Proteome-wide antigenic profiling in Ugandan cohorts identifies associations between age, exposure intensity, and responses to repeat-containing antigens in Plasmodium falciparum
- University of California, San Francisco, United States
- Chan Zuckerberg Initiative, United States
- University of California, Berkeley, United States
- Infectious Diseases Research Collaboration, Uganda
- London School of Hygiene and Tropical Medicine, United Kingdom
Abstract
Protection against Plasmodium falciparum, which is primarily antibody-mediated, requires recurrent exposure to develop. The study of both naturally acquired limited immunity and vaccine induced protection against malaria remains critical for ongoing eradication efforts. Towards this goal, we deployed a customized P. falciparum PhIP-seq T7 phage display library containing 238,068 tiled 62-amino acid peptides, covering all known coding regions, including antigenic variants, to systematically profile antibody targets in 198 Ugandan children and adults from high and moderate transmission settings. Repeat elements - short amino acid sequences repeated within a protein - were significantly enriched in antibody targets. While breadth of responses to repeat-containing peptides was twofold higher in children living in the high versus moderate exposure setting, no such differences were observed for peptides without repeats, suggesting that antibody responses to repeat-containing regions may be more exposure dependent and/or less durable in children than responses to regions without repeats. Additionally, short motifs associated with seroreactivity were extensively shared among hundreds of antigens, potentially representing cross-reactive epitopes. PfEMP1 shared motifs with the greatest number of other antigens, partly driven by the diversity of PfEMP1 sequences. These data suggest that the large number of repeat elements and potential cross-reactive epitopes found within antigenic regions of P. falciparum could contribute to the inefficient nature of malaria immunity.
Data availability
All data generated or analyzed during this study are included in the manuscript, supporting files and in the Dryad repository with the doi:doi.org/10.7272/Q69S1P9G
Article and author information
Author details
Isabel Rodriguez-Barraquer
Funding
Chan Zuckerberg Biohub
- Joseph L DeRisi
Chan Zuckerberg Biohub (Investigator program)
- Bryan Greenhouse
National Institutes of Health (A1089674 (East Africa ICEMR))
- Bryan Greenhouse
National Institutes of Health (AI119019)
- Bryan Greenhouse
National Institutes of Health (AI144048)
- Bryan Greenhouse
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The study protocol was reviewed and approved by the Makerere University School of Medicine Research and Ethics Committee (Identification numbers 2011-149 and 2011-167), the London School of Hygiene and Tropical Medicine Ethics Committee (Identification numbers 5943 and 5944), the University of California, San Francisco, Committee on Human Research (Identification numbers 11-05539 and 11-05995) and the Uganda National Council for Science and Technology (Identification numbers HS-978 and HS-1019). Written informed consent was obtained from all participants in the study. For children, this was obtained from the parents or guardians. The US control samples were from New York Blood Center and these samples came from volunteer blood donors who consented as follows, "I authorize NYBC to use or transfer my blood or portions of it for any purpose it deems appropriate, including transfusion, research, or commercial purposes."
Copyright
© 2023, Raghavan 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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Proteome-wide antigenic profiling in Ugandan cohorts identifies associations between age, exposure intensity, and responses to repeat-containing antigens in Plasmodium falciparum
eLife 12:e81401.
https://doi.org/10.7554/eLife.81401
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