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Nicole Guiso - One of the best experts on this subject based on the ideXlab platform.

  • Pertactin-Negative and Filamentous Hemagglutinin-Negative Bordetella Pertussis, Australia, 2013–2017
    'Centers for Disease Control and Prevention (CDC)', 2019
    Co-Authors: Sophie Octavia, Nicole Guiso, Laurence Don Wai Luu, Michael Payne, Verlaine Timms, Chin Yen Tay, Anthony D. Keil, Vitali Sintchenko, Ruiting Lan
    Abstract:

    During the 2008–2012 Pertussis epidemic in Australia, pertactin (Prn)–negative Bordetella Pertussis emerged. We analyzed 78 isolates from the 2013–2017 epidemic and documented continued expansion of Prn-negative ptxP3 B. Pertussis strains. We also detected a filamentous hemagglutinin-negative and Prn-negative B. Pertussis isolate

  • New Data on Vaccine Antigen Deficient Bordetella Pertussis Isolates.
    Vaccines, 2015
    Co-Authors: Valérie Bouchez, Elisabeth Njamkepo, Nicolas Hegerle, Francesco Strati, Nicole Guiso
    Abstract:

    Evolution of Bordetella Pertussis is driven by natural and vaccine pressures. Isolates circulating in regions with high vaccination coverage present multiple allelic and antigenic variations as compared to isolates collected before introduction of vaccination. Furthermore, during the last epidemics reported in regions using Pertussis acellular vaccines, isolates deficient for vaccine antigens, such as pertactin (PRN), were reported to reach high proportions of circulating isolates. More sporadic filamentous hemagglutinin (FHA) or Pertussis toxin (PT) deficient isolates were also collected. The whole genome of some recent French isolates, deficient or non-deficient in vaccine antigens, were analyzed. Transcription profiles of the expression of the main virulence factors were also compared. The invasive phenotype in an in vitro human tracheal epithelial (HTE) cell model of infection was evaluated. Our genomic analysis focused on SNPs related to virulence genes known to be more likely to present allelic polymorphism. Transcriptomic data indicated that isolates circulating since the introduction of Pertussis vaccines present lower transcription levels of the main virulence genes than the isolates of the pre-vaccine era. Furthermore, isolates not producing FHA present significantly higher expression levels of the entire set of genes tested. Finally, we observed that recent isolates are more invasive in HTE cells when compared to the reference strain, but no multiplication occurs within cells.

  • rapid increase in pertactin deficient Bordetella Pertussis isolates australia
    Emerging Infectious Diseases, 2014
    Co-Authors: Connie Lam, Nicole Guiso, Helen Marshall, Peter Mcintyre, Sophie Octavia, Vitali Sintchenko, Lawrence Ricafort, Gwendolyn L Gilbert, Nicholas Wood, Anthony D. Keil
    Abstract:

    Acellular vaccines against Bordetella Pertussis were introduced in Australia in 1997. By 2000, these vaccines had replaced whole-cell vaccines. During 2008–2012, a large outbreak of Pertussis occurred. During this period, 30% (96/320) of B. Pertussis isolates did not express the vaccine antigen pertactin (Prn). Multiple mechanisms of Prn inactivation were documented, including IS481 and IS1002 disruptions, a variation within a homopolymeric tract, and deletion of the prn gene. The mechanism of lack of expression of Prn in 16 (17%) isolates could not be determined at the sequence level. These findings suggest that B. Pertussis not expressing Prn arose independently multiple times since 2008, rather than by expansion of a single Prnnegative clone. All but 1 isolate had ptxA1, prn2, and ptxP3, the alleles representative of currently circulating strains in Australia. This pattern is consistent with continuing evolution of B. Pertussis in response to vaccine selection pressure.

  • Bordetella Pertussis why is it still circulating
    Journal of Infection, 2014
    Co-Authors: Nicole Guiso
    Abstract:

    Summary Bordetella Pertussis is the causal agent of whooping cough, a highly contagious respiratory disease that is life-threatening in infants under the age of three months and may also be very severe in pregnant women and seniors. This disease can be prevented by vaccination but it remains a public health problem in many developed and developing countries. 1 So, why is B. Pertussis still circulating? We need to consider several aspects of this vaccine-preventable disease when answering this question: (i) the history of the disease and the historical context in which the vaccine was developed; (ii) the type of vaccine used; (iii) the vaccination strategy and coverage; (iv) the disease surveillance after the introduction of generalized vaccination and (v) the surveillance for the causal agent of the disease.

  • virulence of pertactin negative Bordetella Pertussis isolates from infants france
    Emerging Infectious Diseases, 2013
    Co-Authors: Helene Bodilis, Nicole Guiso
    Abstract:

    Bordetella Pertussis isolates that do not express pertactin (PRN) are increasing in regions where acellular Pertussis vaccines have been used for >7 years. We analyzed data from France and compared clinical symptoms among infants <6 months old infected by PRN-positive or PRN-negative isolates. No major clinical differences were found between the 2 groups.

Daniel Ladant - One of the best experts on this subject based on the ideXlab platform.

  • Bioengineering of Bordetella Pertussis Adenylate Cyclase Toxin for Vaccine Development and Other Biotechnological Purposes
    Toxins, 2021
    Co-Authors: Daniel Ladant
    Abstract:

    The adenylate cyclase toxin, CyaA, is one of the key virulent factors produced by Bordetella Pertussis, the causative agent of whooping cough. This toxin primarily targets innate immunity to facilitate bacterial colonization of the respiratory tract. CyaA exhibits several remarkable characteristics that have been exploited for various applications in vaccinology and other biotechnological purposes. CyaA has been engineered as a potent vaccine vehicle to deliver antigens into antigen-presenting cells, while the adenylate cyclase catalytic domain has been used to design a robust genetic assay for monitoring protein-protein interactions in bacteria. These two biotechnological applications are briefly summarized in this chapter.

  • interaction of Bordetella Pertussis adenylate cyclase with cd11b cd18 role of toxin acylation and identification of the main integrin interaction domain
    Journal of Biological Chemistry, 2003
    Co-Authors: Mohammed Elazamielidrissi, Daniel Ladant, Cecile Bauche, Jirina Loucka, Radim Osicka, Peter Sebo, Claude Leclerc
    Abstract:

    Adenylate cyclase toxin (CyaA) is one of the major virulence factors produced by Bordetella Pertussis, the whooping cough agent. CyaA belongs to the repeat in toxin protein family and requires a post-translational fatty acylation to form cation-selective channels in target cell membranes and to penetrate into cytosol. We have demonstrated recently that CyaA uses the αMβ2 integrin (CD11b/CD18) as a specific cellular receptor. Here we show that the acylation of CyaA is required for a productive and tight interaction of the toxin with cells expressing CD11b. In addition, we demonstrate that the catalytic domain is not required for binding of CyaA to CD11b and that the main integrin interacting domain of CyaA is located in its glycine/aspartate-rich repeat region. These data decipher, for the first time, the interaction of CyaA with CD11b-positive cells and open new prospects for understanding the interaction of Bordetella Pertussis with innate and adaptive immune systems.

  • Bordetella Pertussis adenylate cyclase a toxin with multiple talents
    Trends in Microbiology, 1999
    Co-Authors: Daniel Ladant, Agnes Ullmann
    Abstract:

    Abstract Bordetella Pertussis secretes a calmodulin-activated adenylate cyclase toxin (CyaA) that is able to deliver its amino-terminal catalytic domain into the cytosol of eukaryotic cells. The novelty of the structural organization and conformational flexibility of the CyaA catalytic domain has opened up the way for exploiting this protein as a tool for several biological applications, including epitope delivery, protein targeting and characterization of protein–protein interactions.

Qurban Hussain - One of the best experts on this subject based on the ideXlab platform.

  • Monospecific antibody against Bordetella Pertussis Adenylate Cyclase protects from Pertussis
    2020
    Co-Authors: Faiz Yasmeen, Yasmeen Faiz Kazi, Qurban Hussain
    Abstract:

    ABSTRACT Objectives: Acellular Pertussis vaccines has been largely accepted world-wide however, there are reports about limited antibody response against these vaccines suggesting that multiple antigens should be included in acellular vaccines to attain full protection. The aim of present study was to evaluate the role of Bordetella Pertussis adenylate cyclase as a protective antigen. Materials and methods: Highly mono-specific antibody against adenylate cyclase (AC) was raised in rabbits using nitrocellulose bound adenylate cyclase and the specificity was assessed by immuoblotting. B.Pertussis 18-323, was incubated with the mono-specific serum and without serum as a control. Mice were challenged intra-nasally and pathophysiolgical responses were recorded. Results: The production of B.Pertussis adenylate cyclase monospecific antibody that successfully recognized on immunoblot and gave protection against fatality (p< 0.01) and lung consolidation (p <0.01). Mouse weight gain showed significant difference (p< 0.05). Conclusio

  • monospecific antibody against Bordetella Pertussis adenylate cyclase protects from Pertussis
    Journal of Microbiology and Infectious Diseases, 2012
    Co-Authors: Yasmeen Faiz Kazi, Qurban Hussain
    Abstract:

    Objectives: Acellular Pertussis vaccines has been largely accepted world-wide however, there are reports about limited antibody response against these vaccines suggesting that multiple antigens should be included in acellular vaccines to attain full protection. The aim of present study was to evaluate the role of Bordetella Pertussis adenylate cyclase as a protective antigen. Materials and methods: Highly mono-specific antibody against adenylate cyclase (AC) was raised in rabbits using nitrocellulose bound adenylate cyclase and the specificity was assessed by immuoblotting. B.Pertussis 18-323, was incubated with the mono-specific serum and without serum as a control. Mice were challenged intra-nasally and patho physiolgical responses were recorded. Results: The production of B.Pertussis adenylate cyclase monospecific antibody that successfully recognized on im munoblot and gave protection against fatality (p< 0.01) and lung consolidation (p <0.01). Mouse weight gain showed significant difference (p< 0.05). Conclusion: These preliminary results highlight the role of the B.Pertussis adenylate cyclase as a potential Pertussis vaccine candidate. B.Pertussis AC exhibited significant protection against Pertussis in murine model. J Microbiol Infect Dis 2012; 2(2): 36-43

Agnes Ullmann - One of the best experts on this subject based on the ideXlab platform.

  • Bordetella Pertussis adenylate cyclase a toxin with multiple talents
    Trends in Microbiology, 1999
    Co-Authors: Daniel Ladant, Agnes Ullmann
    Abstract:

    Abstract Bordetella Pertussis secretes a calmodulin-activated adenylate cyclase toxin (CyaA) that is able to deliver its amino-terminal catalytic domain into the cytosol of eukaryotic cells. The novelty of the structural organization and conformational flexibility of the CyaA catalytic domain has opened up the way for exploiting this protein as a tool for several biological applications, including epitope delivery, protein targeting and characterization of protein–protein interactions.

Yasmeen Faiz Kazi - One of the best experts on this subject based on the ideXlab platform.

  • Monospecific antibody against Bordetella Pertussis Adenylate Cyclase protects from Pertussis
    2020
    Co-Authors: Faiz Yasmeen, Yasmeen Faiz Kazi, Qurban Hussain
    Abstract:

    ABSTRACT Objectives: Acellular Pertussis vaccines has been largely accepted world-wide however, there are reports about limited antibody response against these vaccines suggesting that multiple antigens should be included in acellular vaccines to attain full protection. The aim of present study was to evaluate the role of Bordetella Pertussis adenylate cyclase as a protective antigen. Materials and methods: Highly mono-specific antibody against adenylate cyclase (AC) was raised in rabbits using nitrocellulose bound adenylate cyclase and the specificity was assessed by immuoblotting. B.Pertussis 18-323, was incubated with the mono-specific serum and without serum as a control. Mice were challenged intra-nasally and pathophysiolgical responses were recorded. Results: The production of B.Pertussis adenylate cyclase monospecific antibody that successfully recognized on immunoblot and gave protection against fatality (p< 0.01) and lung consolidation (p <0.01). Mouse weight gain showed significant difference (p< 0.05). Conclusio

  • monospecific antibody against Bordetella Pertussis adenylate cyclase protects from Pertussis
    Journal of Microbiology and Infectious Diseases, 2012
    Co-Authors: Yasmeen Faiz Kazi, Qurban Hussain
    Abstract:

    Objectives: Acellular Pertussis vaccines has been largely accepted world-wide however, there are reports about limited antibody response against these vaccines suggesting that multiple antigens should be included in acellular vaccines to attain full protection. The aim of present study was to evaluate the role of Bordetella Pertussis adenylate cyclase as a protective antigen. Materials and methods: Highly mono-specific antibody against adenylate cyclase (AC) was raised in rabbits using nitrocellulose bound adenylate cyclase and the specificity was assessed by immuoblotting. B.Pertussis 18-323, was incubated with the mono-specific serum and without serum as a control. Mice were challenged intra-nasally and patho physiolgical responses were recorded. Results: The production of B.Pertussis adenylate cyclase monospecific antibody that successfully recognized on im munoblot and gave protection against fatality (p< 0.01) and lung consolidation (p <0.01). Mouse weight gain showed significant difference (p< 0.05). Conclusion: These preliminary results highlight the role of the B.Pertussis adenylate cyclase as a potential Pertussis vaccine candidate. B.Pertussis AC exhibited significant protection against Pertussis in murine model. J Microbiol Infect Dis 2012; 2(2): 36-43