FIG 8.
Structural and functional injuries at the tight junction caused by Afa/Dr DAEC in enterocyte-like cells. The drawing on the left summarizes the observed cellular events. The secreted and internalized Sat toxin induces the reorganization of the TJ-associated proteins ZO-1 and occludin without affecting E-cadherin expression (1). Sat induces an increase in transcellular and paracellular passages (2). (A) Low- and high-magnification micrographs show the immunofluorescence labeling of structural TJ-associated ZO-1 protein observed by CLMS in control and AAEC185psat-infected cells. Note the Sat-induced disappearance of the protein from the cell-to-cell contacts. (Reprinted from reference 137 with permission.) (B) Fluid domes observed by phase-contrast CLSM in control and AAEC185psat-infected cells. Note the Sat-induced increase of the fluid dome height and surface.