title: Detection of Escherichia coli enterotoxins by using mouse adrenal cell and suckling mouse assays: collaborative study.
abstract: The ability of 10 Escherichia coli strains to produce heat-stable enterotoxin (ST) and heat-labile enterotoxin (LT) was determined by 8 analysts in a collaborative study. The suckling mouse model and the mouse adrenal cell line (Y-1) tests were used to detect ST and LT, respectively. Cultures for assay were grown 24 h in casamino acid-yeast extract-trace salts broth at 37 degrees C in a shaker incubator at 250 rpm. Cell-free culture broth prepared by centrifugation and filtration was divided into 2 portions: One was heated for 30 min and used both for ST assay and as a heated control for LT assay; the other was used unheated for LT assay. Results were expressed as positive for ST, positive for LT, positive for ST and LT, or negative for both ST and LT; percent of correct estimates was calculated for each culture for each analyst. At the 95% confidence interval, the overall correct results were 96.3 +/- 2.9 and 95.0 +/- 3.4% for ST and LT, respectively. The test performances thus were satisfactory for detecting ST and LT produced in vitro by E. coli. The method has been adopted official first action.
mesh_terms: D000311:Adrenal Glands / Q000166:cytology*; D000818:Animals; D000833:Animals, Suckling; D001681:Biological Assay; D002478:Cells, Cultured; D002772:Cholera Toxin / Q000633:toxicity; D003470:Culture Media; D004768:Enterotoxins / Q000633:toxicity*; D004926:Escherichia coli / Q000032:analysis*; D051379:Mice
chemical_list: D003470:Culture Media; D004768:Enterotoxins; D002772:Cholera Toxin