CASP3 and infection: EPEC was able to induce the cleavage of procapase-3 from 2 h of infection, and the cleaved caspase-3 band increased as a function of infection time, while the ΔespC mutant was unable to induce efficient cleavage of procaspase-3 given that the detection of the cleaved caspase-3 band was very faint.