n vivo characterization of Acinetobacter baumannii lung infection in a mouse model

  • Thomas ROUMA

    Student thesis: Master typesMaster in biochemistry and molecular and cell biology, Professional focus

    Abstract

    Acinetobacter baumannii is an opportunistic bacterial pathogen frequently causing nosocomial infection, mostly pneumonia and bacteraemia, in immunocompromised individuals. The case of this bacteria is particularly alarming due to its multi-drug resistance phenotype. In order to overcome the lack of effective treatment, vaccination of people planning to stay in a hospital can be considered. Currently no vaccines are available and immune response against this pathogen is poorly known.
    In order to better characterize the protective immune response against A. baumannii, we set up a model of lung infection in wild-type mice and mice genetically deficient for key component of immune system.
    Intranasal inoculations were performed with the LAC-4 and the AB5075 strains, two highly virulent clinical isolate. Experiments highlighted the key role of gamma-delta T cells and T Helper (Th)1 and Th17 responses, through the involvement of IL-12p35 and IL-17RA, in the control of primary infection.
    We also developed a vaccination model to study the development of protective immune memory against A. baumannii.Inactivated vaccine composed of heat killed (HK) bacteria, appears able to induce the development of a protective immune memory in wild type mice but also in mice deficient for cellular (CD4+T cells, T cells) and humoral (B cells) parts of the immune response. These results suggest that vaccination with HK bacteria induces the development of a protective memory based on multiple and redundant effectors mechanisms.
    Together, our results suggest that inactivated vaccines may induce protection against A. baumannii in partially immunosuppressed individuals.
    Date of AwardJan 2022
    Original languageEnglish
    Awarding Institution
    • University of Namur
    SupervisorEric Muraille (Supervisor) & Xavier De Bolle (Co-Supervisor)

    Cite this

    '