Infection and pathogenesis of a murine strain of Escherichia coli with genetically introduced Shiga toxin type I operon in conventional mice.
The pathogenic response elicited by Shiga toxin type I (Stx1)-producing Escherichia coli was studied using an E. coli strain BME5 obtained from the natural flora of the mouse and used on three different strains of mice. The recombinant strain BME5/Stx1 was prepared by introducing the gene for Stx1. Following an oral inoculation of 1.0x10(9)cfu of BME5/Stx1 faecal recovery of 1.0x10(8)cfu/g faeces over 3 weeks was obtained. Neurologic signs as well as histopathological changes of the intestine and the kidneys were observed within 3 days after infection and elevated serum cytokines including IL-1beta and TNF-alpha were observed. Furthermore, the recombinant organisms were established in the intestine and showed exquisitely virulence when infected peritoneally in mice, while parent strain BME5 though colonized did not show any pathological changes. These results suggest that E. coli BME/Stx1 can colonize the mouse intestine under natural environment, and induced systemic neural changes and inflammation in the intestine and kidneys.
Department of Oral Microbiology, Osaka University Faculty of Dentistry, Suita- Osaka, 565-0871, Japan. ichiro@dent.osaka-u.ac.jp
Ichiro
I
Nakagawa
Masanobu
M
Nakata
Taihei
T
Yamamura
Satoshi
S
Wakisaka
Shigetada
S
Kawabata
Shigeyuki
S
Hamada
D000284:Administration, Oral; D000818:Animals; D016207:Cytokines / Q000097:blood; D004195:Disease Models, Animal; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000503:physiopathology*; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D007422:Intestines / Q000382:microbiology / Q000503:physiopathology; D007668:Kidney / Q000382:microbiology / Q000503:physiopathology; D051379:Mice; D008815:Mice, Inbred Strains; D009876:Operon; D011995:Recombination, Genetic; D022622:Shiga Toxin 1 / Q000235:genetics* / Q000378:metabolism; D014774:Virulence
D016207:Cytokines; D022622:Shiga Toxin 1