Coordination of humoral immune factors dictates compatibility between Schistosoma mansoni and Biomphalaria glabrata
Abstract
Immune factors in snails of the genus Biomphalaria are critical for combating Schistosoma mansoni, the predominant cause of human intestinal schistosomiasis. Independently, many of these factors play an important role in, but do not fully define, the compatibility between the model snail B. glabrata, and S. mansoni. Here, we demonstrate association between four previously characterized humoral immune molecules; BgFREP3, BgTEP1, BgFREP2 and Biomphalysin. We also identify unique immune determinants in the plasma of S. mansoni-resistant B. glabrata that associate with the incompatible phenotype. These factors coordinate to initiate haemocyte-mediated destruction of S. mansoni sporocysts via production of reactive oxygen species. The inclusion of BgFREP2 in a BgFREP3-initiated complex that also includes BgTEP1 almost completely explains resistance to S. mansoni in this model. Our study unifies many independent lines of investigation to provide a more comprehensive understanding of the snail immune system in the context of infection by this important human parasite.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
Natural Sciences and Engineering Research Council of Canada (2018-05209)
- Patrick Hanington
Natural Sciences and Engineering Research Council of Canada (2018- 522661)
- Patrick Hanington
National Natural Science Foundation of China (31272682)
- Xinzhong Wu
Guangxi 16 Natural Science Foundation (2016JJD130059)
- Xinzhong Wu
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All animal work observed ethical requirements and was approved by the Canadian Council of Animal Care and Use Committee (Biosciences) for the University of Alberta (AUP00000057).
Reviewing Editor
- Bruno Lemaître, École Polytechnique Fédérale de Lausanne, Switzerland
Publication history
- Received: September 7, 2019
- Accepted: January 7, 2020
- Accepted Manuscript published: January 9, 2020 (version 1)
- Version of Record published: January 20, 2020 (version 2)
Copyright
© 2020, Li 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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