ABSTRACT
Malaria vaccine clinical trials in exposed populations have not always been consistent in
finding robust associations between the predicted immune responses and protection
against disease. The selection of most promising vaccine candidates have been based on
direct antibody inhibition assays that have performed dismally. This suggests that such
immune correlates employed in assessing their efficacies may not be surrogate markers of
protection. Immunity to asexual blood stage malaria is complex and likely involves
multiple mechanisms. IgG antibodies are thought to play a critical role and a
corresponding reliable in vitro correlate of antibody-mediated cellular immunity has long
been sought to facilitate malaria vaccine development. The aim of present work was to
establish an effector cell antibody-dependent respiratory burst assay as a correlate of
naturally acquired immunity that may be a useful tool to evaluate vaccine-induced
immunity in malaria studies. The specific objectives of the study were: to determine if
polymorphonuclear neutrophils (PMNs) and monocytes could be triggered by malaria
merozoites to produce reactive oxygen species (ROS); to determine the minimum number
of merozoites required for the trigger; to determine the reproducibility of the assay, to
determine the applicability of the assay by testing if the blood stage malaria vaccine
candidates MSP–1, MSP–2 and AMA–1 elicited antibodies that trigger effector cell
respiratory burst, and to associate total antibody titres to respiratory burst activity after
vaccination. This study adopted an experimental design where the characteristics of the
antibody mediated effector-cell-dependent respiratory burst induction were established
and the key variables determining the performance of the assay evaluated. Merozoites
opsonised with either malaria hyper immune IgG from Africa or IgGs raised from
vaccinations with either MSP-1, MSP-2 or AMA-1 were incubated with
PMNs/monocytes and production of ROS determined by isoluminol-amplified
chemiluminesence in triplicate assays. ELISA assays were performed alongside to
determine if total antibody titres elicited by vaccination had any association with the
magnitudes of ROS measured. Results show that monocytes (fresh or cryopreserved) and
PMNs are effective at respiratory burst induction of ROS. At equivalent cell numbers,
PMNs exhibited higher ROS production than autologous monocytes (p
OWUOR, B (2021). Development Of Antibody Dependent Respiratory Burst Assay As A Tool For Evaluating Cellular Immunity To Malaria. Afribary. Retrieved from https://track.afribary.com/works/development-of-antibody-dependent-respiratory-burst-assay-as-a-tool-for-evaluating-cellular-immunity-to-malaria
OWUOR, BOAZ "Development Of Antibody Dependent Respiratory Burst Assay As A Tool For Evaluating Cellular Immunity To Malaria" Afribary. Afribary, 07 May. 2021, https://track.afribary.com/works/development-of-antibody-dependent-respiratory-burst-assay-as-a-tool-for-evaluating-cellular-immunity-to-malaria. Accessed 30 Nov. 2024.
OWUOR, BOAZ . "Development Of Antibody Dependent Respiratory Burst Assay As A Tool For Evaluating Cellular Immunity To Malaria". Afribary, Afribary, 07 May. 2021. Web. 30 Nov. 2024. < https://track.afribary.com/works/development-of-antibody-dependent-respiratory-burst-assay-as-a-tool-for-evaluating-cellular-immunity-to-malaria >.
OWUOR, BOAZ . "Development Of Antibody Dependent Respiratory Burst Assay As A Tool For Evaluating Cellular Immunity To Malaria" Afribary (2021). Accessed November 30, 2024. https://track.afribary.com/works/development-of-antibody-dependent-respiratory-burst-assay-as-a-tool-for-evaluating-cellular-immunity-to-malaria