FIG 6 .
EspT, EspM2, and SopE inhibit EspH-induced caspase-3 activation. Caspase-3 activation of HeLa cells transfected with Myc-GFP or Myc-tagged bacterial RhoGEFs, uninfected or infected with EPEC with ΔespH complemented with EspH (ΔespH/pEspH) for 1 h, followed by incubation with 200 µg/ml gentamicin for 3 h, was quantified. One hundred transfected cells were counted in triplicate. Ectopic expression of Myc-tagged EspT, EspM2, or SopE78-240 markedly reduced caspase-3 activation in cells infected with ΔespH/pEspH EPEC but not Myc-tagged GFP or Map. Results are means plus SD of three independent experiments. Statistical significance is based on a Student’s t test compared to the Myc-GFP control. *, P < 0.05; **, P < 0.01.