Advanced application of bovine intestinal epithelial cell line for evaluating regulatory effect of lactobacilli against heat-killed enterotoxigenic Escherichia coli-mediated inflammation

• Published in: BMC microbiology Vol. 13; no. 1; p. 54
• Main Authors: Takanashi, Naoya, Tomosada, Yohsuke, Villena, Julio, Murata, Kozue, Takahashi, Takuya, Chiba, Eriko, Tohno, Masanori, Shimazu, Tomoyuki, Aso, Hisashi, Suda, Yoshihito, Ikegami, Shuji, Itoh, Hiroyuki, Kawai, Yasushi, Saito, Tadao, Alvarez, Susana, Kitazawa, Haruki
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 07-03-2013; BioMed Central
• Subjects: Animals; Bacteria; Cattle; Cell Line; Cytokines; Cytokines - metabolism; Enterotoxigenic Escherichia coli - immunology; Enterotoxigenic Escherichia coli - pathogenicity; Epithelial cells; Epithelial Cells - microbiology; Escherichia coli; Genetic aspects; Host-Pathogen Interactions; Inflammation; Inflammation Mediators - metabolism; Kinases; Lacticaseibacillus casei - immunology; Lactobacillus; Lactobacillus casei; Physiological aspects; Proteins; Rodents; Signal Transduction; Studies; Canada; Japan; Angola
• ISSN: 1471-2180; 1471-2180
• DOI: 10.1186/1471-2180-13-54

Previously, a bovine intestinal epithelial cell line (BIE cells) was successfully established. This work hypothesized that BIE cells are useful in vitro model system for the study of interactions of microbial- or pathogen-associated molecular patterns (MAMPs or PAMPs) with bovine intestinal epithelial cells and for the selection of immunoregulatory lactic acid bacteria (LAB).
All toll-like receptor (TLR) genes were expressed in BIE cells, being TLR4 one of the most strongly expressed. We demonstrated that heat-stable PAMPs of enterotoxigenic Escherichia coli (ETEC) significantly enhanced the production of IL-6, IL-8, IL-1α and MCP-1 in BIE cells by activating both NF-κB and MAPK pathways. We evaluated the capacity of several lactobacilli strains to modulate heat-stable ETEC PAMPs-mediated inflammatory response in BIE cells. Among these strains evaluated, Lactobacillus casei OLL2768 attenuated heat-stable ETEC PAMPs-induced pro-inflammatory response by inhibiting NF-κB and p38 signaling pathways in BIE cells. Moreover, L. casei OLL2768 negatively regulated TLR4 signaling in BIE cells by up-regulating Toll interacting protein (Tollip) and B-cell lymphoma 3-encoded protein (Bcl-3).
BIE cells are suitable for the selection of immunoregulatory LAB and for studying the mechanisms involved in the protective activity of immunobiotics against pathogen-induced inflammatory damage. In addition, we showed that L. casei OLL2768 functionally modulate the bovine intestinal epithelium by attenuating heat-stable ETEC PAMPs-induced inflammation. Therefore L. casei OLL2768 is a good candidate for in vivo studying the protective effect of LAB against intestinal inflammatory damage induced by ETEC infection or heat-stable ETEC PAMPs challenge in the bovine host.