title: Colonization and infection of athymic and euthymic germfree mice by Campylobacter jejuni and Campylobacter fetus subsp. fetus.
abstract: Human clinical strains of Campylobacter jejuni and Campylobacter fetus subsp. fetus colonized the gastrointestinal tracts of both athymic (nu/nu) and euthymic (+/nu) germfree mice (BALB/c). Viable Campylobacter spp. (10(9) to 10(10) CFU/g [dry weight] of cecum and colon contents) were isolated on day 3 after oral challenge, and similar large numbers of viable cells were evident at several intervals during a 10-month experiment. The stomachs and upper small intestines of nu/nu and +/nu mice that were monoassociated for 224 days with C. jejuni 45100 contained 3 to 4 logs fewer viable bacteria than did their ceca or colons. Athymic mice that were monoassociated for 224 days with C. fetus subsp. fetus had 2 to 3 logs more viable Campylobacter spp. in their upper gastrointestinal tracts than did their +/nu littermates. Large viable populations (approximately 10(9)/g of contents) of C. fetus subsp. fetus were in the ceca and colons of both nu/nu and +/nu mice. All C. jejuni strains used in this study chronically infected the mesenteric lymph nodes of both nu/nu and +/nu mice. C. jejuni strains 24 and INN 73-83, which were cytotoxic for Chinese hamster ovary cells in vitro, were also more frequently isolated from the livers, spleens, and kidneys of nu/nu mice than was the weak cytotoxin-producing strain 45100. Additionally, heat-labile-enterotoxin-producing C. jejuni INN 73-83 was recovered more frequently from the internal organs of monoassociated +/nu mice than were any other Campylobacter spp. tested. Natural gastrointestinal colonization of neonatal nu/nu and +/nu mice (born to Campylobacter-colonized mothers) with Campylobacter spp. appeared to be delayed until approximately 1 to 2 weeks after birth. Conventionalization of C. jejuni 45100-monoassociated BALB/c mice with a complex mouse fecal microflora eliminated viable C. jejuni from the mesenteric lymph nodes by day 14 and from the cecum by day 78. These findings show that the gnotobiotic BALB/c mouse is a new model for studying acute and chronic host-Campylobacter sp. interactions.
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002169:Campylobacter Infections / Q000209:etiology / Q000382:microbiology*; D002168:Campylobacter fetus / Q000472:pathogenicity*; D004064:Digestive System / Q000382:microbiology; D005856:Germ-Free Life; D006801:Humans; D008198:Lymph Nodes / Q000382:microbiology; D008206:Lymphatic Diseases / Q000209:etiology; D008643:Mesentery / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D008855:Microscopy, Electron, Scanning; D008871:Microvilli / Q000382:microbiology