title: The non-toxigenic Clostridium difficile CD37 protects mice against infection with a BI/NAP1/027 type of C. difficile strain.
abstract: Clostridium difficile CD37, a clinical isolate from the USA, does not produce toxin A, B or binary toxin. The aim of this study was to determine whether strain CD37 can protect mice against infection from a challenge with a toxigenic C. difficile strain. Three groups of mice (n = 10) were pretreated with a antibiotics cocktail for 5 days, switched to sterile water for 2 days, and given one dose of clindamycin (10 mg/kg) one day (day-1) before challenge (day 0) with a toxigenic C. difficile strain. Group 1 (CD37 + UK6) was given 10(7)C. difficile CD37 vegetative cells by gavage twice a day on days -1 and -2, followed by challenge with 10(6) spores of the toxigenic C. difficile UK6 (BI/NAPI/027) on day 0; Group 2 (UK6) was infected with 10(6)C. difficile UK6 spores on day 0; Group 3 (CD37) was challenged with 10(6) CD37 vegetative cells on day 0. Our data show that pre-inoculation of strain CD37 provided mice significant protection (survival, p < 0.001 between groups CD37 + UK6 and UK6) against subsequent infection with the strain UK6, while mice infected with CD37 only did not develop any symptoms of C. difficile infection (CDI). Our results highlight the potential use of CD37 as a therapeutic strain for the prevention of primary and recurrent CDI in humans.
authors.affiliation: Tufts University, Department of Infectious Diseases and Global Health, USA; State Key Laboratory of Veterinary Etiological Biology, National Foot and Mouth Disease Reference Laboratory, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, 730046, China.
authors.forename: Keshan
authors.initials: K
authors.lastname: Zhang
authors.affiliation: Tufts University, Department of Infectious Diseases and Global Health, USA; Department of Gastroenterology, Jiangsu Province Hospital of TCM, China.
authors.forename: Song
authors.initials: S
authors.lastname: Zhao
authors.affiliation: Tufts University, Department of Infectious Diseases and Global Health, USA.
authors.forename: Yuankai
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Gastroenterology, Jiangsu Province Hospital of TCM, China.
authors.forename: Xuejun
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Department of Gastroenterology, Jiangsu Province Hospital of TCM, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Shen
authors.affiliation: Department of Gastroenterology, Jiangsu Province Hospital of TCM, China.
authors.forename: Yugen
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Tufts University, Department of Infectious Diseases and Global Health, USA; Department of Molecular Medicine, University of South Florida, USA. Electronic address: sun5@health.usf.edu.
authors.forename: Xingmin
authors.initials: X
authors.lastname: Sun
mesh_terms: D000818:Animals; D000898:Antibiosis; D001427:Bacterial Toxins / Q000096:biosynthesis; D016360:Clostridioides difficile / Q000145:classification / Q000235:genetics / Q000502:physiology*; D004761:Enterocolitis, Pseudomembranous / Q000382:microbiology* / Q000517:prevention & control; D005260:Female; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL
chemical_list: D001427:Bacterial Toxins