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Super-resolution Imaging of Proteus mirabilis Biofilm by Expansion Microscopy
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Proteus mirabilis: The Enemy Within
Amiran Dzutsev1, Giorgio Trinchieri2
1Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA; Leidos Biomedical Research, Inc., Frederick, MD 21702, USA.
Immunity
|April 23, 2015
Abstract:
The organism needs to tailor the intestinal inflammatory response to pathogenic bacteria and to pathobionts that are only occasionally pathogenic. In this issue of Immunity, Seo et al. (2015) show that the pathobiont Proteus mirabilis induces NLRP3 inflammasome-dependent interleukin-1β (IL-1β) release from CCR2(+) Ly6C(high) inflammatory monocytes.
Insights
The gut must control inflammation against harmful bacteria. Proteus mirabilis triggers interleukin-1β release via the NLRP3 inflammasome pathway in inflammatory monocytes.
Area of Science:
- Immunology
- Microbiology
- Gastroenterology
Background:
- The host immune system must distinguish between commensal microbiota and potential pathogens.
- Intestinal inflammation is crucial for eliminating pathogenic bacteria but must be tightly regulated to prevent damage from commensals or pathobionts.
- Pathobionts, like Proteus mirabilis, can cause disease under certain conditions.
Purpose of the Study:
- To investigate the mechanism by which the pathobiont Proteus mirabilis elicits an inflammatory response in the gut.
- To identify the specific immune cells and molecular pathways involved in the host's response to P. mirabilis.
Main Methods:
- The study utilized mouse models of intestinal infection.
- Immune cell populations were analyzed using flow cytometry.
- The role of the NLRP3 inflammasome and its downstream signaling molecules, such as interleukin-1β (IL-1β), was assessed.
Main Results:
- Proteus mirabilis infection led to the activation of the NLRP3 inflammasome.
- This activation resulted in the release of IL-1β from a specific subset of inflammatory monocytes (CCR2(+) Ly6C(high)).
- The study demonstrated a direct link between P. mirabilis and inflammasome-mediated inflammation.
Conclusions:
- The NLRP3 inflammasome is a key component in the host's response to the pathobiont Proteus mirabilis.
- Inflammatory monocytes play a critical role in mediating IL-1β release during P. mirabilis infection.
- Understanding these pathways is essential for developing strategies to manage intestinal inflammatory diseases.
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