COLONIZATION OF THE MOUSE UPPER GASTROINTESTINAL TRACT BY Lactobacillus murinus: A HISTOLOGICAL, IMMUNOCYTOCHEMICAL AND ULTRASTRUCTURAL STUDY

ALMIRÓN M.; TRAGLIA G.; RUBIO A.; SANJUAN N.

CURRENT MICROBIOLOGY

SPRINGER

Lugar: Berlin; Año: 2013 vol. 67 p. 395 - 398

0343-8651

Lactobacillus is normally present in animals and humans colonizing several epithelia, mainly those belonging to the upper gastrointestinal tract. Most of the information about the distribution of Lactobacillus in mice has been obtained by bacterial culture and characterization, and only few reports have described the direct presence of these bacteria in tissues, especially in the gastric mucosa. In this work, we have characterized and evaluated the location and detailed relationship between Lactobacillus and epithelia using a combination of histological, molecular, immunocytochemical and ultrastructural methods. Normal Balb/c mice were sacrificed in order to study esophagus and stomach. Partial 16S rRNA gene sequencing, Gram, and P.A.Schiff staining allowed us to demonstrate that Lactobacillus murinus isolated from each animal colonize not only the epithelium of the forestomach but also that belonging to the distal esophagus. The pattern of colonization was linear over the keratinized epithelium, and also in a vertical way of focal bacterial aggregates. This was confirmed by transmission electron microscopy, and the nature of bacteria was further assessed by immunocytochemistry. Our results indicate that Lactobacillus murinus can colonize the stomach and the esophagus epithelia in a biofilm-like manner, possibly acting as a defence barrier against colonization by other bacteria.