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Halliday A, Long AE, Baum HE, Thomas AC, Shelley KL, Oliver E, Gupta K, Francis O, Williamson MK, Di Bartolo N, Randell MJ, Ben-Khoud Y, Kelland I, Mortimer G, Ball O, Plumptre C, Chandler K, Obst U, Secchi M, Piemonti L, Lampasona V, Smith J, Gregorova M, Knezevic L, Metz J, Barr R, Morales-Aza B, Oliver J, Collingwood L, Hitchings B, Ring S, Wooldridge L, Rivino L, Timpson N, McKernon J, Muir P, Hamilton F, Arnold D, Woolfson DN, Goenka A, Davidson AD, Toye AM, Berger I, Bailey M, Gillespie KM, Williams AJK, Finn A. Development and evaluation of low-volume tests to detect and characterize antibodies to SARS-CoV-2. Front Immunol 2022; 13:968317. [PMID: 36439154 PMCID: PMC9682908 DOI: 10.3389/fimmu.2022.968317] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 08/30/2022] [Indexed: 11/11/2022] Open
Abstract
Low-volume antibody assays can be used to track SARS-CoV-2 infection rates in settings where active testing for virus is limited and remote sampling is optimal. We developed 12 ELISAs detecting total or antibody isotypes to SARS-CoV-2 nucleocapsid, spike protein or its receptor binding domain (RBD), 3 anti-RBD isotype specific luciferase immunoprecipitation system (LIPS) assays and a novel Spike-RBD bridging LIPS total-antibody assay. We utilized pre-pandemic (n=984) and confirmed/suspected recent COVID-19 sera taken pre-vaccination rollout in 2020 (n=269). Assays measuring total antibody discriminated best between pre-pandemic and COVID-19 sera and were selected for diagnostic evaluation. In the blind evaluation, two of these assays (Spike Pan ELISA and Spike-RBD Bridging LIPS assay) demonstrated >97% specificity and >92% sensitivity for samples from COVID-19 patients taken >21 days post symptom onset or PCR test. These assays offered better sensitivity for the detection of COVID-19 cases than a commercial assay which requires 100-fold larger serum volumes. This study demonstrates that low-volume in-house antibody assays can provide good diagnostic performance, and highlights the importance of using well-characterized samples and controls for all stages of assay development and evaluation. These cost-effective assays may be particularly useful for seroprevalence studies in low and middle-income countries.
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Affiliation(s)
- Alice Halliday
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Anna E. Long
- Diabetes and Metabolism, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Holly E. Baum
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
- School of Chemistry, University of Bristol, Bristol, United Kingdom
| | - Amy C. Thomas
- Bristol Veterinary School, University of Bristol, Bristol, United Kingdom
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Kathryn L. Shelley
- School of Chemistry, University of Bristol, Bristol, United Kingdom
- School of Biochemistry, Biomedical Sciences Building, University Walk, University of Bristol, Bristol, United Kingdom
| | - Elizabeth Oliver
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Kapil Gupta
- School of Biochemistry, Biomedical Sciences Building, University Walk, University of Bristol, Bristol, United Kingdom
| | - Ore Francis
- Bristol Veterinary School, University of Bristol, Bristol, United Kingdom
| | | | - Natalie Di Bartolo
- School of Biochemistry, Biomedical Sciences Building, University Walk, University of Bristol, Bristol, United Kingdom
| | - Matthew J. Randell
- Diabetes and Metabolism, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Yassin Ben-Khoud
- Diabetes and Metabolism, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Ilana Kelland
- Diabetes and Metabolism, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Georgina Mortimer
- Diabetes and Metabolism, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Olivia Ball
- Diabetes and Metabolism, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Charlie Plumptre
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Kyla Chandler
- Diabetes and Metabolism, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Ulrike Obst
- School of Chemistry, University of Bristol, Bristol, United Kingdom
| | - Massimiliano Secchi
- Diabetes Research Institute, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Lorenzo Piemonti
- Diabetes Research Institute, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Vito Lampasona
- Diabetes Research Institute, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Joyce Smith
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Michaela Gregorova
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Lea Knezevic
- Bristol Veterinary School, University of Bristol, Bristol, United Kingdom
| | - Jane Metz
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
- Department of Paediatric Immunology and Infectious Diseases, Bristol Royal Hospital for Children, Bristol, United Kingdom
| | - Rachael Barr
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
- Department of Paediatric Immunology and Infectious Diseases, Bristol Royal Hospital for Children, Bristol, United Kingdom
| | - Begonia Morales-Aza
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Jennifer Oliver
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Lucy Collingwood
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Benjamin Hitchings
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Susan Ring
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- MRC Integrative Epidemiology Unit at University of Bristol, Bristol, United Kingdom
| | - Linda Wooldridge
- Bristol Veterinary School, University of Bristol, Bristol, United Kingdom
| | - Laura Rivino
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Nicholas Timpson
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- MRC Integrative Epidemiology Unit at University of Bristol, Bristol, United Kingdom
| | - Jorgen McKernon
- National Infection Service, UK Health Security Agency, Southmead Hospital, Bristol, United Kingdom
| | - Peter Muir
- National Infection Service, UK Health Security Agency, Southmead Hospital, Bristol, United Kingdom
| | - Fergus Hamilton
- MRC Integrative Epidemiology Unit at University of Bristol, Bristol, United Kingdom
- Academic Respiratory Unit, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - David Arnold
- Academic Respiratory Unit, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Derek N. Woolfson
- School of Chemistry, University of Bristol, Bristol, United Kingdom
- School of Biochemistry, Biomedical Sciences Building, University Walk, University of Bristol, Bristol, United Kingdom
- Bristol BioDesign Institute, University of Bristol, Bristol, United Kingdom
| | - Anu Goenka
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
- Department of Paediatric Immunology and Infectious Diseases, Bristol Royal Hospital for Children, Bristol, United Kingdom
| | - Andrew D. Davidson
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Ashley M. Toye
- School of Biochemistry, Biomedical Sciences Building, University Walk, University of Bristol, Bristol, United Kingdom
- Bristol BioDesign Institute, University of Bristol, Bristol, United Kingdom
- Bristol Institute of Transfusion Sciences, NHS Blood and Transplant Filton, Bristol, United Kingdom
| | - Imre Berger
- School of Chemistry, University of Bristol, Bristol, United Kingdom
- School of Biochemistry, Biomedical Sciences Building, University Walk, University of Bristol, Bristol, United Kingdom
- Bristol BioDesign Institute, University of Bristol, Bristol, United Kingdom
| | - Mick Bailey
- Bristol Veterinary School, University of Bristol, Bristol, United Kingdom
| | - Kathleen M. Gillespie
- Diabetes and Metabolism, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Alistair J. K. Williams
- Diabetes and Metabolism, Bristol Medical School, University of Bristol, Bristol, United Kingdom
| | - Adam Finn
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
- Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, United Kingdom
- Department of Paediatric Immunology and Infectious Diseases, Bristol Royal Hospital for Children, Bristol, United Kingdom
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Carr JP, MacLennan JM, Plested E, Bratcher HB, Harrison OB, Aley PK, Bray JE, Camara S, Rodrigues CMC, Davis K, Bartolf A, Baxter D, Cameron JC, Cunningham R, Faust SN, Fidler K, Gowda R, Heath PT, Hughes S, Khajuria S, Orr D, Raman M, Smith A, Turner DP, Whittaker E, Williams CJ, Zipitis CS, Pollard AJ, Oliver J, Morales-Aza B, Lekshmi A, Clark SA, Borrow R, Christensen H, Trotter C, Finn A, Maiden MCJ, Snape MD. Impact of meningococcal ACWY conjugate vaccines on pharyngeal carriage in adolescents: evidence for herd protection from the UK MenACWY programme. Clin Microbiol Infect 2022; 28:1649.e1-1649.e8. [PMID: 35840033 DOI: 10.1016/j.cmi.2022.07.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 07/04/2022] [Accepted: 07/06/2022] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Serogroup W and Y invasive meningococcal disease (IMD) increased globally from 2000 onwards. Responding to a rapid increase in serogroup W clonal complex 11 (W:cc11) IMD, the UK replaced an adolescent booster dose of meningococcal C conjugate vaccine with quadrivalent MenACWY conjugate vaccine in 2015. By 2018, vaccine coverage in the eligible school cohorts aged 14-19 years-old was 84%. We assessed the impact of the MenACWY vaccination programme on meningococcal carriage. METHODS An observational study of culture-defined oropharyngeal meningococcal carriage prevalence before and after the start of the MenACWY vaccination programme in UK school students, aged 15-19 years, using two cross-sectional studies: 2014-15 "UKMenCar4" and 2018 "Be on the TEAM" (ISRCTN75858406). RESULTS A total of 10625 participants pre-implementation and 13434 post-implementation were included. Carriage of genogroups C, W, and Y (combined) decreased from 2·03% to 0·71% (OR 0·34 [95% CI 0·27-0·44] p<0·001). Carriage of genogroup B meningococci did not change (1·26% vs 1·23% [95% CI 0.77-1.22] p=0·80) and genogroup C remained rare (n = 7/10625 vs 17/13488, p=0·135). The proportion of serogroup positive isolates, i.e., those expressing capsule, decreased for genogroup W by 53.8% (95% CI -5.0%-79.8%, p=0·016) and for genogroup Y by 30·1% (95% CI 8·9%-46·3%, p=0·0025). CONCLUSIONS The UK MenACWY vaccination programme reduced carriage acquisition of genogroup and serogroup Y and W meningococci and sustained low levels of genogroup C carriage. These data support the use of quadrivalent MenACWY conjugate vaccine for indirect (herd) protection.
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Affiliation(s)
- Jeremy P Carr
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford, UK; Monash University, Melbourne, Australia; Monash Children's Hospital, Melbourne, Australia
| | | | - Emma Plested
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford, UK
| | | | | | - Parvinder K Aley
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford, UK
| | | | - Susana Camara
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford, UK
| | - Charlene M C Rodrigues
- Department of Zoology, University of Oxford, UK; Department of Paediatric Infectious Diseases, Great Ormond Street Hospital for Children NHS Foundation Trust, UK
| | - Kimberly Davis
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford, UK
| | - Angela Bartolf
- St George's Vaccine Institute, Institute of Infection & Immunity; St George's University of London, UK
| | | | | | | | - Saul N Faust
- NIHR Southampton Clinical Research Facility and NIHR Southampton Biomedical Research Centre, University Hospital Southampton NHS Foundation Trust; and Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK
| | - Katy Fidler
- Brighton and Sussex Medical School, UK; Royal Alexandra Children's Hospital, University Hospital Sussex NHS Foundation Trust, Brighton, UK
| | | | - Paul T Heath
- St George's Vaccine Institute, Institute of Infection & Immunity; St George's University of London, UK
| | - Stephen Hughes
- Royal Manchester Children's Hospital; Manchester University NHS Foundation Trust, UK
| | | | - David Orr
- Lancashire Teaching Hospitals NHS Foundation Trust, UK
| | - Mala Raman
- University Hospitals Plymouth NHS Foundation Trust, UK
| | - Andrew Smith
- Glasgow Dental Hospital & School, College of Medical, Veterinary & Life Sciences, University of Glasgow, UK
| | - David Pj Turner
- School of Life Sciences, University of Nottingham & Nottingham University Hospitals NHS Trust, UK
| | - Elizabeth Whittaker
- Imperial College London, UK; Imperial College Healthcare NHS Trust, London, UK
| | | | - Christos S Zipitis
- Wrightington, Wigan and Leigh Teaching Hospitals NHS Foundation Trust, UK
| | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford, UK
| | - Jennifer Oliver
- Bristol Children's Vaccine Centre, University of Bristol, UK
| | | | - Aiswarya Lekshmi
- UK Health Security Agency Meningococcal Reference Unit, Manchester Royal Infirmary Manchester, UK
| | - Stephen A Clark
- UK Health Security Agency Meningococcal Reference Unit, Manchester Royal Infirmary Manchester, UK
| | - Ray Borrow
- UK Health Security Agency Meningococcal Reference Unit, Manchester Royal Infirmary Manchester, UK
| | - Hannah Christensen
- School of Population Health Sciences, Bristol Medical School, University of Bristol, UK
| | | | - Adam Finn
- School of Population Health Sciences, Bristol Medical School, University of Bristol, UK
| | - Martin C J Maiden
- Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford, OX1 3SZ, United Kingdom.
| | - Matthew D Snape
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, and the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre, Oxford, UK
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Thomas AC, Bailey M, Lee MRF, Mead A, Morales-Aza B, Reynolds R, Vipond B, Finn A, Eisler MC. Insights into Pasteurellaceae carriage dynamics in the nasal passages of healthy beef calves. Sci Rep 2019; 9:11943. [PMID: 31420565 PMCID: PMC6697682 DOI: 10.1038/s41598-019-48007-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 07/16/2019] [Indexed: 12/22/2022] Open
Abstract
We investigated three bovine respiratory pathobionts in healthy cattle using qPCR optimised and validated to quantify Histophilus somni, Mannheimia haemolytica and Pasteurella multocida over a wide dynamic range. A longitudinal study was conducted to investigate the carriage and density of these bacteria in the nasal passages of healthy beef calves (N = 60) housed over winter in an experimental farm setting. The three pathobiont species exhibited remarkably different carriage rates and density profiles. At housing, high carriage rates were observed for P. multocida (95%), and H. somni (75%), while fewer calves were positive for M. haemolytica (13%). Carriage rates for all three bacterial species declined over the 75-day study, but not all individuals became colonised despite sharing of environment and airspace. Colonisation patterns ranged from continuous to intermittent and were different among pathobiont species. Interval-censored exponential survival models estimated the median duration of H. somni and P. multocida carriage at 14.8 (CI95%: 10.6–20.9) and 55.5 (CI95%: 43.3–71.3) days respectively, and found higher density P. multocida carriage was associated with slower clearance (p = 0.036). This work offers insights into the dynamics of pathobiont carriage and provides a potential platform for further data collection and modelling studies.
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Affiliation(s)
- A C Thomas
- Bristol Veterinary School, University of Bristol, Langford, UK. .,Rothamsted Research, North Wyke, Devon, UK. .,Bristol Children's Vaccine Centre, University of Bristol, Bristol, UK.
| | - M Bailey
- Bristol Veterinary School, University of Bristol, Langford, UK
| | - M R F Lee
- Bristol Veterinary School, University of Bristol, Langford, UK.,Rothamsted Research, North Wyke, Devon, UK
| | - A Mead
- Rothamsted Research, Harpenden, UK
| | - B Morales-Aza
- Bristol Children's Vaccine Centre, University of Bristol, Bristol, UK.,School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - R Reynolds
- School of Population Health Sciences, University of Bristol, Bristol, UK
| | - B Vipond
- Public Health Laboratory Bristol, Public Health England, Bristol, UK
| | - A Finn
- Bristol Children's Vaccine Centre, University of Bristol, Bristol, UK.,School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK.,School of Population Health Sciences, University of Bristol, Bristol, UK
| | - M C Eisler
- Bristol Veterinary School, University of Bristol, Langford, UK.
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4
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Thors V, Christensen H, Morales-Aza B, Oliver E, Sikora P, Vipond I, Muir P, Finn A. High-density Bacterial Nasal Carriage in Children Is Transient and Associated With Respiratory Viral Infections-Implications for Transmission Dynamics. Pediatr Infect Dis J 2019; 38:533-538. [PMID: 30985547 DOI: 10.1097/inf.0000000000002256] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND This longitudinal study describes the associations between respiratory viral infections, rhinitis and the prevalence and density of the common nasopharyngeal bacterial colonizers, Streptococcus pneumoniae (Sp), Moraxella catarrhalis (Mc), Haemophilus influenzae (Hi) and Staphylococcus aureus. METHODS In an observational cohort study, 161 children attending day care centers in Bristol, United Kingdom, were recruited. Monthly nasopharyngeal swabs were taken and stored frozen in Skim-milk, tryptone, glucose and glycerin broth (STGG) broth. Quantitative polymerase chain reaction was used for detection of respiratory viruses and 4 bacterial species. t tests and logistic regression models were used for analysis. RESULTS The frequent colonisers, Sp, Mc and Hi were more frequently found at high density in contrast to Staphylococcus aureus although temporally, high-density carriage was short lived. Respiratory viral infections and symptoms of rhinitis were both independently and consistently associated with higher bacterial density with an observed 2-fold increase in density for Sp, Mc and Hi (P = 0.004-0.017). CONCLUSIONS For Sp and Hi, the association between young age and higher bacterial DNA density was explained by more frequent viral infection and increased nasal discharge, while the associations between some viral specie's and some bacterial species' density appear to be stronger than others. Increased colonization density and rhinitis may promote transmission of these commonly carried organisms.
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Affiliation(s)
- Valtyr Thors
- From the School of Cellular and Molecular Medicine, University of Bristol, Education Centre, Bristol, United Kingdom
- Children's Hospital, Landspitali University Hospital Iceland, Reykjavik, Iceland
| | | | - Begonia Morales-Aza
- From the School of Cellular and Molecular Medicine, University of Bristol, Education Centre, Bristol, United Kingdom
| | - Elizabeth Oliver
- From the School of Cellular and Molecular Medicine, University of Bristol, Education Centre, Bristol, United Kingdom
| | - Paulina Sikora
- From the School of Cellular and Molecular Medicine, University of Bristol, Education Centre, Bristol, United Kingdom
| | - Ian Vipond
- Public Health Laboratory Bristol, Public Health England, Southmead Hospital, Bristol, United Kingdom
| | - Peter Muir
- Public Health Laboratory Bristol, Public Health England, Southmead Hospital, Bristol, United Kingdom
| | - Adam Finn
- From the School of Cellular and Molecular Medicine, University of Bristol, Education Centre, Bristol, United Kingdom
- School of Population Health Sciences, University of Bristol
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5
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Rodrigues F, Christensen H, Morales-Aza B, Sikora P, Oliver E, Oliver J, Lucidarme J, Marlow R, Januário L, Finn A. Viable Neisseria meningitidis is commonly present in saliva in healthy young adults: Non-invasive sampling and enhanced sensitivity of detection in a follow-up carriage study in Portuguese students. PLoS One 2019; 14:e0209905. [PMID: 30742640 PMCID: PMC6370198 DOI: 10.1371/journal.pone.0209905] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Accepted: 12/13/2018] [Indexed: 12/04/2022] Open
Abstract
Introduction and aims Improved sensitivity and efficiency of detection and quantification of carriage of Neisseria meningitidis (Nm) in young people is important for evaluation of the impact of vaccines upon transmission and associated population-wide effects. Saliva collection is quick, non-invasive and facilitates frequent sampling, but has been reported to yield low sensitivity by culture. We re-evaluated this approach in a follow-up cross sectional study using direct and culture-amplified PCR. Material/Methods In April 2016 we collected paired oropharyngeal swabs (OPS) and saliva samples from 1005 healthy students in Portugal into STGG broth and stored them at -80°C until DNA extraction and batched qPCR analysis. Samples were also cultured on GC agar plates for 72h and PCR done on DNA extracts from overall growth. Nm isolates were also sought from a selection of 50 samples. qPCR amplification targets were superoxide dismutase sodC and capsular locus/genogroup-specific genes (B, C, W, X and Y) and, for cultured isolates only, porA. Cycle threshold values of ≤36 were considered positive. Results 556 tests (460 samples, 363 subjects, 36.1%) were positive for Nm (sodC) and 65 (45, 36, 3.6%) for MenB. More salivas were positive by direct sodC qPCR (211, 21.0%) than OPS (126, 12.5%) but fewer were positive by culture-amplified qPCR (94 vs. 125). For both sample types, many that were negative on direct qPCR came positive on culture-amplification and Nm was consistently isolated from salivas in which culture amplified the PCR signal. Using both methods on both samples yielded 36.1% Nm and 5.5% encapsulated Nm carriage rates while direct qPCR on OPS alone detected 12.5% and 2.2%. Conclusions Detectable MenB carriage rates (2.9%) were lower than 4 years earlier (6.8%) in this population (p = 0.0003). Viable meningococci were often present in saliva. Although evidence of encapsulated Nm was less frequent in saliva than OPS, collection is more acceptable to subjects allowing more frequent sampling. Use of culture-amplification increases detection sensitivity in both sample types, especially when combined with direct PCR. Combining these samples and/or methodologies could greatly enhance the power of carriage studies to detect the impact of vaccines upon carriage and transmission.
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Affiliation(s)
- Fernanda Rodrigues
- Hospital Pediátrico, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
- Faculdade de Medicina, Universidade de Coimbra, Coimbra, Portugal
- * E-mail:
| | - Hannah Christensen
- School of Population Health Sciences, University of Bristol, Bristol, United Kingdom
| | - Begonia Morales-Aza
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Paulina Sikora
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Elizabeth Oliver
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Jennifer Oliver
- School of Population Health Sciences, University of Bristol, Bristol, United Kingdom
| | - Jay Lucidarme
- Meningococcal Reference Unit, Public Health England, Manchester, United Kingdom
| | - Robin Marlow
- School of Population Health Sciences, University of Bristol, Bristol, United Kingdom
| | - Luís Januário
- Hospital Pediátrico, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - Adam Finn
- School of Population Health Sciences, University of Bristol, Bristol, United Kingdom
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
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6
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Thors V, Christensen H, Morales-Aza B, Vipond I, Muir P, Finn A. The Effects of Live Attenuated Influenza Vaccine on Nasopharyngeal Bacteria in Healthy 2 to 4 Year Olds. A Randomized Controlled Trial. Am J Respir Crit Care Med 2017; 193:1401-9. [PMID: 26742001 DOI: 10.1164/rccm.201510-2000oc] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
RATIONALE Viral infections of the upper respiratory tract may influence the commensal nasopharyngeal bacteria. Changes in the bacterial niche could affect transmission dynamics. Attenuated vaccine viruses can be used to investigate this empirically in humans. OBJECTIVES To study the effects of mild viral upper respiratory infections on nasopharyngeal bacterial colonization using live attenuated influenza vaccine (LAIV) as a surrogate. METHODS We used trivalent LAIV to evaluate the effects of viral infection on bacterial carriage and density of Streptococcus pneumoniae, Moraxella catarrhalis, Haemophilus influenzae, and Staphylococcus aureus. A total of 151 healthy children were randomized 1:1 to receive the vaccine starting either at recruitment (n = 74) or 28 days later (n = 77) in a stepped wedge fashion, allowing comparisons between recipients and nonrecipients as well as whole-group comparisons pre- and postvaccination. Bacterial carriage and density were determined using quantitative polymerase chain reaction assays. MEASUREMENTS AND MAIN RESULTS A total of 151 children were recruited, 77 in the LAIV group and 74 in the control group. LAIV recipients (n = 63 analyzed) showed an apparent transient increase in H. influenzae carriage but no further significant differences in carriage prevalence of the four bacterial species compared with controls (n = 72 analyzed). S. pneumoniae density was substantially higher in vaccine recipients (16,687 vs. 1935 gene copies per milliliter) 28 days after the first dose (P < 0.001). Whole-group multivariable analysis (prevaccine, after one dose, and after two doses) also showed increases in density of other species and H. influenzae carriage prevalence. CONCLUSIONS In the absence of any safety signals despite widespread use of the vaccine, these findings suggest that bacterial density, and thus transmission rates among children and to people in other age groups, may rise following attenuated influenza infections without associated clinical disease. LAIV could therefore be used as an experimental tool to elucidate the dynamics of transmission of nasopharyngeal bacteria.
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Affiliation(s)
| | - Hannah Christensen
- 2 School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom; and
| | | | - Ian Vipond
- 3 Public Health Laboratory Bristol, Public Health England, Bristol, United Kingdom
| | - Peter Muir
- 3 Public Health Laboratory Bristol, Public Health England, Bristol, United Kingdom
| | - Adam Finn
- 1 School of Cellular and Molecular Medicine and
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7
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Trück J, Thompson A, Morales-Aza B, Clutterbuck EA, Voysey M, Clarke E, Snape MD, Kelly DF, Finn A, Pollard AJ. Memory B cell response to a PCV-13 booster in 3.5year old children primed with either PCV-7 or PCV-13. Vaccine 2017; 35:2701-2708. [PMID: 28392142 DOI: 10.1016/j.vaccine.2017.03.079] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/28/2017] [Accepted: 03/29/2017] [Indexed: 01/25/2023]
Abstract
Pneumococcal protein-polysaccharide conjugate vaccines provide direct protection against Streptococcus pneumoniae through the induction of persistent anti-polysaccharide antibodies, and by priming for a rapid secondary antibody response. Memory B cells (BMEM) generated during an initial immune response are responsible for both the more rapid and quantitatively greater secondary antibody response and are also thought to contribute to the ongoing production of plasma cells providing long-term antibody persistence. We recruited 3.5-year-old children who had participated in a previous clinical trial comparing infant immunization with either a 7-valent (PCV-7) or a 13-valent pneumococcal conjugate vaccine (PCV-13) to investigate whether prior priming with pneumococcal antigens influences BMEM responses. Blood was taken before and 1month after a PCV-13 booster. BMEM were quantified using a cultured ELISpot assay for pneumococcal serotypes 1, 3, 4, 14, 19A, 23F, and with diphtheria and tetanus toxoid as controls, and then correlated with serotype-specific IgG concentrations and opsonophagocytic activity (OPA) titers. In total, blood samples from 62 participants were available for analysis. Serotype-specific BMEM frequencies were generally low at baseline (before boost) although for serotypes 14 and 3, they were significantly higher in children primed with PCV-13 than PCV-7 primed children. Following the PCV-13 booster, BMEM frequencies increased and were not different between the groups for all serotypes. A strong inverse correlation was found between antibody concentrations and OPA titers at baseline and BMEM following booster vaccination for serotype 3 but not for other serotypes suggesting that, for this serotype, pre-existing serotype-specific antibodies may inhibit BMEM formation in response to vaccination. Clinicaltrials.gov registration number: NCT01095471.
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Affiliation(s)
- Johannes Trück
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK.
| | - Amber Thompson
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Begonia Morales-Aza
- Bristol Children's Vaccine Centre, University Hospitals Bristol NHS Foundation Trust and University of Bristol, Bristol, UK
| | - Elizabeth A Clutterbuck
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Merryn Voysey
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Ed Clarke
- Bristol Children's Vaccine Centre, University Hospitals Bristol NHS Foundation Trust and University of Bristol, Bristol, UK; Vaccines and Immunity Theme, MRC Unit, The Gambia, Gambia
| | - Matthew D Snape
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Dominic F Kelly
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK
| | - Adam Finn
- Bristol Children's Vaccine Centre, University Hospitals Bristol NHS Foundation Trust and University of Bristol, Bristol, UK
| | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, Oxford, UK
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8
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Thors V, Morales-Aza B, Pidwill G, Vipond I, Muir P, Finn A. Population density profiles of nasopharyngeal carriage of 5 bacterial species in pre-school children measured using quantitative PCR offer potential insights into the dynamics of transmission. Hum Vaccin Immunother 2016; 12:375-82. [PMID: 26367344 DOI: 10.1080/21645515.2015.1090069] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Bacterial vaccines can reduce carriage rates. Colonization is usually a binary endpoint. Real time quantitative PCR (qPCR) can quantify bacterial DNA in mucosal samples over a wide range. Using culture and single-gene species-specific qPCRs for Streptococcus pneumoniae (lytA), Streptococcus pyogenes (ntpC), Moraxella catarrhalis (ompJ), Haemophilus influenzae (hdp) and Staphylococcus aureus (nuc) and standard curves against log-phase reference strain broth cultures we described frequency and peak density distributions of carriage in nasopharyngeal swabs from 161 healthy 2-4 y old children collected into STGG broth. In general, detection by qPCR and culture was consistent. Discordance mostly occurred at lower detection thresholds of both methods, although PCR assays for S. pyogenes and S. aureus were less sensitive. Density varied across 5-7 orders of magnitude for the 5 species with the abundant species skewed toward high values (modes: S. pneumoniae log3-4, M. catarrhalis & H. influenzae log4-5 CFU/ml broth). Wide ranges of bacterial DNA concentrations in healthy children carrying these bacteria could mean that different individuals at different times vary greatly in infectiousness. Understanding the host, microbial and environmental determinants of colonization density will permit more accurate prediction of vaccine effectiveness.
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Affiliation(s)
- Valtyr Thors
- a University of Bristol; School of Cellular and Molecular Medicine ; Bristol , UK
| | - Begonia Morales-Aza
- a University of Bristol; School of Cellular and Molecular Medicine ; Bristol , UK
| | - Grace Pidwill
- a University of Bristol; School of Cellular and Molecular Medicine ; Bristol , UK
| | - Ian Vipond
- b Public Health Laboratory Bristol; Public Health England ; Bristol , UK
| | - Peter Muir
- b Public Health Laboratory Bristol; Public Health England ; Bristol , UK
| | - Adam Finn
- a University of Bristol; School of Cellular and Molecular Medicine ; Bristol , UK
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9
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Rodrigues F, Danon L, Morales-Aza B, Sikora P, Thors V, Ferreira M, Gould K, Hinds J, Finn A. Pneumococcal Serotypes Colonise the Nasopharynx in Children at Different Densities. PLoS One 2016; 11:e0163435. [PMID: 27685088 PMCID: PMC5042462 DOI: 10.1371/journal.pone.0163435] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 09/08/2016] [Indexed: 01/18/2023] Open
Abstract
Prevalence of pneumococcal serotypes in carriage and disease has been described but absolute serotype colonisation densities have not been reported. 515 paediatric nasal swab DNA extracts were subjected to lytA qPCR and molecular serotyping by microarray. Absolute serotype densities were derived from total pneumococcal density (qPCR cycle threshold and standard curve) and relative abundance (microarray) and varied widely. Compared to all serotype densities observed, the strongest evidence of differences was seen for serotypes 21 and 35B (higher) and 3, 38 and non-typeables (lower) (p<0.05) with a similar hierarchy when only a single serotype carriage was assessed. There was no evidence of any overall density differences between children with single or multiple serotypes detected but serotypes with mid-range densities were more prevalent. The hierarchy of distinct pneumococcal serotype carriage densities described here for the first time, may help explain the dynamics of transmission between children.
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Affiliation(s)
- Fernanda Rodrigues
- Hospital Pediátrico Coimbra, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
- Faculty of Medicine, Universidade de Coimbra, Coimbra, Portugal
- * E-mail:
| | - Leon Danon
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom
| | - Begonia Morales-Aza
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Paulina Sikora
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Valtyr Thors
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Muriel Ferreira
- Hospital Pediátrico Coimbra, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - Katherine Gould
- Institute for Infection and Immunity, St. George's, University of London, London, United Kingdom
- BUGS Bioscience, London Bioscience Innovation Centre, London, United Kingdom
| | - Jason Hinds
- Institute for Infection and Immunity, St. George's, University of London, London, United Kingdom
- BUGS Bioscience, London Bioscience Innovation Centre, London, United Kingdom
| | - Adam Finn
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
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Trück J, Mitchell R, Thompson AJ, Morales-Aza B, Clutterbuck EA, Kelly DF, Finn A, Pollard AJ. Effect of cryopreservation of peripheral blood mononuclear cells (PBMCs) on the variability of an antigen-specific memory B cell ELISpot. Hum Vaccin Immunother 2015; 10:2490-6. [PMID: 25424961 DOI: 10.4161/hv.29318] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The ELISpot assay is used in vaccine studies for the quantification of antigen-specific memory B cells (B(MEM)), and can be performed using cryopreserved samples. The effects of cryopreservation on B(MEM) detection and the consistency of cultured ELISpot assays when performed by different operators or laboratories are unknown. In this study, blood was taken from healthy volunteers, and a cultured ELISpot assay was used to count B(MEM) specific for 2 routine vaccine antigens (diphtheria and tetanus toxoid). Results were assessed for intra- and inter-operator variation, and the effects of cryopreservation. Cryopreserved samples were shipped to a second laboratory in order to assess inter-laboratory variation. B(MEM) frequencies were very strongly correlated when comparing fresh and frozen samples processed by the same operator, and were also very strongly correlated when comparing 2 operators in the same laboratory. Results were slightly less consistent when samples were processed in different laboratories but correlation between the 2 measurements was still very strong. Although cell viability was reduced in some cryopreserved samples due to higher temperatures during transportation, B(MEM) could still be quantified. These results demonstrate the reproducibility of the ELISpot assay across operators and laboratories, and support the use of cryopreserved samples in future B(MEM) studies.
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Affiliation(s)
- Johannes Trück
- a Oxford Vaccine Group; Department of Paediatrics; University of Oxford and the NIHR Oxford Biomedical Research Centre; Oxford, UK
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11
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Read RC, Baxter D, Chadwick DR, Faust SN, Finn A, Gordon SB, Heath PT, Lewis DJM, Pollard AJ, Turner DPJ, Bazaz R, Ganguli A, Havelock T, Neal KR, Okike IO, Morales-Aza B, Patel K, Snape MD, Williams J, Gilchrist S, Gray SJ, Maiden MCJ, Toneatto D, Wang H, McCarthy M, Dull PM, Borrow R. Effect of a quadrivalent meningococcal ACWY glycoconjugate or a serogroup B meningococcal vaccine on meningococcal carriage: an observer-blind, phase 3 randomised clinical trial. Lancet 2014; 384:2123-31. [PMID: 25145775 DOI: 10.1016/s0140-6736(14)60842-4] [Citation(s) in RCA: 216] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
BACKGROUND Meningococcal conjugate vaccines protect individuals directly, but can also confer herd protection by interrupting carriage transmission. We assessed the effects of meningococcal quadrivalent glycoconjugate (MenACWY-CRM) or serogroup B (4CMenB) vaccination on meningococcal carriage rates in 18-24-year-olds. METHODS In this phase 3, observer-blind, randomised controlled trial, university students aged 18-24 years from ten sites in England were randomly assigned (1:1:1, block size of three) to receive two doses 1 month apart of Japanese Encephalitis vaccine (controls), 4CMenB, or one dose of MenACWY-CRM then placebo. Participants were randomised with a validated computer-generated random allocation list. Participants and outcome-assessors were masked to the treatment group. Meningococci were isolated from oropharyngeal swabs collected before vaccination and at five scheduled intervals over 1 year. Primary outcomes were cross-sectional carriage 1 month after each vaccine course. Secondary outcomes included comparisons of carriage at any timepoint after primary analysis until study termination. Reactogenicity and adverse events were monitored throughout the study. Analysis was done on the modified intention-to-treat population, which included all enrolled participants who received a study vaccination and provided at least one assessable swab after baseline. This trial is registered with ClinicalTrials.gov, registration number NCT01214850. FINDINGS Between Sept 21 and Dec 21, 2010, 2954 participants were randomly assigned (987 assigned to control [984 analysed], 979 assigned to 4CMenB [974 analysed], 988 assigned to MenACWY-CRM [983 analysed]); 33% of the 4CMenB group, 34% of the MenACWY-CRM group, and 31% of the control group were positive for meningococcal carriage at study entry. By 1 month, there was no significant difference in carriage between controls and 4CMenB (odds ratio 1·2, 95% CI 0·8-1·7) or MenACWY-CRM (0·9, [0·6-1·3]) groups. From 3 months after dose two, 4CMenB vaccination resulted in significantly lower carriage of any meningococcal strain (18·2% [95% CI 3·4-30·8] carriage reduction), capsular groups BCWY (26·6% [10·5-39·9] carriage reduction), capsular groups CWY (29·6% [8·1-46·0] carriage reduction), and serogroups CWY (28·5% [2·8-47·5] carriage reduction) compared with control vaccination. Significantly lower carriage rates were also noted in the MenACWY-CRM group compared with controls: 39·0% (95% CI 17·3-55·0) carriage reduction for serogroup Y and 36·2% (15·6-51·7) carriage reduction for serogroup CWY. Study vaccines were generally well tolerated, with increased rates of transient local injection pain and myalgia in the 4CMenB group. No safety concerns were identified. INTERPRETATION Although we detected no significant difference between groups at 1 month after vaccine course, MenACWY-CRM and 4CMenB vaccines reduced meningococcal carriage rates during 12 months after vaccination and therefore might affect transmission when widely implemented. FUNDING Novartis Vaccines.
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Affiliation(s)
- Robert C Read
- Academic Unit of Clinical Experimental Sciences and NIHR Southampton Respiratory Biomedical Research Unit, Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK.
| | - David Baxter
- Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK
| | | | - Saul N Faust
- Academic Unit of Clinical Experimental Sciences and NIHR Southampton Respiratory Biomedical Research Unit, Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK; Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Adam Finn
- Schools of Clinical Science and Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Stephen B Gordon
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Paul T Heath
- Division of Clinical Sciences, St George's, University of London, London, UK
| | - David J M Lewis
- Surrey Clinical Research Centre, University of Surrey, Guildford, UK
| | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Centre, Oxford, UK
| | - David P J Turner
- Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Rohit Bazaz
- Department of Infection and Immunity, University of Sheffield, Sheffield, UK
| | - Amitava Ganguli
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Tom Havelock
- Academic Unit of Clinical Experimental Sciences and NIHR Southampton Respiratory Biomedical Research Unit, Faculty of Medicine and Institute for Life Sciences, University of Southampton, Southampton, UK; Southampton NIHR Wellcome Trust Clinical Research Facility, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Keith R Neal
- Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | | | - Begonia Morales-Aza
- Schools of Clinical Science and Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Kamlesh Patel
- NIHR Wellcome Trust Clinical Research Facility, Manchester Royal Infirmary, Manchester, UK
| | - Matthew D Snape
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Centre, Oxford, UK
| | - John Williams
- The James Cook University Hospital, Middlesborough, UK
| | | | - Steve J Gray
- Public Health England, Manchester Royal Infirmary, Manchester, UK
| | | | | | - Huajun Wang
- Novartis Vaccines and Diagnostics, Cambridge, MA, USA
| | | | - Peter M Dull
- Novartis Vaccines and Diagnostics, Cambridge, MA, USA
| | - Ray Borrow
- Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK; Public Health England, Manchester Royal Infirmary, Manchester, UK
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Thors V, Morales-Aza B, Oliver E, Vipond B, Muir P, Finn A. 1060The Effect of Live Attenuated Influenza Vaccine (LAIV) on Bacterial Colonization in Healthy 2-4 Year Old Children. A Randomised Controlled Study. Open Forum Infect Dis 2014. [PMCID: PMC5782190 DOI: 10.1093/ofid/ofu052.768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Valtyr Thors
- Pediatric Infectious Diseases and Immunology, University of Bristol, Bristol, United Kingdom
| | | | - Elizabeth Oliver
- Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Barry Vipond
- Public Health England, Bristol Laboratories, Bristol, United Kingdom
| | - Peter Muir
- Public Health England, Bristol Laboratories, Bristol, United Kingdom
| | - Adam Finn
- School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
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Rodrigues F, Morales-Aza B, Holland R, Gould K, Hinds J, Gonçalves G, Januário L, Finn A. Resurgence of Serotype 19F Carriage in Preschool Children in Portugal in the Context of Continuing Moderate Conjugate Pneumococcal Vaccine Uptake. Clin Infect Dis 2013; 57:473-4. [DOI: 10.1093/cid/cit233] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Dumitrescu AL, Abd-El-Aleem S, Morales-Aza B, Donaldson LF. A model of periodontitis in the rat: effect of lipopolysaccharide on bone resorption, osteoclast activity, and local peptidergic innervation. J Clin Periodontol 2004; 31:596-603. [PMID: 15257734 DOI: 10.1111/j.1600-051x.2004.00528.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To establish and characterise a rat model of periodontitis that reiterates the features of human disease. METHODS Periodontal inflammation was induced by a single injection of 10 microg liposaccharide (LPS) (Salmonella typhimurium) in 1 microl saline into rat mandibular gingiva at the buccomesial aspect of the second molar. Animals were killed after 3, 7 and 10 days, mandibles dissected and sectioned for histological and immunocytochemical analysis. RESULTS LPS injection resulted in a significant gingival and periodontal inflammation with inflammatory infiltrate, apical migration of the junctional epithelium, interdental bone loss, and activation of osteoclasts at the site of injection 7 and 10 days after injection. At 10 days post injection, there was a significant trend for bone loss on both sides of the mandible. Periodontal inflammation was associated with alteration in the levels of calcitonin gene-related peptide-like immunoreactivity in nerve terminals innervating the inflamed gingival papilla. CONCLUSION Intragingival injection of LPS in the rat provides an easily induced reproducible experimental model of periodontal inflammation that reiterates features of human disease.
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