The use of a porcine intestinal cell model system for evaluating the food safety risk of
The use of porcine intestinal cell lines in assessing toxicity of Bacillus cereus probiotics in conjunction with animal challenge trials with toxigenic B. cereus was investigated. Toxigenic and toxin deletion mutants of B. cereus and two probiotic strains (Paciflor and Toyocerin) were examined for bacterial attachment, cytotoxicity and ability to induce nitric oxide as markers of toxicity. Both cytotoxicity and production of nitric oxide were detected in wild‐type toxigenic strains and the Paciflor probiotic strain but not Toyocerin. Attachment of B. cereus was low (less than 1%) in all strains. Discrimination between toxigenic B. cereus and the probiotic strains was possible semi‐quantitatively via dilution. Despite cytotoxicity in vitro, challenge experiments using 108–109 spores of the toxigenic B. cereus NVH75/95 in weaned piglets did not induce diarrhoea or intestinal lesions. Thus, the pig small intestinal epithelial intestinal cell line PSI is appropriate for identification of potential toxicity in B. cereus strains and sets a low threshold for risk of enterotoxicity to humans.
Document Type: Research Article
Affiliations: 1: Department of Microbiology, Biochemistry, Molecular Biology and Biotechnology, Faculty of Agriculture and Life Sciences, University of Maribor, Hoce 2: Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, Denmark 3: Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, Oslo
Publication date: December 1, 2011