzae Protein D Conjugate Vaccine and 13-Valent Pneumococcal Vaccine in Japanese Children. Infect Dis Ther 2014; 4:93-112. [PMID: 25527448 PMCID: PMC4363214 DOI: 10.1007/s40121-014-0053-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Indexed: 10/29/2022] Open
Abstract
INTRODUCTION Diseases caused by Streptococcus pneumoniae represent a major public health problem. The purpose of this study was to compare, in the Japanese context, the projected health benefits, costs and cost-effectiveness of the latest generation of pneumococcal conjugate vaccines which may provide important insight into the potential public health impact of interventions in the context of local disease-specific epidemiology. METHODS A Markov model was used to compare two vaccination strategies which involve routine infant immunization with either the 13-valent pneumococcal conjugate vaccine (PCV-13; Prevenar 13™, Pfizer, Pearl River, NY, USA) or the 10-valent pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV; Synflorix™, GlaxoSmithKline Biologicals SA, Rixensart, Belgium) over a time horizon of 5 years from the healthcare provider and societal perspectives. Estimates for key model parameters were obtained from locally available databases and published literature. Incremental benefits in terms of costs and quality-adjusted life-year and cost-effectiveness were assessed. RESULTS A 3 + 1 vaccination schedule for infants with PHiD-CV is expected to have a similar impact on invasive pneumococcal disease and pneumonia and a larger impact on acute otitis media-related outcomes compared with PCV-13. Assuming price parity for these vaccines, the model projected that vaccination with PHiD-CV would result in cost savings of 1.9 and 3.9 billion Japanese yen from the provider and societal perspectives, respectively. This was largely due to a reduction in highly prevalent acute otitis media. Vaccination with PHiD-CV was expected to generate a gain of 433 quality-adjusted life-years compared to PCV-13 translating into dominance over PCV-13. Sensitivity analyses showed robustness of model outcome to changes in key model parameters and substantiated that the model outcome was consistently driven by the incremental benefit of PHiD-CV in averting acute otitis media. CONCLUSION In comparison to PCV-13, vaccination with PHiD-CV is projected to be cost saving for Japan from both the healthcare provider and societal perspectives.
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Affiliation(s)
- Makoto Shiragami
- Social and Administrative Pharmacy Science, School of Pharmacy, Nihon University, Funabashi-shi, Chiba Japan
| | - Akiko Mizukami
- Healthoutcomes Department, Development and Medical Affairs Division, GlaxoSmithKline K.K., Shibuya-ku, Tokyo, Japan
| | | | - Tomas Mrkvan
- Vaccine Value and Health Science, GSK Vaccines, Wavre, Belgium
| | | | - Yuichi Kurono
- Department of Otolaryngology, Faculty of Medicine, Kagoshima University, Kagoshima-shi, Kagoshima Japan
| | - Satoshi Iwata
- Department of Infectious Diseases, Keio University School of Medicine, Shinjuku-ku, Tokyo Japan
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Kunthalert D, Novotny LA, Massa HM, Ulett GC, Bakaletz LO, Kyd JM, Cripps AW. Epitope-specific immune recognition of the nontypeable Haemophilus influenzae outer membrane protein 26. Hum Vaccin Immunother 2013; 9:625-35. [PMID: 23292125 PMCID: PMC3891721 DOI: 10.4161/hv.23255] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 10/25/2012] [Indexed: 11/19/2022] Open
Abstract
Previous studies using rodent respiratory infection models of nontypeable Haemophilus influenzae (NTHi) infection have established the 26-kDa outer membrane protein of the bacterium, OMP26, as a potential vaccine antigen for NTHi. This study undertook a comprehensive immunological identification of OMP26 T- and B-cell epitopes. A series of OMP26 peptides were constructed and regions of the OMP26 antigen involved in recognition by lymphocyte receptors and induction of acquired immune responses were identified. The dominant T-cell epitopes for OMP26 were located toward the C-terminus between amino acid residues 95 and 197 (T3+T4 region) as mapped using antigen-specific lymphocyte proliferation assays. The newly identified T-cell epitopes exhibited strong capacity for efficient T-cell activation, suggesting that, compared with other OMP26 regions; epitopes within the T3+T4 region have the highest affinity for binding to major histocompatibility complex molecules. In contrast, the predominant B-cell epitopes of OMP26 were located more centrally within the molecule between amino acid residues 45 and 145 (T2+T3 region) as determined using enzyme-linked immunosorbent assay and surface plasmon resonance assays. The T2+T3 region was immunodominant in several species including chinchilla, mice and rats when assessed using both mucosal and parenteral immunization regimes. In addition, the antibodies directed against the T2+T3 region bound to intact NTHi cell surface, according to flow cytometry. Collectively, these results specifically locate the amino acid sequences containing the OMP26 T- and B-cell epitopes, which, as newly mapped antigenic epitopes for lymphocyte recognition, will be useful to improve existing NTHi vaccine strategies. Comprehensive definition of the minimum epitope length required for optimal B- and T-cell responses requires further study.
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Affiliation(s)
| | - Laura A. Novotny
- The Research Institute at Nationwide Children's Hospital; Columbus, OH USA
| | - Helen M. Massa
- Griffith Health Institute; School of Medical Science; Griffith University; Gold Coast; Southport, QLD Australia
| | - Glen C. Ulett
- Griffith Health Institute; School of Medical Science; Griffith University; Gold Coast; Southport, QLD Australia
| | - Lauren O. Bakaletz
- The Research Institute at Nationwide Children's Hospital; Columbus, OH USA
| | | | - Allan W. Cripps
- Griffith Health Institute; School of Medical Science; Griffith University; Gold Coast; Southport, QLD Australia
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