The ten nests of SPF Kunming 5-day-old suckling mice were divided into control group and experimental group，with 5 nests in each group. Each suckling mouse in control group was given 100 μL PBS per day，the mouse in experimental group was given 100 μL 1×10⁶ PFU·mL^－1 SA11 strain rotavirus.The fecal samples of suckling mice were collected，and Shigella was isolated and identified by biochemical test， serological detection and 16S rRNA sequencing.The Caco-2 cells were divided into control group and Shigella infection group. Different concentrations of Shigella were used to infect the Caco-2 cells for different time. The cell survival rates in various groups were detected by trypan blue staining， and the expression levels of Claudin-1 and Occludin mRNA and proteins in the cells in various groups were detected by Real-time PCR and Western blotting methods.

The biochemical identification of bacteria showed that the color of inclined surface of disaccharide iron medium did not change， the bottom was yellow， and the puncture line was obvious， which was suspected of pathogenic intestinal bacteria. It was negative for lactose and positive for glucose， maltose， sucrose and mannitol.The 16S rRNA sequencing results showed 99% homology with Shigella， and it was identified as Shigella. Compared with control group， there was no significant difference in the cell survival rate within 4 h of infection in Shigella group （P>0.05）； when cocultured with 1×10⁶ CFU·mL^－1 Shigella for 3 h， the expression levels of Claudin-1 and Occludin mRNA and proteins in the Caco-2 cells were decreased significantly （P<0.05）.

Shigella isolated from feces of diarrhea model mice infected with rotavirus can reduce the expression levels of Occludin and Claudin-1 in the human colon adenocarcinoma cells（Caco-2）， improve the permeability of intestinal epithelial cells， and affect the normal barrier function of intestinal epithelial cells.