Lactobacillus plantarum Reduces the In Vitro Secretory Response of Intestinal Epithelial Cells to Enteropathogenic Escherichia coli Infection

Abstract

OBJECTIVE: Enteropathogenic (EPEC) is a Gram-negative bacillus that causes diarrhea. Secretory responses of intestinal epithelial cells can be seen after EPEC infection. Probiotics, which are live bacteria that have proven benefit to the host, play a role in the treatment and prevention of the different enteric pathogens. The goals of the study were to determine whether the probiotic agent (LBP) strain 299v alters the secretory changes seen in EPEC infection and, if so, what underlying mechanism is possible. METHODS: Caco-2 cell monolayers were rapidly infected with EPEC strain E2348/69 and immediately mounted in Ussing chambers. The monolayers were exposed to LBP before, after, and simultaneously with EPEC infection. Short circuit current (Isc) was measured in the Ussing chamber. RESULTS: EPEC infection caused an increase in short circuit current that was reduced by preincubation with LBP ( < 0.01). No direct bactericidal effect was observed, but LBP reduced the attachment of EPEC to Caco-2 cells. CONCLUSION: LBP can play an important role in reducing the secretory change in response to EPEC infection, possibly through inhibition of its binding. However, the presence of the probiotic agent before the infection is necessary. In this setting, its role is more preventive rather than therapeutic.