Macrophage infection models for Mycobacterium tuberculosis

Area of Science:

• Microbiology
• Immunology
• Cell Biology

Background:

• Mycobacterium tuberculosis (M.tb) infects and resides within host macrophages.
• Understanding M.tb intracellular survival is crucial for developing effective tuberculosis treatments.
• In vitro macrophage models are essential tools for studying host-pathogen interactions.

Purpose of the Study:

• To describe standardized methods for infecting primary murine bone marrow-derived macrophages and macrophage cell lines (J774, THP-1) with M.tb.
• To outline techniques for assessing M.tb intracellular survival and growth within macrophages.
• To present protocols for preparing infected macrophages for imaging studies.

Main Methods:

• Propagation and infection of primary murine bone marrow-derived macrophages.
• Infection of J774 and THP-1 macrophage-like cell lines with M.tb.
• Characterization of M.tb intracellular survival using quantitative methods.
• Preparation of infected macrophages for microscopic analysis and imaging.

Main Results:

• Established protocols for reproducible in vitro infection of macrophages with M.tb.
• Demonstrated methods for quantifying M.tb burden within infected macrophages over time.
• Provided techniques for visualizing M.tb localization and interaction within the macrophage environment.

Conclusions:

• The described in vitro macrophage infection models provide a robust platform for studying M.tb pathogenesis.
• These methods facilitate the investigation of bacterial adaptation and survival strategies within the macrophage.
• The protocols support research aimed at identifying novel therapeutic targets for tuberculosis.