Related Experiment Video
Updated: Apr 30, 2026
12:50
Measuring Bacterial Load and Immune Responses in Mice Infected with Listeria monocytogenes
Published on: August 9, 2011
31.6K
Internalization assays for Listeria monocytogenes
Andreas Kühbacher1, Pascale Cossart, Javier Pizarro-Cerdá
1Unité des Interactions Bactéries Cellules, Institut Pasteur, 25 rue du Docteur Roux, Paris, 75724, France.
Methods in Molecular Biology (Clifton, N.J.)
|May 6, 2014
Summary
This study details two methods for measuring Listeria monocytogenes invasion into host cells. These assays, including the gentamicin protection assay and immunofluorescence microscopy, help quantify bacterial internalization.
Area of Science:
- Microbiology and Immunology
- Cell Biology
- Bacterial Pathogenesis
Background:
- Listeria monocytogenes is a well-established intracellular pathogen.
- Understanding host cell invasion mechanisms is crucial for studying bacterial pathogenesis.
- Quantifying bacterial internalization is essential for evaluating infection dynamics.
Purpose of the Study:
- To describe and compare two distinct assays for quantifying host cell invasion by Listeria monocytogenes.
- To provide detailed protocols for both the gentamicin protection assay and immunofluorescence-based methods.
- To enable researchers to select appropriate methods for their specific research needs.
Main Methods:
- Classical gentamicin protection assay: involves lysing infected cells and quantifying viable intracellular bacteria via colony-forming units (CFUs).
- Immunofluorescence microscopy-based assays: allow for medium- to high-throughput assessment of bacterial internalization.
- Combination of assays: utilizing both methods for a comprehensive analysis of invasion.
Main Results:
- Both the gentamicin protection assay and immunofluorescence methods effectively quantify Listeria monocytogenes invasion.
- Immunofluorescence offers advantages for medium- to high-throughput screening.
- The choice of assay depends on experimental scale and specific research questions.
Conclusions:
- Accurate quantification of Listeria monocytogenes internalization is achievable through established microbiological techniques.
- Researchers can select between CFU-based or microscopy-based assays, or combine them, for robust invasion studies.
- These methods support further investigation into host-pathogen interactions and the development of therapeutic strategies.
