Understanding vaccine induced protective immunity to Mycobacterium tuberculosis

The current worldwide epidemic of <em>Mycobacterium tuberculosis</em> infection is a huge global health problem. Widespread BCG vaccination remains a useful tool in combating this epidemic; however, its variable efficacy requires urgent development of novel vaccines against <em>Myc...

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Main Author: Ronan, E
Other Authors: Beverley, P
Format: Thesis
Language:English
Published: 2011
Subjects:
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author Ronan, E
author2 Beverley, P
author_facet Beverley, P
Ronan, E
author_sort Ronan, E
collection OXFORD
description The current worldwide epidemic of <em>Mycobacterium tuberculosis</em> infection is a huge global health problem. Widespread BCG vaccination remains a useful tool in combating this epidemic; however, its variable efficacy requires urgent development of novel vaccines against <em>Mycobacterium tuberculosis</em>. Such a candidate vaccine is a serotype 5 adenovirus expressing antigen 85A from <em>M. tuberculosis</em> (Ad85A). In animal models Ad85A confers significant protection when administered intra-nasally. The work in this thesis demonstrates that intra-nasal immunisation with Ad85A results in inhibition of <em>M. tuberculosis</em> growth in the lung early after infection, in contrast to the late inhibition induced by parenterally administered vaccines. Early inhibition correlates with the presence in the lung of a highly activated population of antigen-specific CD8 T cells, maintained for at least 6 months post-immunisation by persistent antigen. For intra-nasal Ad85A to be effective, the vaccine must be delivered into the lower respiratory tract, as immunisation targeting only the nasal-associated lymphoid tissue (NALT) does not result in protection. Following a change of animal facility, the lung immune response to intra-dermal immunisation with Ad85A increased and this route of immunisation now induced protection, though growth of <em>M. tuberculosis</em> was inhibited only late after infection. However, this response and protection can be altered by exposure to environmental mycobacteria. Further experiments showed that simultaneous respiratory and parenteral immunisations (SIM) act additively, where local lung immunity inhibits the growth of <em>M. tuberculosis</em> early after infection and systemic immunity protects later. SIM regimes generate greatly improved protection over either immunisation alone and do not depend on priming and boosting.
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spelling oxford-uuid:c0d7b20f-e144-42f8-aa52-301d0938b0b32022-03-27T05:57:13ZUnderstanding vaccine induced protective immunity to Mycobacterium tuberculosisThesishttp://purl.org/coar/resource_type/c_db06uuid:c0d7b20f-e144-42f8-aa52-301d0938b0b3Biology (medical sciences)Infectious diseasesImmunologyVaccinologyEnglishOxford University Research Archive - Valet2011Ronan, EBeverley, PTchilian, ESattentau, QThe current worldwide epidemic of <em>Mycobacterium tuberculosis</em> infection is a huge global health problem. Widespread BCG vaccination remains a useful tool in combating this epidemic; however, its variable efficacy requires urgent development of novel vaccines against <em>Mycobacterium tuberculosis</em>. Such a candidate vaccine is a serotype 5 adenovirus expressing antigen 85A from <em>M. tuberculosis</em> (Ad85A). In animal models Ad85A confers significant protection when administered intra-nasally. The work in this thesis demonstrates that intra-nasal immunisation with Ad85A results in inhibition of <em>M. tuberculosis</em> growth in the lung early after infection, in contrast to the late inhibition induced by parenterally administered vaccines. Early inhibition correlates with the presence in the lung of a highly activated population of antigen-specific CD8 T cells, maintained for at least 6 months post-immunisation by persistent antigen. For intra-nasal Ad85A to be effective, the vaccine must be delivered into the lower respiratory tract, as immunisation targeting only the nasal-associated lymphoid tissue (NALT) does not result in protection. Following a change of animal facility, the lung immune response to intra-dermal immunisation with Ad85A increased and this route of immunisation now induced protection, though growth of <em>M. tuberculosis</em> was inhibited only late after infection. However, this response and protection can be altered by exposure to environmental mycobacteria. Further experiments showed that simultaneous respiratory and parenteral immunisations (SIM) act additively, where local lung immunity inhibits the growth of <em>M. tuberculosis</em> early after infection and systemic immunity protects later. SIM regimes generate greatly improved protection over either immunisation alone and do not depend on priming and boosting.
spellingShingle Biology (medical sciences)
Infectious diseases
Immunology
Vaccinology
Ronan, E
Understanding vaccine induced protective immunity to Mycobacterium tuberculosis
title Understanding vaccine induced protective immunity to Mycobacterium tuberculosis
title_full Understanding vaccine induced protective immunity to Mycobacterium tuberculosis
title_fullStr Understanding vaccine induced protective immunity to Mycobacterium tuberculosis
title_full_unstemmed Understanding vaccine induced protective immunity to Mycobacterium tuberculosis
title_short Understanding vaccine induced protective immunity to Mycobacterium tuberculosis
title_sort understanding vaccine induced protective immunity to mycobacterium tuberculosis
topic Biology (medical sciences)
Infectious diseases
Immunology
Vaccinology
work_keys_str_mv AT ronane understandingvaccineinducedprotectiveimmunitytomycobacteriumtuberculosis