Mouse duodenum as a model of inflammation induced by enterotoxigenic Escherichia coli K88

Introduction: The aim of the experiment was to establish the enterotoxigenic Escherichia coli K88 (ETEC K88)-induced BALB/c mouse duodenum inflammation model. Material and Methods: Mice were administered different concentrations of E. coli K88 (1.0 × 10⁷-10⁹ CFU/mL) for 3 d by means of an esophageal catheter. Results: The results showed that the treated group expressed several significant clinical symptoms, such as reduced dietary demands and weight loss, an increased presence of IL-1α, TNF-α, and MPO in the peripheral blood, and some pathological changes in the duodenum. On the 6^th-8^th days, the body weight of the mice was the lowest. On the 8^th day, there were significant differences in IL-1α, TNF-α, and MPO levels compared to the control group (P < 0.05), the gap between the duodenum mucous layer and the muscular layer had widened, the number of goblet cells was increased, and the inflammatory infiltrate and inflammation changes in the lamina propria and the mucous layer were the most obvious. Conclusion: The duodenum inflammation was the most severe on day 8; thus, the model was successfully established. In addition, varying concentrations of ETEC K88 did not significantly influence the duodenum inflammation (P > 0.05).