Development of vaccine for Clostridium difficile infection using membrane fraction of nontoxigenic Clostridium difficile.

Although standard antibiotic therapy is performed for diarrhea and pseudomembranous colitis caused by Clostridium difficile, a high recurrence rate of C. difficile infection (CDI) remains a major problem. We previously showed that a membrane fraction of nontoxigenic C. difficile (ntCDMF) was effective as a vaccine antigen by in vitro experiments. In this study, we examined whether ntCDMF had an in vivo effect in animal challenge experiments. By intrarectal immunization with ntCDMF, the number of C. difficile cells in feces of mice was decreased approximately 99% compared to the control mice. In addition, survival rate of C. difficile-challenged hamsters was increased almost 30% by immunization with ntCDMF. These results showed that ntCDMF could be a practical vaccine candidate.