Dynamics of macrophage polarization support Salmonella persistence in a whole living organism
- LPHI, CNRS, Université de Montpellier, France
- The Barcelona Institute of Science and Technology, Spain
- Université Paris-Saclay, CEA, CNRS, France
- Université de Montpellier, CNRS, INSERM, France
- Université de Montpellier, CNRS, INSERM, Montpellier France, France
- LIPH, CNRS, INSERM, Univ Montpellier, France
Abstract
Numerous intracellular bacterial pathogens interfere with macrophage function, including macrophage polarization, to establish a niche and persist. However, the spatiotemporal dynamics of macrophage polarization during infection within host remain to be investigated. Here, we implement a model of persistent Salmonella Typhimurium infection in zebrafish, which allows visualization of polarized macrophages and bacteria in real time at high-resolution. While macrophages polarize toward M1-like phenotype to control early infection, during later stages, Salmonella persists inside non-inflammatory clustered macrophages. Transcriptomic profiling of macrophages showed a highly dynamic signature during infection characterized by a switch from pro-inflammatory to anti-inflammatory/pro-regenerative status and revealed a shift in adhesion program. In agreement with this specific adhesion signature, macrophage trajectory tracking identifies motionless macrophages as a permissive niche for persistent Salmonella. Our results demonstrate that zebrafish model provides a unique platform to explore, in a whole organism, the versatile nature of macrophage functional programs during bacterial acute and persistent infections.
Data availability
The raw sequencing data is available in the NCBI GEO database under accession number: GSE224985, https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE224985.Figure 7 - Source Data 1 contains the numerical data used to generate the figures.Other data that support the findings are openly available from the public repository Zenodo at https://zenodo.org/records/10409519, at the publication date.
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Dynamic changes of macrophage polarization during Salmonella infection in zebrafishNCBI Gene Expression Omnibus, GSE224985.
Article and author information
Author details
Pablo Loza-Alvarez
Funding
Horizon 2020 Framework Programme (MSCA-ITN ImageInLife Grant Agreement n{degree sign} 721537)
- Pablo Loza-Alvarez
- Georges Lutfalla
Horizon 2020 Framework Programme (MSCA-ITN Inflanet Grant Agreement n{degree sign} 955576)
- Mai E Nguyen-Chi
Agence Nationale de la Recherche (ANR-19-CE15-0005-01,MacrophageDynamics)
- Mai E Nguyen-Chi
Region Occitanie (REPERE « INFLANET »)
- Mai E Nguyen-Chi
Spanish Ministerio de Economía y Competitividad (CEX2019-000910-S)
- Matteo Bernardello
- Emilio Gualda emilio.jose.gualda@upc.edu.
- Pablo Loza-Alvarez
MINECO/FEDER (RYC-2015-17935)
- Matteo Bernardello
- Emilio Gualda emilio.jose.gualda@upc.edu.
- Pablo Loza-Alvarez
Horizon 2020 Framework Programme (Laserlab-Europe GA no. 871124)
- Pablo Loza-Alvarez
Fundació Privada Cellex
- Matteo Bernardello
- Emilio Gualda emilio.jose.gualda@upc.edu.
- Pablo Loza-Alvarez
Fundación Mig-Puig
- Matteo Bernardello
- Emilio Gualda emilio.jose.gualda@upc.edu.
- Pablo Loza-Alvarez
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Animal experimentation procedures were carried out according to the European Union guidelines for handling of laboratory animals (https://ec.europa.eu/environment/chemicals/lab_animals/index_en.htm) and were approved by the Comité d'Ethique pour l'Expérimentation Animale under reference CEEA-LR- B4-172-37 and APAFIS #36309-2022040114222432 V2. Fish husbandry, embryo collection, animal experimentations, handling, and euthanasia were performed at the University of Montpellier, LPHI/CNRS UMR5295, by authorized staff. All experimentations were performed under tricain (Ethyl 3-aminobenzoate) anesthesia, and every effort was made to minimize suffering. Euthanasia was performed using an anesthetic overdose of tricain.
Copyright
© 2024, Leiba 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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Dynamics of macrophage polarization support Salmonella persistence in a whole living organism
eLife 13:e89828.
https://doi.org/10.7554/eLife.89828
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