FIG. 5.

Representative confocal scanning laser micrographs illustrating ZO-1 integrity in human duodenal epithelial monolayers. Preparations were coincubated with either 5% DMEM growth media following pretreatment with DMSO vehicle (A), G. lamblia NF sonicates for 24 h following pretreatment with DMSO vehicle (B), or G. lamblia NF strain sonicates for 24 h following pretreatment with the caspase-3 inhibitor Z-DEVD-FMK (C). Control monolayers exhibit typical continuous ZO-1 pericellular organization at the periphery of individual enterocytes. Monolayers incubated with NF strain sonicates exhibit focal disruption of ZO-1 along the pericellular junctions (arrow), and punctate ZO-1 redistribution (arrowhead) throughout the monolayer. Pretreatment with a caspase-3 inhibitor prevents the ZO-1 disruption induced by G. lamblia. Magnification, ×600.