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  1. Article ; Online: Should Pneumococcal Serotype 3 Be Included in Serotype-Specific Immunoassays?

    Ezra Linley / Abigail Bell / Jenna F. Gritzfeld / Ray Borrow

    Vaccines, Vol 7, Iss 1, p

    2019  Volume 4

    Abstract: Since the introduction of the 13-valent pneumococcal conjugate vaccine, a number of studies have demonstrated the limited efficacy of the pneumococcal serotype 3 component of this vaccine. Evidence from seven countries (Denmark, France, Greece, Portugal, ...

    Abstract Since the introduction of the 13-valent pneumococcal conjugate vaccine, a number of studies have demonstrated the limited efficacy of the pneumococcal serotype 3 component of this vaccine. Evidence from seven countries (Denmark, France, Greece, Portugal, Sweden, UK, US) shows limited or no effectiveness of the 13-valent pneumococcal conjugate vaccine against serotype 3 invasive pneumococcal disease and carriage. The serotype 3 capsule has some unique characteristics that may serve to explain this lack of efficacy—capsular polysaccharide is abundantly expressed, leading to a greater thickness of capsule, and free capsular polysaccharide may be released during growth. The serotype 3 component of the Luminex multiplex assay demonstrates inferior inter-laboratory reproducibility than other components and results may not be reliable. This communication outlines this evidence and discusses whether it is necessary to include serotype 3 in the assay in the future.
    Keywords Streptococcus pneumoniae ; serotype 3 ; conjugate vaccine ; multiplex ; immunoassay ; Medicine ; R
    Language English
    Publishing date 2019-01-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Towards stratified treatment of JIA

    Stephanie J.W. Shoop-Worrall / Saskia Lawson-Tovey / Lucy R. Wedderburn / Kimme L. Hyrich / Nophar Geifman / Aline Kimonyo / Alyssia McNeece / Andrew Dick / Andrew Morris / Annie Yarwood / Athimalaipet Ramanan / Bethany R. Jebson / Chris Wallace / Daniela Dastros-Pitei / Damian Tarasek / Elizabeth Ralph / Emil Carlsson / Emily Robinson / Emma Sumner /
    Fatema Merali / Fatjon Dekaj / Helen Neale / Hussein Al-Mossawi / Jacqui Roberts / Jenna F. Gritzfeld / Joanna Fairlie / John Bowes / John Ioannou / Melissa Kartawinata / Melissa Tordoff / Michael Barnes / Michael W. Beresford / Michael Stadler / Paul Martin / Rami Kallala / Sandra Ng / Samantha Smith / Sarah Clarke / Soumya Raychaudhuri / Stephen Eyre / Sumanta Mukherjee / Teresa Duerr / Thierry Sornasse / Vasiliki Alexiou / Victoria J. Burton / Wei-Yu Lin / Wendy Thomson / Zoe Wanstall

    EBioMedicine, Vol 100, Iss , Pp 104946- (2024)

    machine learning identifies subtypes in response to methotrexate from four UK cohortsResearch in context

    2024  

    Abstract: Summary: Background: Methotrexate (MTX) is the gold-standard first-line disease-modifying anti-rheumatic drug for juvenile idiopathic arthritis (JIA), despite only being either effective or tolerated in half of children and young people (CYP). To ... ...

    Abstract Summary: Background: Methotrexate (MTX) is the gold-standard first-line disease-modifying anti-rheumatic drug for juvenile idiopathic arthritis (JIA), despite only being either effective or tolerated in half of children and young people (CYP). To facilitate stratified treatment of early JIA, novel methods in machine learning were used to i) identify clusters with distinct disease patterns following MTX initiation; ii) predict cluster membership; and iii) compare clusters to existing treatment response measures. Methods: Discovery and verification cohorts included CYP who first initiated MTX before January 2018 in one of four UK multicentre prospective cohorts of JIA within the CLUSTER consortium. JADAS components (active joint count, physician (PGA) and parental (PGE) global assessments, ESR) were recorded at MTX start and over the following year.Clusters of MTX ‘response’ were uncovered using multivariate group-based trajectory modelling separately in discovery and verification cohorts. Clusters were compared descriptively to ACR Pedi 30/90 scores, and multivariate logistic regression models predicted cluster-group assignment. Findings: The discovery cohorts included 657 CYP and verification cohorts 1241 CYP. Six clusters were identified: Fast improvers (11%), Slow Improvers (16%), Improve-Relapse (7%), Persistent Disease (44%), Persistent PGA (8%) and Persistent PGE (13%), the latter two characterised by improvement in all features except one. Factors associated with clusters included ethnicity, ILAR category, age, PGE, and ESR scores at MTX start, with predictive model area under the curve values of 0.65–0.71. Singular ACR Pedi 30/90 scores at 6 and 12 months could not capture speeds of improvement, relapsing courses or diverging disease patterns. Interpretation: Six distinct patterns following initiation of MTX have been identified using methods in artificial intelligence. These clusters demonstrate the limitations in traditional yes/no treatment response assessment (e.g., ACRPedi30) and can form the basis ...
    Keywords Juvenile idiopathic arthritis ; Machine learning ; Treatment outcome ; Epidemiology ; Methotrexate ; Medicine ; R ; Medicine (General) ; R5-920
    Subject code 310
    Language English
    Publishing date 2024-02-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: The nose is the best niche for detection of experimental pneumococcal colonisation in adults of all ages, using nasal wash

    Elissavet Nikolaou / Esther L. German / Annie Blizard / Ashleigh Howard / Lisa Hitchins / Tao Chen / Jim Chadwick / Sherin Pojar / Elena Mitsi / Carla Solórzano / Syba Sunny / Felicity Dunne / Jenna F. Gritzfeld / Hugh Adler / Jason Hinds / Katherine A. Gould / Jamie Rylance / Andrea M. Collins / Stephen B. Gordon /
    Daniela M. Ferreira

    Scientific Reports, Vol 11, Iss 1, Pp 1-

    2021  Volume 9

    Abstract: Abstract Previous studies have suggested that the pneumococcal niche changes from the nasopharynx to the oral cavity with age. We use an Experimental Human Pneumococcal Challenge model to investigate pneumococcal colonisation in different anatomical ... ...

    Abstract Abstract Previous studies have suggested that the pneumococcal niche changes from the nasopharynx to the oral cavity with age. We use an Experimental Human Pneumococcal Challenge model to investigate pneumococcal colonisation in different anatomical niches with age. Healthy adults (n = 112) were intranasally inoculated with Streptococcus pneumoniae serotype 6B (Spn6B) and were categorised as young 18–55 years (n = 57) or older > 55 years (n = 55). Colonisation status (frequency and density) was determined by multiplex qPCR targeting the lytA and cpsA-6A/B genes in both raw and culture-enriched nasal wash and oropharyngeal swab samples collected at 2-, 7- and 14-days post-exposure. For older adults, raw and culture-enriched saliva samples were also assessed. 64% of NW samples and 54% of OPS samples were positive for Spn6B in young adults, compared to 35% of NW samples, 24% of OPS samples and 6% of saliva samples in older adults. Many colonisation events were only detected in culture-enriched samples. Experimental colonisation was detected in 72% of young adults by NW and 63% by OPS. In older adults, this was 51% by NW, 36% by OPS and 9% by saliva. The nose, as assessed by nasal wash, is the best niche for detection of experimental pneumococcal colonisation in both young and older adults.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2021-09-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Impact of experimental human pneumococcal carriage on nasopharyngeal bacterial densities in healthy adults.

    Joshua R Shak / Amelieke J H Cremers / Jenna F Gritzfeld / Marien I de Jonge / Peter W M Hermans / Jorge E Vidal / Keith P Klugman / Stephen B Gordon

    PLoS ONE, Vol 9, Iss 6, p e

    2014  Volume 98829

    Abstract: Colonization of the nasopharynx by Streptococcus pneumoniae is a necessary precursor to pneumococcal diseases that result in morbidity and mortality worldwide. The nasopharynx is also host to other bacterial species, including the common pathogens ... ...

    Abstract Colonization of the nasopharynx by Streptococcus pneumoniae is a necessary precursor to pneumococcal diseases that result in morbidity and mortality worldwide. The nasopharynx is also host to other bacterial species, including the common pathogens Staphylococcus aureus, Haemophilus influenzae, and Moraxella catarrhalis. To better understand how these bacteria change in relation to pneumococcal colonization, we used species-specific quantitative PCR to examine bacterial densities in 52 subjects 7 days before, and 2, 7, and 14 days after controlled inoculation of healthy human adults with S. pneumoniae serotype 6B. Overall, 33 (63%) of subjects carried S. pneumoniae post-inoculation. The baseline presence and density of S. aureus, H. influenzae, and M. catarrhalis were not statistically associated with likelihood of successful pneumococcal colonization at this study's sample size, although a lower rate of pneumococcal colonization in the presence of S. aureus (7/14) was seen compared to that in the presence of H. influenzae (12/16). Among subjects colonized with pneumococci, the number also carrying either H. influenzae or S. aureus fell during the study and at 14 days post-inoculation, the proportion carrying S. aureus was significantly lower among those who were colonized with S. pneumoniae (p = 0.008) compared to non-colonized subjects. These data on bacterial associations are the first to be reported surrounding experimental human pneumococcal colonization and show that co-colonizing effects are likely subtle rather than absolute.
    Keywords Medicine ; R ; Science ; Q
    Subject code 572
    Language English
    Publishing date 2014-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Experimental human pneumococcal carriage augments IL-17A-dependent T-cell defence of the lung.

    Adam K A Wright / Mathieu Bangert / Jenna F Gritzfeld / Daniela M Ferreira / Kondwani C Jambo / Angela D Wright / Andrea M Collins / Stephen B Gordon

    PLoS Pathogens, Vol 9, Iss 3, p e

    2013  Volume 1003274

    Abstract: Pneumococcal carriage is both immunising and a pre-requisite for mucosal and systemic disease. Murine models of pneumococcal colonisation show that IL-17A-secreting CD4(+) T-cells (Th-17 cells) are essential for clearance of pneumococci from the ... ...

    Abstract Pneumococcal carriage is both immunising and a pre-requisite for mucosal and systemic disease. Murine models of pneumococcal colonisation show that IL-17A-secreting CD4(+) T-cells (Th-17 cells) are essential for clearance of pneumococci from the nasopharynx. Pneumococcal-responding IL-17A-secreting CD4(+) T-cells have not been described in the adult human lung and it is unknown whether they can be elicited by carriage and protect the lung from pneumococcal infection. We investigated the direct effect of experimental human pneumococcal nasal carriage (EHPC) on the frequency and phenotype of cognate CD4(+) T-cells in broncho-alveolar lavage and blood using multi-parameter flow cytometry. We then examined whether they could augment ex vivo alveolar macrophage killing of pneumococci using an in vitro assay. We showed that human pneumococcal carriage leads to a 17.4-fold (p = 0.007) and 8-fold (p = 0.003) increase in the frequency of cognate IL-17A(+) CD4(+) T-cells in BAL and blood, respectively. The phenotype with the largest proportion were TNF(+)/IL-17A(+) co-producing CD4(+) memory T-cells (p<0.01); IFNγ(+) CD4(+) memory T-cells were not significantly increased following carriage. Pneumococci could stimulate large amounts of IL-17A protein from BAL cells in the absence of carriage but in the presence of cognate CD4(+) memory T-cells, IL-17A protein levels were increased by a further 50%. Further to this we then show that alveolar macrophages, which express IL-17A receptors A and C, showed enhanced killing of opsonised pneumococci when stimulated with rhIL-17A (p = 0.013). Killing negatively correlated with RC (r = -0.9, p = 0.017) but not RA expression. We conclude that human pneumococcal carriage can increase the proportion of lung IL-17A-secreting CD4(+) memory T-cells that may enhance innate cellular immunity against pathogenic challenge. These pathways may be utilised to enhance vaccine efficacy to protect the lung against pneumonia.
    Keywords Immunologic diseases. Allergy ; RC581-607 ; Biology (General) ; QH301-705.5
    Subject code 570
    Language English
    Publishing date 2013-03-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Novel Analysis of Immune Cells from Nasal Microbiopsy Demonstrates Reliable, Reproducible Data for Immune Populations, and Superior Cytokine Detection Compared to Nasal Wash.

    Simon P Jochems / Katherine Piddock / Jamie Rylance / Hugh Adler / Beatriz F Carniel / Andrea Collins / Jenna F Gritzfeld / Carole Hancock / Helen Hill / Jesus Reiné / Alexandra Seddon / Carla Solórzano / Syba Sunny / Ashleigh Trimble / Angela D Wright / Seher Zaidi / Stephen B Gordon / Daniela M Ferreira

    PLoS ONE, Vol 12, Iss 1, p e

    2017  Volume 0169805

    Abstract: The morbidity and mortality related to respiratory tract diseases is enormous, with hundreds of millions of individuals afflicted and four million people dying each year. Understanding the immunological processes in the mucosa that govern outcome ... ...

    Abstract The morbidity and mortality related to respiratory tract diseases is enormous, with hundreds of millions of individuals afflicted and four million people dying each year. Understanding the immunological processes in the mucosa that govern outcome following pathogenic encounter could lead to novel therapies. There is a need to study responses at mucosal surfaces in humans for two reasons: (i) Immunological findings in mice, or other animals, often fail to translate to humans. (ii) Compartmentalization of the immune system dictates a need to study sites where pathogens reside. In this manuscript, we describe two novel non-invasive nasal mucosal microsampling techniques and their use for measuring immunological parameters: 1) using nasal curettes to collect cells from the inferior turbinate and; 2) absorptive matrices to collect nasal lining fluid. Both techniques were well tolerated and yielded reproducible and robust data. We demonstrated differences in immune populations and activation state in nasal mucosa compared to blood as well as compared to nasopharyngeal lumen in healthy adults. We also found superior cytokine detection with absorptive matrices compared to nasal wash. These techniques are promising new tools that will facilitate studies of the immunological signatures underlying susceptibility and resistance to respiratory infections.
    Keywords Medicine ; R ; Science ; Q
    Subject code 610
    Language English
    Publishing date 2017-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Human nasal challenge with Streptococcus pneumoniae is immunising in the absence of carriage.

    Adam K A Wright / Daniela M Ferreira / Jenna F Gritzfeld / Angela D Wright / Kathryn Armitage / Kondwani C Jambo / Emily Bate / Sherouk El Batrawy / Andrea Collins / Stephen B Gordon

    PLoS Pathogens, Vol 8, Iss 4, p e

    2012  Volume 1002622

    Abstract: Infectious challenge of the human nasal mucosa elicits immune responses that determine the fate of the host-bacterial interaction; leading either to clearance, colonisation and/or disease. Persistent antigenic exposure from pneumococcal colonisation can ... ...

    Abstract Infectious challenge of the human nasal mucosa elicits immune responses that determine the fate of the host-bacterial interaction; leading either to clearance, colonisation and/or disease. Persistent antigenic exposure from pneumococcal colonisation can induce both humoral and cellular defences that are protective against carriage and disease. We challenged healthy adults intra-nasally with live 23F or 6B Streptococcus pneumoniae in two sequential cohorts and collected nasal wash, bronchoalveolar lavage (BAL) and blood before and 6 weeks after challenge. We hypothesised that both cohorts would successfully become colonised but this did not occur except for one volunteer. The effect of bacterial challenge without colonisation in healthy adults has not been previously assessed. We measured the antigen-specific humoral and cellular immune responses in challenged but not colonised volunteers by ELISA and Flow Cytometry. Antigen-specific responses were seen in each compartment both before and after bacterial challenge for both cohorts. Antigen-specific IgG and IgA levels were significantly elevated in nasal wash 6 weeks after challenge compared to baseline. Immunoglobulin responses to pneumococci were directed towards various protein targets but not capsular polysaccharide. 23F but not 6B challenge elevated IgG anti-PspA in BAL. Serum immunoglobulins did not increase in response to challenge. In neither challenge cohort was there any alteration in the frequencies of TNF, IL-17 or IFNγ producing CD4 T cells before or after challenge in BAL or blood. We show that simple, low dose mucosal exposure with pneumococci may immunise mucosal surfaces by augmenting anti-protein immunoglobulin responses; but not capsular or cellular responses. We hypothesise that mucosal exposure alone may not replicate the systemic immunising effect of experimental or natural carriage in humans.
    Keywords Immunologic diseases. Allergy ; RC581-607 ; Biology (General) ; QH301-705.5
    Subject code 610
    Language English
    Publishing date 2012-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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