Figure legends
Fig. 1 Changes in the weights of the mice in each group. The data are presented as the means ± SD of 3 mice per group.
Fig. 2 Changes in C. rodentium levels in faecal pellets. The data are presented as the means ± SD of 3 mice per group.
Fig. 3 DAI assessment showing a lower value in the TS+CR group than that observed in the TS group. The data are presented as the means ± SD of 3 mice per group.
Fig. 4 Histopathological analysis of the colons of mice. Colon samples were excised, fixed in 4% paraformaldehyde and embedded in paraffin. Sections were stained with H&E for light microscopy assessments of epithelial damage (original magnification, 100×).
A, Mice were treated with PBS as control, the structure of the colon villus was integrated, and the gland was clearly visible.
B, In mice from the CR group, intestinal epithelial cells were necrotic and shedding, intestinal villi were shortened and fused, and the crypts were extended. In addition, a large number of lymphocytes, neutrophils, and eosinophils had infiltrated into the mucosa and submucosa.
C, In mice from the TS group, a high number of goblet cells were detected, but there was no obvious pathological damage.
D, Hyperplasia of colonic epithelial tissue in the TS+CR mice disappeared, the lesions were limited to the mucosa, and the lamina propria of the mucosa was scattered with inflammatory cells.
Fig. 5 Changes in the IgG1 and IgG2a contents of serum post C. rodentium infection. The data are presented as the means ± SD of 3 mice per group. *P < 0.05, **P < 0.01, ***P < 0.001.
Fig. 6 Demonstration of the gating strategy for the flow cytometry analysis of mouse CD4+CD25+Foxp3+Tregs and Th cells from spleens and MLNs 7 (A) and 14 days (B) after administration of C. rodentium . In this experiment single-cell suspensions were prepared from the spleens and MLNs of mice in each group and stained following surface and intracellular staining protocols. The data were collected with a FACSDiva flow cytometer and analysed. Lymphocytes were identified by their scatter properties (FSC-A x SSC-A plot).
Fig. 7 The number of Th cells in the spleens and MLNs of mice from the four groups at 7 and 14 days. Analysis of CD4+CD25+Foxp3+Tregs in the spleens and MLNs of mice from each group. The number of CD4+CD25+Foxp3+Tregs in mice from the TS+CR group increased compared with that observed in the CR group. The data are presented as the means ± SD of 3 mice per group. *P < 0.05, **P < 0.01, ***P < 0.001.