Fig. 4
Caco2 cell invasion analysis by plate counting and flow cytometry. A Experiments were performed in duplicate and repeated three times. Statistical analyses of the invasive capacity compared to wild-type (WT) were performed using the SPSS 13.0 for Windows software; a p < 0.05 was considered to be significant, marked with * and p < 0.01 was considered to be extremely significant, marked with **; B Negative control is the same volume of bacterial suspension without simultaneous staining treatment by SYTO 9, and the value of 103 was chosen as the cut-off for cell invasion because 100% unstained bacteria were covered. Red cycle: the percentage of live invasion bacteria cells labelled by SYTO 9 fluorescence at above 103