Lactobacillus delbrueckii subsp lactis CIDCA 133 modulates response of human epithelial and dendritic cells infected with Bacillus cereus.

ROLNY, I. S.; TISCORNIA, I; RACEDO, S. M.; PÉREZ, P. F. AND BOLLATI-FOGOLÍN, M.

Beneficial Microbes

Wageningen Academic Publishers

Año: 2016 vol. 7 p. 749 - 760

1876-2883

Several studies demonstrate that fermented dairy products containing probiotic microorganisms promote human health. In the present work we focus on the effect of a potentially probiotic lactobacillus strain (Lactobacillus delbrueckii subsp. lactis CIDCA 133) in an in vitro model of Bacillus cereus infection. Our results showed that infection of HT-29 cells by B. cereus induces signaling through NF-κB pathway and that the presence of strain CIDCA 133 increases stimulation. In contrast, B. cereus-induced IL-8 production is partially abrogated by strain CIDCA 133 thus suggesting multiple signaling pathways. Epithelial (HT-29 cells) and monocyte-derived dendritic cells (DC) were used in co-culture. After infection of HT-29 cells (upper compartment), B. cereus B10502 was found in the lower compartment interacting with dendritic cells (DC) although this interaction was diminished in the presence of strain CIDCA 133. Expression of HLA-DR and CD86 was induced in DC by infection B. cereus of HT-29 cells in the upper compartment and no further effect was observed in the presence of strain CIDCA 133. Analysis of supernatants of the lower compartment (DC) of co-cultures revealed the ability of strain CIDCA 133 to increase the production of TNF-α triggered by B. cereus B10502 whereas no effect on the producton of IL-8 and IL-6 were found. The present work demonstrates for the first time the effect of a potentially probiotic strain (Lactobacillus delbrueckii subsp. lactis CIDCA 133) in an in vitro model of B. cereus infection. Furthermore the relevance of the cellular cross?talk both in the pathogenesis of B. cereus and in the possible effect of potentially probiotic strains is emphasized.