FIG. 4.

Cell viability is unaffected by EAEC strain 042 infection but is significantly decreased after JM221 infection. Polarized T84 monolayers were infected for 3 h as described in legend to Fig. 1; at 24 h postinfection, cells were stained using the Live/Dead cell viability assay as described in Materials and Methods, and the number of dead (red) cells was enumerated by epifluorescence microscopy. Dead cells were counted in 20 fields at ×63 magnification from each well. Statistical significance was determined from a one-way ANOVA with Tukey's posttest. *, significant difference from HS and uninfected control (P < 0.05).