The Effect of Lactobacillus rhamnosus on Enterohemorrhagic Escherichia coli Infection of Human Intestinal Cells In Vitro

Abstract

There are many examples of probiotic effects of various lactic bacteria on enteropathogens. In this study, Lactobacillus strains (L. rhamnosus, L. gasseri, L. casei and L. plantarum) were tested in an in vitro model of enterohemorrhagic Escherichia coli (EHEC) infection of a human colon epithelial cell line, C2BBe1. While the adhesion and colonization of EHEC was not affected by any of the lactobacillus strains tested, the internalization of EHEC into the cell line was markedly suppressed by L. rhamnosus, though not by others. Concerning the possible mechanisms, the viabilities of EHEC and host cell were not affected by the presence of L. rhamnosus. Simple competitions at certain receptors were unlikely because the suppressive effect on EHEC internalization was strictly dependent on viable L. rhamnosus and could not be observed with the conditioned medium or killed L. rhamnosus. The fact that L. rhamnosus showed outstanding potential for adhering to the colon epithelial cell line, compared with other strains, suggested that an avid interaction between L. rhamnosus and the host cell might be modulating intra-cellular events responsible for the internalization of EHEC.

Lactobacillus caseiDN-114 001 Inhibits the Ability of Adherent-InvasiveEscherichia coliIsolated from Crohn's Disease Patients To Adhere to and To Invade Intestinal Epithelial Cells

“…Several reports have confirmed the ability of probiotic Lactobacilli to inhibit the ability of pathogenic bacteria to adhere to and to invade intestinal epithelial cells (4,10,20,26,27). The inhibition levels observed with L. casei DN-114 001 are similar to or even higher than those reported for Lactobacilli on the adhesion of various pathogens (4,11,18,20,49).…”

Probiotics Reduce Enterohemorrhagic Escherichia coli O157:H7- and Enteropathogenic E. coli O127:H6-Induced Changes in Polarized T84 Epithelial Cell Monolayers by Reducing Bacterial Adhesion and Cytoskeletal Rearrangements

“…Previous work has shown, for example, that E. coli O157:H7 binds to the surfaces of S. boulardii cells (9). On the other hand, Hirano and coworkers (12) reported that L. rhamnosus blocks the internalization, but not the adherence, of E. coli O157:H7 in Caco-2 cells. Other lactic acid-producing bacteria, including Lactobacillus gasseri, Lactobacillus casei, and Lactobacillus plantarum, have no effect on either the binding or internalization of E. coli O157:H7 in Caco-2 cell monolayers (12).…”

“…On the other hand, Hirano and coworkers (12) reported that L. rhamnosus blocks the internalization, but not the adherence, of E. coli O157:H7 in Caco-2 cells. Other lactic acid-producing bacteria, including Lactobacillus gasseri, Lactobacillus casei, and Lactobacillus plantarum, have no effect on either the binding or internalization of E. coli O157:H7 in Caco-2 cell monolayers (12). This study shows that L. rhamnosus and L. acidophilus have the ability to adhere to host epithelial cells and reduce the binding of both E. coli O157:H7 and E. coli E2348/69 to host epithelial cells.…”

Probiotics and prebiotics — renaissance of a therapeutic principle

“…The findings point to the possible role of SH compounds in the protective effect of some probiotics [72]. Lactobacillus GG significantly suppresses internalization of enterohemorrhagic E. coli in tissue culture [34,73]. This effect is mediated by high adhesivity of the probiotic to colonocytes and by MUC-3 gene activation with subsequent mucus secretion [74].…”