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06:51
Cefoperazone-treated Mouse Model of Clinically-relevant Clostridium difficile Strain R20291
Published on: December 10, 2016
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A human gut ecosystem protects against C. difficile disease by targeting TcdA
Sarah Lynn Martz1, Mabel Guzman-Rodriguez1, Shu-Mei He1
1Division of Infectious Diseases/GI Diseases Research Unit Wing, Department of Medicine, Kingston General Hospital, Queen's University, 76 Stuart Street, Kingston, ON, K7L 2V7, Canada.
Journal of Gastroenterology
|June 23, 2016
Summary
A defined microbial ecosystem therapeutic (MET-1) cures recurrent C. difficile infection by neutralizing C. difficile toxins and reducing inflammation. MET-1 enhances host barrier function and degrades toxins, rather than affecting bacterial viability.
Area of Science:
- Microbiology
- Gastroenterology
- Immunology
Background:
- Recurrent Clostridioides difficile infection (rCDI) is a significant clinical challenge.
- A defined microbial ecosystem therapeutic (MET-1) derived from healthy donor feces can cure rCDI.
- The protective mechanisms of MET-1 against rCDI are not fully understood.
Purpose of the Study:
- To investigate the mechanisms by which MET-1 confers protection against C. difficile infection.
- To determine if MET-1 neutralizes C. difficile toxins and reduces host inflammation.
Main Methods:
- Utilized in vivo models: antibiotic-associated C. difficile colitis and murine ileal loop.
- Employed in vitro assays: FITC-phalloidin staining, F-actin Western blots, apoptosis assays in Caco2 cells, and transepithelial electrical resistance in T84 cells.
Main Results:
- MET-1 significantly reduced local and systemic inflammation in a C. difficile infection model.
- MET-1 decreased C. difficile toxin A (TcdA) cytotoxicity and levels in stool, without impacting bacterial viability.
- MET-1 protected host cells from TcdA-induced damage by preserving cytoskeletal integrity and barrier function.
Conclusions:
- MET-1 protects against C. difficile infection by neutralizing toxins and reducing inflammation.
- MET-1 enhances host barrier function and degrades TcdA, contributing to its therapeutic efficacy.
- MET-1's protective effects are primarily mediated by toxin neutralization, not by direct impact on C. difficile viability.
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