title: Campylobacter jejuni colonization of mice with limited enteric flora.
abstract: We have developed experimental murine Campylobacter infection models which demonstrate efficient establishment and reproducible, high-level colonization. Following oral inoculation, wild-type C3H mice with normal enteric flora were colonized inconsistently and inefficiently by C. jejuni strain 81-176. However, C3H mice with a limited gut flora (LF) were efficiently colonized at high levels (10(8) CFU/g of stool or large intestine tissue) followed by clearance after several weeks. Large intestine tissue showed minimal to mild inflammation at days 7 and 28 postinoculation. In striking contrast, C3H SCID mice with the same limited flora remained persistently colonized at a consistently high level until they were euthanized 8 months postinoculation. Lower gastrointestinal tract tissue from LF-SCID mice showed marked to severe inflammation in the colon and cecum at days 7 and 28 and intense inflammation of the stomach at day 28. These findings indicate that although the innate response alone cannot block colonization persistence, it is sufficient to orchestrate marked gut inflammation. Moreover, the adaptive immune response is critical to mediate C. jejuni clearance from the colonized gut. To validate our LF murine model, we verified that motility and chemotaxis are critical for colonization. Insertion-deletion mutations were generated in motB and fliI, which encode products essential for motility and flagellar assembly, and in the presumptive chemotaxis gene cheA (histidine kinase). All mutants failed to establish colonization in LF mice. Our limited flora murine colonization models serve as tractable, reproducible tools to define host responses to C. jejuni infection and to identify and characterize virulence determinants required for colonization.
authors.affiliation: Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, 10833 Le Conte Ave., CHS 43-326, Los Angeles, CA 90095-1747, USA. gichang@ucla.edu
authors.forename: Christopher
authors.initials: C
authors.lastname: Chang
authors.forename: Jeff F
authors.initials: JF
authors.lastname: Miller
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D002169:Campylobacter Infections / Q000276:immunology / Q000382:microbiology*; D016123:Campylobacter jejuni / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D002633:Chemotaxis / Q000235:genetics; D004195:Disease Models, Animal; D041981:Gastrointestinal Tract / Q000382:microbiology* / Q000473:pathology; D007420:Intestine, Large / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D008565:Membrane Proteins / Q000235:genetics; D000072236:Methyl-Accepting Chemotaxis Proteins; D051379:Mice / Q000276:immunology / Q000382:microbiology*; D008809:Mice, Inbred C3H; D006180:Proton-Translocating ATPases / Q000235:genetics; D017384:Sequence Deletion; D013270:Stomach / Q000382:microbiology / Q000473:pathology
chemical_list: D001426:Bacterial Proteins; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins; C064779:MotB protein, Bacteria; C069251:fliI protein, bacteria; D006180:Proton-Translocating ATPases