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Updated: Jun 15, 2026
08:06
Study of Phagolysosome Biogenesis in Live Macrophages
Published on: March 10, 2014
Autophagosomes can support Yersinia pseudotuberculosis replication in macrophages
Kevin Moreau1, Sandra Lacas-Gervais, Naonobu Fujita
1Cellular Microbiology of Infectious Pathogens, Center of Infection and Immunity of Lille, Institut Pasteur de Lille, Lille, France.
Cellular Microbiology
|February 26, 2010
Summary
Yersinia pseudotuberculosis infection hijacks the autophagy pathway in macrophages, preventing autophagosome acidification for bacterial replication. Inhibiting autophagy causes bacteria to enter acidic compartments, revealing a novel host-pathogen interaction mechanism.
Area of Science:
- Microbiology
- Cell Biology
- Immunology
Background:
- Yersinia pseudotuberculosis replicates within macrophages, but its intracellular trafficking and survival mechanisms are not fully understood.
- The role of host cell pathways, such as autophagy, in Yersinia infection is an area of active investigation.
Purpose of the Study:
- To investigate the intracellular trafficking of Yersinia pseudotuberculosis within macrophages.
- To determine the role of the autophagy pathway in Yersinia pseudotuberculosis replication and survival inside host cells.
Main Methods:
- In vitro infection of bone marrow-derived macrophages with Yersinia pseudotuberculosis.
- Analysis of bacterial colocalization with autophagosomes and assessment of autophagosome acidification.
- Evaluation of bacterial trafficking upon autophagy inhibition.
Main Results:
- Yersinia pseudotuberculosis activates the host cell autophagy pathway upon internalization.
- Subverted autophagosomes containing Yersinia pseudotuberculosis remain non-acidic, supporting bacterial replication.
- Inhibition of autophagy leads to Yersinia pseudotuberculosis trafficking into acidic cellular compartments.
Conclusions:
- Yersinia pseudotuberculosis actively manipulates the host autophagy pathway to facilitate its intracellular replication.
- The study elucidates a novel mechanism of Yersinia evasion from host immune responses by preventing autophagosome maturation.
- Findings provide insights into host cell signaling during intracellular Yersinia infection and potential therapeutic targets.
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