Prevention of Helicobacter pylori infection by lactobacilli in a gnotobiotic murine model.
BACKGROUND
Helicobacter pylori is a bacterium which causes gastric inflammatory diseases. Oral inoculation of H pylori usually results in only a temporary colonisation without a successful infection in the stomach of conventional mice in which lactobacilli are the predominant indigenous bacteria.


OBJECTIVE
To determine whether lactobacilli exert an inhibitory effect on colonisation by H pylori in the stomach.


METHODS
The effects of H pylori on attachment to murine and human gastric epithelial cells and the H pylori mediated release of interleukin-8 (IL-8) by these cells were examined in vitro. Lactobacillus salivarius infected gnotobiotic BALB/c mice and control germ free mice were inoculated orally with H pylori to examine whether L salivarius can inhibit colonisation by H pylori.


RESULTS
L salivarius inhibited both the attachment and IL-8 release in vitro. H pylori could not colonise the stomach of L salivarius infected gnotobiotic BALB/c mice, but colonised in large numbers and subsequently caused active gastritis in germ free mice. In addition, L salivarius given after H pylori implantation could eliminate colonisation by H pylori.


CONCLUSIONS
These findings suggest the possibility of lactobacilli being used as probiotic agents against H pylori.
Kabir
A M
AM
Department of Infectious Diseases, Tokai University, School of Medicine, Kanagawa, Japan.
Aiba
Y
Y
Takagi
A
A
Kamiya
S
S
Miwa
T
T
Koga
Y
Y
D000818:Animals; D000898:Antibiosis / Q000502:physiology*; D001422:Bacterial Adhesion / Q000502:physiology*; D004195:Disease Models, Animal; D005753:Gastric Mucosa / Q000378:metabolism / Q000382:microbiology; D005856:Germ-Free Life; D016481:Helicobacter Infections / Q000517:prevention & control*; D016480:Helicobacter pylori / Q000502:physiology*; D016209:Interleukin-8 / Q000378:metabolism; D007778:Lactobacillus / Q000502:physiology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C
D016209:Interleukin-8