Mycobacterium avium infection through the alimentary tract in mice.
Intestinal infection by Mycobacterium avium was investigated in C57BL/6 and BALB/c mouse strains. Single intragastric administration of a massive dose (10(8] or multiple administration of a lower dose (10(7), 10 times) established infection principally in the mesenteric lymph-node (MLN); a continuous or intermittent fecal excretion of the bacilli was detected by 6-8 weeks after the administration. Based on three criteria--isolation of the organisms from the MLN and from feces, and detection of acid-fast bacilli in sections of the MLN--germ-free (GF) BALB/c mice exhibited clearer dose-effect relations than the flora-bearing (FB) counterparts. After intragastric administration, the organisms were probably trapped in the Peyer's patch and then transferred to the MLN at an early period (by 4-7 days), persistent infection thus being established in the MLN. Systemic involvement evolved both in athymic and euthymic mice after a prolonged period of time (more than 40 weeks) showing far more severe involvement in the former regardless of the presence of floral organisms.
Ueda
K
K
Yamazaki
S
S
Yamamoto
S
S
D000818:Animals; D005260:Female; D007422:Intestines / Q000382:microbiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009162:Mycobacterium avium / Q000472:pathogenicity; D012376:Rodent Diseases / Q000382:microbiology*; D014385:Tuberculosis, Gastrointestinal / Q000382:microbiology / Q000662:veterinary*; D014388:Tuberculosis, Lymph Node / Q000382:microbiology / Q000662:veterinary