Plasmodium falciparum adapts its investment into replication versus transmission according to the host environment
Abstract
The malaria parasite life cycle includes asexual replication in human blood, with a proportion of parasites differentiating to gametocytes required for transmission to mosquitoes. Commitment to differentiate into gametocytes, which is marked by activation of the parasite transcription factor ap2-g, is known to be influenced by host factors but a comprehensive model remains uncertain. Here we analyze data from 828 children in Kilifi, Kenya with severe, uncomplicated, and asymptomatic malaria infection over 18 years of falling malaria transmission. We examine markers of host immunity and metabolism, and markers of parasite growth and transmission investment. We find that inflammatory responses associated with reduced plasma lysophosphatidylcholine levels are associated with markers of increased investment in parasite sexual reproduction (i.e., transmission investment) and reduced growth (i.e., asexual replication). This association becomes stronger with falling transmission and suggests that parasites can rapidly respond to the within-host environment, which in turn is subject to changing transmission.
Data availability
Raw data and script for all the analyses in this manuscript are available at https://doi.org/10.7910/DVN/BXXVRY. mzML mass spectrometry files are available at MetaboLights at https://www.ebi.ac.uk/metabolights/editor/study/MTBLS5130
Article and author information
Author details
Funding
Wellcome Trust (110166)
- Fiona Achcar
- Lauriane Sollelis
- João Luiz Silva-Filho
- Matthias Marti
Wellcome Trust (104111)
- Fiona Achcar
- Lauriane Sollelis
- João Luiz Silva-Filho
- Matthias Marti
Royal Society (Wolfson Merit Award)
- Matthias Marti
European Research Council
- Teun Bousema
Wellcome Trust (209289/Z/17/Z)
- Abdirahman I Abdi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Ethical approval was granted by the Scientific Ethics Review Unit of the Kenya Medical Research Institute under the protocol; KEMRI/SERU/3149, and informed consent was obtained from the parents/guardian of the children.
Reviewing Editor
- Urszula Krzych, Walter Reed Army Institute of Research, United States
Publication history
- Received: November 24, 2022
- Accepted: March 1, 2023
- Accepted Manuscript published: March 14, 2023 (version 1)
Copyright
© 2023, Abdi et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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