Inhibitory effect of probiotic Escherichia coli strain Nissle 1917 on adhesion to and invasion of intestinal epithelial cells by adherent-invasive E. coli strains isolated from patients with Crohn's disease.
BACKGROUND
Pathogenic adherent-invasive Escherichia coli have been isolated from ileal lesions of Crohn's disease.


OBJECTIVE
: To investigate the non-pathogenic E. coli strain Nissle 1917 (Mutaflor) as possible maintenance therapy in inflammatory bowel disease by testing its ability to prevent adherent-invasive E. coli strains from adhering to and invading human intestinal epithelial cells in vitro.


METHODS
Bacterial adhesion to and invasion of intestinal epithelial cells (Intestine-407) were assessed by counting the colony-forming units. The inhibitory effect of E. coli Nissle 1917 was determined after co-incubation with adherent-invasive E. coli strains or after pre-incubation of the intestinal epithelial cells with this probiotic strain prior to infection with adherent-invasive E. coli strains.


RESULTS
Strain Nissle 1917 exhibited dose- and time-dependent adherence to intestinal epithelial cells and inhibited the adhesion and invasion of various adherent-invasive E. coli strains. In co-infection experiments, the inhibitory effect on adherent-invasive E. coli adhesion reached 78-99.9%. Pre-incubation of intestinal epithelial cells with strain Nissle 1917 reduced adherent-invasive E. coli adhesion by 97.2-99.9%. The inhibitory effect on adherent-invasive E. coli invasion paralleled that on adhesion.


CONCLUSIONS
As strong and significant inhibitory effects on adherent-invasive E. coli adhesion and invasion were observed in co-infection and pre-infection experiments, E. coli Nissle 1917 could be efficient for preventive or curative probiotic therapy in patients with Crohn's disease.
Boudeau
J
J
Pathogénie Bactérienne Intestinale, Laboratoire de Bactériologie, Université d'Auvergne, Clermont-Ferrand, France.
Glasser
A-L
AL
Julien
S
S
Colombel
J-F
JF
Darfeuille-Michaud
A
A
D001422:Bacterial Adhesion / Q000502:physiology*; D002478:Cells, Cultured; D003424:Crohn Disease / Q000473:pathology / Q000628:therapy*; D004847:Epithelial Cells; D004926:Escherichia coli / Q000502:physiology*; D006801:Humans; D019936:Probiotics / Q000627:therapeutic use*