Advanced application of bovine intestinal epithelial cell line for evaluating regulatory effect of lactobacilli against heat-killed enterotoxigenic Escherichia coli-mediated inflammation
- Equal contributors
1 Food and Feed Immunology Group, Laboratory of Animal Products Chemistry, Graduate School of Agricultural Science, Tohoku University, Sendai, Aoba-ku, 981-8555, Japan
2 Laboratory of Clinical and Experimental Biochemistry, Reference Centre for Lactobacilli (CERELA-CONICET), Tucuman, Argentina
3 National Agriculture and Food Research Organization, National Institute of Livestock and Grassland Science, Nasushiobara, 329-2793, Japan
4 Laboratory of Animal Breading and Genetics, Graduate School of Agricultural Science, Tohoku University, Sendai, 981-8555, Japan
5 Cell Biology Laboratory, Graduate School of Agricultural Science, Tohoku University, Sendai, Aoba-ku, 981-8555, Japan
6 Department of Food, Agriculture and Environment, Miyagi University, Sendai, 982-0215, Japan
7 Division of Research and Development, Food Science Institute, Meiji Dairies Co, Kanagawa, Odawara, 250-0862, Japan
BMC Microbiology 2013, 13:54 doi:10.1186/1471-2180-13-54Published: 7 March 2013
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.