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Morphology of intestinal colonization of Yersinia enterocolitica serovar O3 in mice
K Kaneko1, K Uehara, H Hayashidani
1Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Japan.
Abstract:
The present study was made to know the morphology of the initial invasion and lesions involved in the intestinal colonization of Yersinia enterocolitica serovar O3 in the epithelium of Peyer's patches of mice. Microfold (M) cells formed a specific structure like a pseudopodium and the bacteria were observed on the surface of the pseudopodium-like structure 4 hr after oral administration of serovar O3. The colonies of serovar O3 were observed in the epithelium and the lamina propria of the Peyer's patches dome region, and the bacteria grown in the Peyer's patches were in direct contact with the lumen without covered with the host tissue 24 hr after the administration.
Insights
Yersinia enterocolitica serovar O3 invades mouse Peyer's patches by forming pseudopodia on microfold cells. Bacteria colonize the epithelium and lamina propria, remaining in direct lumenal contact without host tissue covering.
Area of Science:
- Microbiology
- Immunology
- Gastroenterology
Background:
- Yersinia enterocolitica is a significant foodborne pathogen.
- Intestinal colonization involves interactions with Peyer's patches.
- The initial invasion mechanisms remain incompletely understood.
Purpose of the Study:
- To elucidate the morphology of initial Yersinia enterocolitica serovar O3 invasion.
- To characterize the lesions formed during intestinal colonization.
- To investigate bacterial interaction with Peyer's patch epithelium in mice.
Main Methods:
- Oral administration of Yersinia enterocolitica serovar O3 to mice.
- Microscopic examination of Peyer's patches at 4 and 24 hours post-administration.
- Observation of bacterial interaction with microfold (M) cells and epithelial layers.
Main Results:
- Microfold (M) cells formed pseudopodium-like structures for bacterial attachment.
- Yersinia enterocolitica serovar O3 was observed on M cell pseudopodia within 4 hours.
- Bacterial colonies were found in the epithelium and lamina propria, maintaining lumenal contact at 24 hours.
Conclusions:
- Yersinia enterocolitica serovar O3 utilizes M cell pseudopodia for initial intestinal invasion.
- The pathogen establishes colonization within Peyer's patches, remaining exposed to the intestinal lumen.
- This direct lumenal contact may facilitate pathogen survival and dissemination.
