Liver-stage vaccines for malaria

The development of an efficacious <em>P. falciparum</em> malaria vaccine remains a top priority. Pre-erythrocytic vaccine efforts have traditionally focussed on two well- known antigens, CSP and TRAP, yet thousands of antigens are expressed throughout the liver-stage. The work described...

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Glavni avtor: Longley, RJ
Drugi avtorji: Hill, A
Format: Thesis
Jezik:English
Izdano: 2013
Teme:
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author Longley, RJ
author2 Hill, A
author_facet Hill, A
Longley, RJ
author_sort Longley, RJ
collection OXFORD
description The development of an efficacious <em>P. falciparum</em> malaria vaccine remains a top priority. Pre-erythrocytic vaccine efforts have traditionally focussed on two well- known antigens, CSP and TRAP, yet thousands of antigens are expressed throughout the liver-stage. The work described in this thesis aimed to assess the ability of other pre-erythrocytic antigens to induce an immune response and provide protective efficacy against transgenic parasites in a mouse model. Research undertaken in our laboratory has demonstrated the ability of prime-boost viral vectored sub-unit vaccination regimens to elicit high levels of antigen-specific T cells. Eight candidate antigens were therefore expressed individually in the viral vectors ChAd63 and MVA. Two antigens, PfLSA1 and PfLSAP2, were identified that confer greater protective efficacy in inbred mice than either CSP or TRAP. PfLSA1 was also able to induce almost complete sterile efficacy in outbred mice, suggesting this vaccine should be assessed in a clinical trial. Immune responses to the candidate antigens were also assessed in human volunteers following their first exposure to controlled malaria infection. The antigen TRAP was further characterised by epitope mapping in volunteers vaccinated with ChAd63-MVA ME-TRAP. However, no functional T cell assay exists to measure inhibition of <em>P. falciparum</em> liver-stage parasites. An improved murine <em>in vitro</em> T cell killing assay was developed, and preliminary experiments were conducted that demonstrate the potential and promise of a <em>P. falciparum</em> T cell killing assay. Such assays will not only allow mechanistic studies to be undertaken, but could also change the way we screen pre-clinical liver-stage vaccines.
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spelling oxford-uuid:b5c9821c-db32-4b66-a315-02541e62f5662024-03-11T11:16:22ZLiver-stage vaccines for malariaThesishttp://purl.org/coar/resource_type/c_db06uuid:b5c9821c-db32-4b66-a315-02541e62f566Biology (medical sciences)ImmunologyParasitologyMalariaInfectious diseasesEnglishOxford University Research Archive - Valet2013Longley, RJHill, ASpencer, AEwer, KThe development of an efficacious <em>P. falciparum</em> malaria vaccine remains a top priority. Pre-erythrocytic vaccine efforts have traditionally focussed on two well- known antigens, CSP and TRAP, yet thousands of antigens are expressed throughout the liver-stage. The work described in this thesis aimed to assess the ability of other pre-erythrocytic antigens to induce an immune response and provide protective efficacy against transgenic parasites in a mouse model. Research undertaken in our laboratory has demonstrated the ability of prime-boost viral vectored sub-unit vaccination regimens to elicit high levels of antigen-specific T cells. Eight candidate antigens were therefore expressed individually in the viral vectors ChAd63 and MVA. Two antigens, PfLSA1 and PfLSAP2, were identified that confer greater protective efficacy in inbred mice than either CSP or TRAP. PfLSA1 was also able to induce almost complete sterile efficacy in outbred mice, suggesting this vaccine should be assessed in a clinical trial. Immune responses to the candidate antigens were also assessed in human volunteers following their first exposure to controlled malaria infection. The antigen TRAP was further characterised by epitope mapping in volunteers vaccinated with ChAd63-MVA ME-TRAP. However, no functional T cell assay exists to measure inhibition of <em>P. falciparum</em> liver-stage parasites. An improved murine <em>in vitro</em> T cell killing assay was developed, and preliminary experiments were conducted that demonstrate the potential and promise of a <em>P. falciparum</em> T cell killing assay. Such assays will not only allow mechanistic studies to be undertaken, but could also change the way we screen pre-clinical liver-stage vaccines.
spellingShingle Biology (medical sciences)
Immunology
Parasitology
Malaria
Infectious diseases
Longley, RJ
Liver-stage vaccines for malaria
title Liver-stage vaccines for malaria
title_full Liver-stage vaccines for malaria
title_fullStr Liver-stage vaccines for malaria
title_full_unstemmed Liver-stage vaccines for malaria
title_short Liver-stage vaccines for malaria
title_sort liver stage vaccines for malaria
topic Biology (medical sciences)
Immunology
Parasitology
Malaria
Infectious diseases
work_keys_str_mv AT longleyrj liverstagevaccinesformalaria