title: Role of Shiga-like toxin I in bacterial enteritis: comparison between isogenic Escherichia coli strains induced in rabbits.
abstract: OBJECTIVE
  Enteroadherent Escherichia coli that produce Shiga-like toxins are important causes of human disease, including enterohemorrhagic E. coli-induced colitis (EHEC). The role of Shiga-like toxins in these illnesses is unclear. The aim of this study was to establish an animal model for human EHEC and to determine the role of Shiga-like toxin I (SLT-I) in this model.
  
  
  METHODS
  E. coli strain RDEC-1 is an enteroadherent rabbit diarrheal pathogen. An isogenic variant of RDEC-1 (termed RDEC-H19A) producing high levels of SLT-I was obtained by infecting RDEC-1 with an SLT-I-converting bacteriophage. The effects of in vivo enteric infection produced in rabbits by RDEC-H19A were compared with those in uninfected and RDEC-1-infected animals.
  
  
  RESULTS
  SLT-I-producing RDEC-H19A induced a severe, noninvasive, enteroadherent infection in rabbits. Clinically, infection with RDEC-H19A was more severe than infection with RDEC-1 and caused more serious histological lesions including vascular changes, edema, and more severe inflammation. Interleukin 1 and platelet-activating factor appear to be important inflammatory mediators to this infection.
  
  
  CONCLUSIONS
  The illness induced by RDEC-H19A in rabbits resembled enterohemorrhagic E. coli-induced colitis of humans. SLT-I is an important virulence factor in the pathogenesis of EHEC.
authors.affiliation: Division of Medicine, Walter Reed Army Institute of Research, Washington, D.C.
authors.forename: R
authors.initials: R
authors.lastname: Sjogren
authors.forename: R
authors.initials: R
authors.lastname: Neill
authors.forename: D
authors.initials: D
authors.lastname: Rachmilewitz
authors.forename: D
authors.initials: D
authors.lastname: Fritz
authors.forename: J
authors.initials: J
authors.lastname: Newland
authors.forename: D
authors.initials: D
authors.lastname: Sharpnack
authors.forename: C
authors.initials: C
authors.lastname: Colleton
authors.forename: J
authors.initials: J
authors.lastname: Fondacaro
authors.forename: P
authors.initials: P
authors.lastname: Gemski
authors.forename: E
authors.initials: E
authors.lastname: Boedeker
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000633:toxicity*; D004751:Enteritis / Q000209:etiology; D004760:Enterocolitis / Q000209:etiology* / Q000473:pathology; D004768:Enterotoxins / Q000633:toxicity*; D004926:Escherichia coli / Q000472:pathogenicity*; D006367:HeLa Cells; D006801:Humans; D007375:Interleukin-1 / Q000502:physiology; D008297:Male; D010972:Platelet Activating Factor / Q000502:physiology; D011817:Rabbits; D022622:Shiga Toxin 1
chemical_list: D001427:Bacterial Toxins; D004768:Enterotoxins; D007375:Interleukin-1; D010972:Platelet Activating Factor; D022622:Shiga Toxin 1