FIG. 1.

Disappearance of F-actin stress fibers and F-actin accumulation in ruffles in DAEC C1845-infected preconfluent cultured human embryonic intestinal INT407 cells. After bacterial adhesion (3 h at 37°C) and three washes to remove the nonadhering bacteria, the cells were fixed, permeabilized with Triton X-100, and stained with FITC-phalloidin to show F-actin filaments. (A) F-actin distribution in control cells showing well-ordered F-actin stress fibers and regular margins of cells. (B) Disappearance of F-actin stress fibers and induction of F-actin ruffles at the margins of DAEC C1845-infected cells. (C) Adhesion of DAEC C1845 in the same cells (B) observed by phase-contrast microscopy.