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Colon Ascendens Stent Peritonitis (CASP) - a Standardized Model for Polymicrobial Abdominal Sepsis
Published on: December 18, 2010
The complement system facilitates clearance of Enterococcus faecium during murine peritonitis.
Masja Leendertse1, Rob J L Willems, Roelof Flierman
1Center for Infection and Immunity Amsterdam, Academic Medical Center, Amsterdam. The Netherlands. m.leendertse@amc.uva.nl
The Journal of Infectious Diseases
|January 13, 2010
Summary
Complement deficiency severely impairs the body's ability to clear multidrug-resistant Enterococcus faecium infections. This study highlights complement's crucial role in fighting enterococcal peritonitis and subsequent systemic spread.
Area of Science:
- Immunology
- Microbiology
Background:
- Multidrug-resistant enterococci infections pose a significant global health threat.
- Host defense mechanisms against enterococcal diseases are not well understood.
- Complement proteins are known to be crucial for neutrophil-mediated phagocytosis in vitro.
Purpose of the Study:
- To investigate the role of complement in an in vivo model of Enterococcus faecium peritonitis.
- To determine the impact of complement deficiency on the host's ability to clear E. faecium infections.
Main Methods:
- In vitro analysis of phagocytosis and killing of E. faecium by neutrophils and macrophages incubated with normal or decomplemented plasma.
- Induction of E. faecium peritonitis in complement-deficient mice (CVF-treated and C3 knockout) and comparison with control groups.
- Monitoring infection progression in various tissues and organs up to 48 hours post-infection.
Main Results:
- Complement opsonization significantly enhanced E. faecium phagocytosis by immune cells.
- Complement-deficient mice showed impaired clearance of E. faecium from peritoneal fluid, blood, lungs, and liver.
- Decomplemented mice exhibited elevated peritoneal cytokine and chemokine levels without changes in cell kinetics.
Conclusions:
- Complement deficiency critically hinders the clearance of E. faecium peritonitis.
- Complement plays a vital role in host defense against systemic E. faecium infections.
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