Occurrence of foamy macrophages during the innate response of zebrafish to trypanosome infections
- Wageningen University and Research, Netherlands
- University of Sheffield,, United Kingdom
- LIPH, CNRS, INSERM, Univ Montpellier, France
- LIPH, CNRS, INSERM, Univ Montpellier, Montpellier, France;, France
- Wageningen University & Research, Netherlands
Abstract
A tightly regulated innate immune response to trypanosome infections is critical to strike a balance between parasite control and inflammation-associated pathology. In this study, we make use of the recently established Trypanosoma carassii infection model in larval zebrafish to study the early response of macrophages and neutrophils to trypanosome infections in vivo. We consistently identified high- and low-infected individuals and were able to simultaneously characterize their differential innate response. Not only did macrophage and neutrophil number and distribution differ between the two groups, but also macrophage morphology and activation state. Exclusive to high-infected zebrafish, was the occurrence of foamy macrophages characterized by a strong pro-inflammatory profile and potentially associated with an exacerbated immune response as well as susceptibility to the infection. To our knowledge this is the first report of the occurrence of foamy macrophages during an extracellular trypanosome infection.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 2, 4, 5, 6
Article and author information
Author details
Funding
Marie Curie Initial Training Network (PITN-GA-2011-289209)
- Eva Dóró
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (022.004.005)
- Sem H Jacobs
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 animals were handled in accordance with good animal practice as defined by the European Union guidelines for handling of laboratory animals http://ec.europa.eu/environment/ chemicals/lab_animals/home_en.htm). Allanimal work at Wageningen University was approved by the local experimental animal committee (DEC number 2014095).
Copyright
© 2021, Jacobs 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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Occurrence of foamy macrophages during the innate response of zebrafish to trypanosome infections
eLife 10:e64520.
https://doi.org/10.7554/eLife.64520
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