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Mycobacterium tuberculosis Extracellular Vesicle Enrichment through Size Exclusion Chromatography
Published on: May 19, 2022
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Exosomes function in antigen presentation during an in vivo Mycobacterium tuberculosis infection
Victoria L Smith1, Yong Cheng1, Barry R Bryant1
1Department of Biological Sciences, Eck Institute for Global Health, University of Notre Dame, Notre Dame, Indiana 46556, USA.
Scientific Reports
|March 7, 2017
Summary
Mycobacterium tuberculosis infection triggers exosomes that significantly boost T cell responses. These exosomes act as crucial extracellular antigens, driving immunity during bacterial infections.
Area of Science:
- Immunology
- Microbiology
- Cell Biology
Background:
- Mycobacterium tuberculosis infection elicits a strong T cell response, yet antigen presentation by infected macrophages and dendritic cells is limited.
- Alternative antigen presentation pathways, including exosomes, are hypothesized but lack in vivo validation.
Purpose of the Study:
- To investigate the role of exosomes in T cell activation during Mycobacterium tuberculosis infection.
- To determine if exosomes serve as a significant source of extracellular antigen in vivo.
Main Methods:
- Utilized Rab27a-deficient mice, which exhibit reduced exosome trafficking of mycobacterial components.
- Employed Mycobacterium tuberculosis strains engineered to control protein trafficking to exosomes.
Main Results:
- Exosomes released during mouse Mycobacterium tuberculosis infection were found to significantly contribute to the T cell response.
- The study demonstrated that exosome-mediated antigen presentation is a key driver of T cell immunity.
Conclusions:
- Exosomes play a critical role in promoting T cell immunity during bacterial infections.
- Exosomes are an important source of extracellular antigens that activate T cells in vivo.
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