Controlled human malaria infection (CHMI) outcomes in Kenyan adults is associated with prior history of malaria exposure and anti-schizont antibody response
Author(s)
Type
Journal Article
Abstract
BACKGROUND: Individuals living in endemic areas acquire immunity to malaria following repeated parasite exposure. We sought to assess the controlled human malaria infection (CHMI) model as a means of studying naturally acquired immunity in Kenyan adults with varying malaria exposure. METHODS: We analysed data from 142 Kenyan adults from three locations representing distinct areas of malaria endemicity (Ahero, Kilifi North and Kilifi South) enrolled in a CHMI study with Plasmodium falciparum sporozoites NF54 strain (Sanaria® PfSPZ Challenge). To identify the in vivo outcomes that most closely reflected naturally acquired immunity, parameters based on qPCR measurements were compared with anti-schizont antibody levels and residence as proxy markers of naturally acquired immunity. RESULTS: Time to endpoint correlated more closely with anti-schizont antibodies and location of residence than other parasite parameters such as growth rate or mean parasite density. Compared to observational field-based studies in children where 0.8% of the variability in malaria outcome was observed to be explained by anti-schizont antibodies, in the CHMI model the dichotomized anti-schizont antibodies explained 17% of the variability. CONCLUSIONS: The CHMI model is highly effective in studying markers of naturally acquired immunity to malaria. Trial registration Clinicaltrials.gov number NCT02739763. Registered 15 April 2016.
Date Issued
2022-01-24
Date Acceptance
2022-01-11
Citation
BMC Infect Dis, 2022, 22 (1)
Journal / Book Title
BMC Infect Dis
Volume
22
Issue
1
Copyright Statement
© The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.
License URL
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/35073864
PII: 10.1186/s12879-022-07044-8
Subjects
Anti-schizont antibody response
Controlled human malaria infection
Malaria exposure
Plasmodium falciparum
Adult
Animals
Antibody Formation
Child
Humans
Kenya
Malaria
Malaria Vaccines
Malaria, Falciparum
Plasmodium falciparum
Schizonts
Publication Status
Published
Coverage Spatial
England
Article Number
ARTN 86