Myeloid-derived suppressor cells control microbial sepsis
Marc Derive1, Youcef Bouazza, Corentine Alauzet
1Groupe Choc, contrat Avenir INSERM, Faculté de Médecine, Nancy Université, Nancy, France.
Intensive Care Medicine
|May 4, 2012
Summary
Myeloid-derived suppressor cells (MDSCs) accumulate during sepsis and protect against infection by suppressing inflammation and enhancing bacterial clearance. Further research into MDSC-promoting agents may offer new sepsis treatments.
Area of Science:
- Immunology
- Microbiology
- Pathophysiology
Background:
- Myeloid-derived suppressor cells (MDSCs) are immune cells known to regulate immune responses.
- MDSCs expand during cancer, inflammation, and infection, but their role in microbial infections like sepsis is not well understood.
Purpose of the Study:
- To investigate the function and impact of MDSCs in a mouse model of sepsis.
Main Methods:
- Sepsis was induced in mice via cecal ligation and puncture.
- MDSCs were isolated from spleens at different time points post-infection.
- The function of MDSCs, including their ability to suppress T cells and their response to LPS, was analyzed.
- Adoptive transfer of MDSCs was performed in septic mice.
Main Results:
- Sepsis led to increased MDSC accumulation in spleens.
- MDSCs isolated later during infection (day 10) were more responsive to LPS and exhibited potent T cell suppression.
- Adoptive transfer of day 10 MDSCs reduced inflammation, improved bacterial clearance, and increased survival rates in septic mice.
Conclusions:
- MDSCs play a protective role during sepsis by modulating immune responses and improving outcomes.
- Pharmacological strategies aimed at expanding MDSCs warrant further investigation for sepsis treatment.
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