Figure 3

HPS4-YC infection induced disruption of TJ in STEC. STEC were infected with HPS4-YC for 6, 12, 18, and 24 h. A Protein levels of ZO-1 and occludin were analyzed by Western blot. The protein band intensities were quantified by ImageJ software. HPS4-YC caused a time-dependent decrease in tight junction protein levels in STEC. CT, the control group. B mRNA levels of ZO-1 and occludin were analyzed with qRT-PCR. The results are shown as the mean ± SD of triplicate independent experiments. Significant differences were analyzed using the Student t test. *, P < 0.05; **, P < 0.01; ***P < 0.001. C Immunofluorescence staining of ZO-1 and occludin in STEC. The infection times of HPS4-YC were 12 h and 24 h, then cells were fixed and the nucleus and TJ were stained (blue and green, respectively). HPS4-YC destroyed the integrity of TJ. Scale bar, 100 μm.