title: Extraintestinal infection of Helicobacter cinaedi induced by oral administration to Balb/c mice.
abstract: Although Helicobacter cinaedi was initially considered an opportunistic pathogen in immunocompromised patients, it was later shown to also infect immunocompetent and healthy individuals. Sporadic bacteremia due to H. cinaedi has frequently been reported; however, whether the bacterium can be translocated after passage through the intestinal mucosa remains unclear. In the present study, a preclinical small animal model that faithfully reproduces H. cinaedi infection in humans was developed. Balb/c male mice were orally inoculated with a single dose of 6.8 × 107CFU of a human clinical H. cinaedi strain. The organism persistently colonized the intestinal tract of the mice, particularly the cecum and colon, for at least 56 days, and the bacteria were excreted in the feces. Although inoculated bacteria were recovered from the spleen, liver, kidney, lung, bladder and mesenteric lymph nodes during the first 2 weeks of bacteremia, the organism was not isolated from these organs after 4 weeks, suggesting that complement- and antibody-mediated serum sensitivity account for the relatively low frequency of systemic infection. However, H. cinaedi was isolated from the biceps femoris, triceps branchii, latissimus dorsi, and trapezius muscles beyond 2 weeks after infection and after production of specific anti-H. cinaedi IgM and IgG antibodies. The present findings suggest that experimental infection of Balb/c mice with H. cinaedi may be a useful model for further studies of H. cinaedi pathogenesis, prophylaxis or therapeutic interventions in vivo.
authors.affiliation: Center for Animal Disease Control, University of Miyazaki, Miyazaki, Japan.
authors.forename: Takako
authors.initials: T
authors.lastname: Taniguchi
authors.affiliation: Clinical Laboratory, University of Miyazaki Hospital, Miyazaki, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Saeki
authors.affiliation: Department of Rheumatology, Infectious Diseases and Laboratory Medicine, University of Miyazaki, Miyazaki, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Okayama
authors.affiliation: Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Hayashi
authors.affiliation: Center for Animal Disease Control, University of Miyazaki, Miyazaki, Japan.|Laboratory of Veterinary Public Health, Department of Veterinary Medical Science, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan.
authors.forename: Naoaki
authors.initials: N
authors.lastname: Misawa
mesh_terms: D000284:Administration, Oral; D000825:Animal Structures / Q000382:microbiology; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D016470:Bacteremia / Q000382:microbiology* / Q000473:pathology*; D018988:Bacterial Translocation; D001769:Blood / Q000382:microbiology; D004195:Disease Models, Animal; D005243:Feces / Q000382:microbiology; D016998:Helicobacter / Q000254:growth & development*; D016481:Helicobacter Infections / Q000382:microbiology* / Q000473:pathology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008297:Male; D008807:Mice, Inbred BALB C; D013997:Time Factors
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D007075:Immunoglobulin M
keywords: Bacteremia; Helicobacter cinaedi; colonization; persistent infection