Assessment of anti-merozoite antibody function in the context of blood-stage malaria vaccine development

<p>In regions endemic for malaria, natural exposure results in an acquired immunity which protects individuals from severe disease. However, no vaccine against the blood-stage of malaria, against which naturally-acquired immunity is targeted, currently exists that is capable of emulating, or o...

Full description

Bibliographic Details
Main Author: Llewellyn, D
Other Authors: Draper, S
Format: Thesis
Language:English
Published: 2014
Subjects:
_version_ 1797075551081463808
author Llewellyn, D
author2 Draper, S
author_facet Draper, S
Llewellyn, D
author_sort Llewellyn, D
collection OXFORD
description <p>In regions endemic for malaria, natural exposure results in an acquired immunity which protects individuals from severe disease. However, no vaccine against the blood-stage of malaria, against which naturally-acquired immunity is targeted, currently exists that is capable of emulating, or out-performing, natural protection. To rationally direct the next generation of blood-stage malaria vaccine development, a greater understanding of the immunological mechanisms involved in clinical protection is required.</p> <p>To date, the assessment of naturally-acquired and vaccine-induced immunity to the blood-stage of malaria has suffered from a paucity of <em>in vitro</em> immunological assays that are both robust and reproducible, whilst allowing for assessment of anti-parasitic activity induced by antibodies, either alone, or in conjunction with immune cells. Thus this Thesis describes the development of the antibody-dependent respiratory burst (ADRB) assay, for assessment of blood-stage immunity against <em>Plasmodium falciparum</em>, as well as the Duffy antigen receptor for chemokines (DARC) – Duffy binding protein (DBP) binding inhibition assay, for assessing antibody mediated immunity to <em>P. vivax</em>. A reproducible and standardised assay of ADRB activity was developed here and applied to studies of immunity in both mice and humans. ADRB activity, which assesses antibodies' ability to activate oxidative burst in neutrophils via Fc receptor (FcR)-dependent pathways, was shown to associate with clinical protection in a cohort from Mali where FcR-independent immunological assays, such as the assay of growth inhibition activity, did not. This work thus elucidates the importance of FcR-dependent immunity to <em>P. falciparum</em> malaria and establishes the ADRB assay as a useful tool for future vaccine development. In addition, the DARC-DBP binding inhibition assay was established and utilised to assess inhibitory activity of antibodies induced in the first Phase I clinical trial of this antigen. Results identify the need for significant improvements in vaccine design, and show the utility of the assay as a tool for assessing future blood-stage vaccine development efforts against this neglected parasite.</p>
first_indexed 2024-03-06T23:51:54Z
format Thesis
id oxford-uuid:72e325e5-504c-480a-8b89-6a3ecb73f699
institution University of Oxford
language English
last_indexed 2024-03-06T23:51:54Z
publishDate 2014
record_format dspace
spelling oxford-uuid:72e325e5-504c-480a-8b89-6a3ecb73f6992022-03-26T19:52:56ZAssessment of anti-merozoite antibody function in the context of blood-stage malaria vaccine developmentThesishttp://purl.org/coar/resource_type/c_db06uuid:72e325e5-504c-480a-8b89-6a3ecb73f699ImmunologyInfectious DiseaseEnglishORA Deposit2014Llewellyn, DDraper, S<p>In regions endemic for malaria, natural exposure results in an acquired immunity which protects individuals from severe disease. However, no vaccine against the blood-stage of malaria, against which naturally-acquired immunity is targeted, currently exists that is capable of emulating, or out-performing, natural protection. To rationally direct the next generation of blood-stage malaria vaccine development, a greater understanding of the immunological mechanisms involved in clinical protection is required.</p> <p>To date, the assessment of naturally-acquired and vaccine-induced immunity to the blood-stage of malaria has suffered from a paucity of <em>in vitro</em> immunological assays that are both robust and reproducible, whilst allowing for assessment of anti-parasitic activity induced by antibodies, either alone, or in conjunction with immune cells. Thus this Thesis describes the development of the antibody-dependent respiratory burst (ADRB) assay, for assessment of blood-stage immunity against <em>Plasmodium falciparum</em>, as well as the Duffy antigen receptor for chemokines (DARC) – Duffy binding protein (DBP) binding inhibition assay, for assessing antibody mediated immunity to <em>P. vivax</em>. A reproducible and standardised assay of ADRB activity was developed here and applied to studies of immunity in both mice and humans. ADRB activity, which assesses antibodies' ability to activate oxidative burst in neutrophils via Fc receptor (FcR)-dependent pathways, was shown to associate with clinical protection in a cohort from Mali where FcR-independent immunological assays, such as the assay of growth inhibition activity, did not. This work thus elucidates the importance of FcR-dependent immunity to <em>P. falciparum</em> malaria and establishes the ADRB assay as a useful tool for future vaccine development. In addition, the DARC-DBP binding inhibition assay was established and utilised to assess inhibitory activity of antibodies induced in the first Phase I clinical trial of this antigen. Results identify the need for significant improvements in vaccine design, and show the utility of the assay as a tool for assessing future blood-stage vaccine development efforts against this neglected parasite.</p>
spellingShingle Immunology
Infectious Disease
Llewellyn, D
Assessment of anti-merozoite antibody function in the context of blood-stage malaria vaccine development
title Assessment of anti-merozoite antibody function in the context of blood-stage malaria vaccine development
title_full Assessment of anti-merozoite antibody function in the context of blood-stage malaria vaccine development
title_fullStr Assessment of anti-merozoite antibody function in the context of blood-stage malaria vaccine development
title_full_unstemmed Assessment of anti-merozoite antibody function in the context of blood-stage malaria vaccine development
title_short Assessment of anti-merozoite antibody function in the context of blood-stage malaria vaccine development
title_sort assessment of anti merozoite antibody function in the context of blood stage malaria vaccine development
topic Immunology
Infectious Disease
work_keys_str_mv AT llewellynd assessmentofantimerozoiteantibodyfunctioninthecontextofbloodstagemalariavaccinedevelopment