Limits...
E. coli Nissle 1917 Affects Salmonella adhesion to porcine intestinal epithelial cells.

Schierack P, Kleta S, Tedin K, Babila JT, Oswald S, Oelschlaeger TA, Hiemann R, Paetzold S, Wieler LH - PLoS ONE (2011)

Bottom Line: Another E. coli strain expressing F1C fimbriae was also adherent to IPEC-J2 cells, and was similarly inhibitory against Salmonella invasion like EcN.We propose that EcN affects Salmonella adhesion through secretory components.This mechanism appears to be common to many E. coli strains, with strong adherence being a prerequisite for an effective reduction of SiiE-mediated Salmonella adhesion.

View Article: PubMed Central - PubMed

Affiliation: Institut für Mikrobiologie und Tierseuchen, Freie Universität Berlin, Berlin, Germany. Peter.Schierack@HS-Lausitz.de

ABSTRACT

Background: The probiotic Escherichia coli strain Nissle 1917 (EcN) has been shown to interfere in a human in vitro model with the invasion of several bacterial pathogens into epithelial cells, but the underlying molecular mechanisms are not known.

Methodology/principal findings: In this study, we investigated the inhibitory effects of EcN on Salmonella Typhimurium invasion of porcine intestinal epithelial cells, focusing on EcN effects on the various stages of Salmonella infection including intracellular and extracellular Salmonella growth rates, virulence gene regulation, and adhesion. We show that EcN affects the initial Salmonella invasion steps by modulating Salmonella virulence gene regulation and Salmonella SiiE-mediated adhesion, but not extra- and intracellular Salmonella growth. However, the inhibitory activity of EcN against Salmonella invasion always correlated with EcN adhesion capacities. EcN mutants defective in the expression of F1C fimbriae and flagellae were less adherent and less inhibitory toward Salmonella invasion. Another E. coli strain expressing F1C fimbriae was also adherent to IPEC-J2 cells, and was similarly inhibitory against Salmonella invasion like EcN.

Conclusions: We propose that EcN affects Salmonella adhesion through secretory components. This mechanism appears to be common to many E. coli strains, with strong adherence being a prerequisite for an effective reduction of SiiE-mediated Salmonella adhesion.

Show MeSH

Related in: MedlinePlus

Effects of E. coli supernatants on growth of Salmonella Typhimurium.Confluent monolayers of IPEC-J2 cells were pre- and/or co-incubated with E. coli supernatants (SN). Cells were infected with Salmonella Typhimurium using an MOI of 100∶1 Salmonella to host cells for one hour. Thereafter, numbers of extracellular, non-adherent Salmonella were determined. Growth rates are expressed as growth in percent (%) relative to Salmonella growth in cell culture medium (Salmonella mono-infection). The data are the mean ± S.E.M. of at least three separate experiments in duplicate wells. * = p<0.01 compared to Salmonella mono-infection. EcN: E. coli Nissle 1917.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3040738&req=5

pone-0014712-g005: Effects of E. coli supernatants on growth of Salmonella Typhimurium.Confluent monolayers of IPEC-J2 cells were pre- and/or co-incubated with E. coli supernatants (SN). Cells were infected with Salmonella Typhimurium using an MOI of 100∶1 Salmonella to host cells for one hour. Thereafter, numbers of extracellular, non-adherent Salmonella were determined. Growth rates are expressed as growth in percent (%) relative to Salmonella growth in cell culture medium (Salmonella mono-infection). The data are the mean ± S.E.M. of at least three separate experiments in duplicate wells. * = p<0.01 compared to Salmonella mono-infection. EcN: E. coli Nissle 1917.

Mentions: The inhibitory effect of EcN against Salmonella invasion might have been due to the inhibition of Salmonella growth by E. coli supernatants, which inevitably affects invasion efficiencies. To exclude such effects, Salmonella numbers were determined in cell culture supernatants in parallel to the invasion assays. Supernatants of all three E. coli did not, or only slightly (EcN), affect extracellular growth of Salmonella within the one hour Salmonella incubation time (Figure 5).


E. coli Nissle 1917 Affects Salmonella adhesion to porcine intestinal epithelial cells.

Schierack P, Kleta S, Tedin K, Babila JT, Oswald S, Oelschlaeger TA, Hiemann R, Paetzold S, Wieler LH - PLoS ONE (2011)

Effects of E. coli supernatants on growth of Salmonella Typhimurium.Confluent monolayers of IPEC-J2 cells were pre- and/or co-incubated with E. coli supernatants (SN). Cells were infected with Salmonella Typhimurium using an MOI of 100∶1 Salmonella to host cells for one hour. Thereafter, numbers of extracellular, non-adherent Salmonella were determined. Growth rates are expressed as growth in percent (%) relative to Salmonella growth in cell culture medium (Salmonella mono-infection). The data are the mean ± S.E.M. of at least three separate experiments in duplicate wells. * = p<0.01 compared to Salmonella mono-infection. EcN: E. coli Nissle 1917.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3040738&req=5

pone-0014712-g005: Effects of E. coli supernatants on growth of Salmonella Typhimurium.Confluent monolayers of IPEC-J2 cells were pre- and/or co-incubated with E. coli supernatants (SN). Cells were infected with Salmonella Typhimurium using an MOI of 100∶1 Salmonella to host cells for one hour. Thereafter, numbers of extracellular, non-adherent Salmonella were determined. Growth rates are expressed as growth in percent (%) relative to Salmonella growth in cell culture medium (Salmonella mono-infection). The data are the mean ± S.E.M. of at least three separate experiments in duplicate wells. * = p<0.01 compared to Salmonella mono-infection. EcN: E. coli Nissle 1917.
Mentions: The inhibitory effect of EcN against Salmonella invasion might have been due to the inhibition of Salmonella growth by E. coli supernatants, which inevitably affects invasion efficiencies. To exclude such effects, Salmonella numbers were determined in cell culture supernatants in parallel to the invasion assays. Supernatants of all three E. coli did not, or only slightly (EcN), affect extracellular growth of Salmonella within the one hour Salmonella incubation time (Figure 5).

Bottom Line: Another E. coli strain expressing F1C fimbriae was also adherent to IPEC-J2 cells, and was similarly inhibitory against Salmonella invasion like EcN.We propose that EcN affects Salmonella adhesion through secretory components.This mechanism appears to be common to many E. coli strains, with strong adherence being a prerequisite for an effective reduction of SiiE-mediated Salmonella adhesion.

View Article: PubMed Central - PubMed

Affiliation: Institut für Mikrobiologie und Tierseuchen, Freie Universität Berlin, Berlin, Germany. Peter.Schierack@HS-Lausitz.de

ABSTRACT

Background: The probiotic Escherichia coli strain Nissle 1917 (EcN) has been shown to interfere in a human in vitro model with the invasion of several bacterial pathogens into epithelial cells, but the underlying molecular mechanisms are not known.

Methodology/principal findings: In this study, we investigated the inhibitory effects of EcN on Salmonella Typhimurium invasion of porcine intestinal epithelial cells, focusing on EcN effects on the various stages of Salmonella infection including intracellular and extracellular Salmonella growth rates, virulence gene regulation, and adhesion. We show that EcN affects the initial Salmonella invasion steps by modulating Salmonella virulence gene regulation and Salmonella SiiE-mediated adhesion, but not extra- and intracellular Salmonella growth. However, the inhibitory activity of EcN against Salmonella invasion always correlated with EcN adhesion capacities. EcN mutants defective in the expression of F1C fimbriae and flagellae were less adherent and less inhibitory toward Salmonella invasion. Another E. coli strain expressing F1C fimbriae was also adherent to IPEC-J2 cells, and was similarly inhibitory against Salmonella invasion like EcN.

Conclusions: We propose that EcN affects Salmonella adhesion through secretory components. This mechanism appears to be common to many E. coli strains, with strong adherence being a prerequisite for an effective reduction of SiiE-mediated Salmonella adhesion.

Show MeSH
Related in: MedlinePlus