title: A novel experimental platform for toxigenic and non-toxigenic Corynebacterium ulcerans infection in mice.
abstract: Corynebacterium ulcerans is a zoonotic pathogen that can produce diphtheria toxin and causes an illness categorized as diphtheria in the European Union because its clinical appearance is similar to that of diphtheria caused by Corynebacterium diphtheriae. Despite the importance of the pathogen in public health, the organism's mechanism of infection has not been extensively studied, especially in experimental animal models. Therefore in the present study we constructed an intranasal infection system for mice. Mice are insensitive to diphtheria toxin and this has the advantage of excluding the cytotoxic effect of the toxin that might interfere with the analysis of the early stage of infection. Both the toxigenic and non-toxigenic C. ulcerans strains were capable of killing mice within 3 days after inoculation at 10(7) colony-forming units per mouse. In experimentally infected animals, C. ulcerans was detected in the respiratory tract but not in the intestinal tract. The bacterium was also detected in peripheral blood and it disseminated into the lung, kidney and spleen to produce a systemic infection. This experimental infection system provides a platform for analyzing the virulence of C. ulcerans in future studies.
authors.affiliation: Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan School of Animal Science, Nippon Veterinary and Life Science University, Tokyo, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Mochizuki
authors.affiliation: Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan School of Animal Science, Nippon Veterinary and Life Science University, Tokyo, Japan.
authors.forename: Honami
authors.initials: H
authors.lastname: Saeki
authors.affiliation: Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan miwaki@nih.go.jp.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Iwaki
authors.affiliation: Division of Biosafety Control and Research, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Hitrotaka
authors.initials: H
authors.lastname: Takagi
authors.affiliation: Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Keigo
authors.initials: K
authors.lastname: Shibayama
authors.affiliation: School of Animal Science, Nippon Veterinary and Life Science University, Tokyo, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Amao
authors.affiliation: Department of Bacteriology II, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology; D003352:Corynebacterium / Q000276:immunology / Q000472:pathogenicity*; D003354:Corynebacterium Infections / Q000175:diagnosis / Q000382:microbiology* / Q000401:mortality; D004166:Diphtheria Antitoxin / Q000097:blood; D004195:Disease Models, Animal; D005260:Female; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D051379:Mice; D009297:Nasal Mucosa / Q000382:microbiology / Q000473:pathology; D015047:Zoonoses
chemical_list: D000907:Antibodies, Bacterial; D004166:Diphtheria Antitoxin; D007074:Immunoglobulin G
keywords: Corynebacterium; animal model; diphtheria; intranasal infection; respiratory infection; zoonosis