Figure 5: NF-κB activation in polarized Caco-2-NF-κB-hrGFP C3 clone cells. Polarized in plastic culture plates (grey continuous line), transwell filter (grey dotted line) and nonpolarized (black line) cells were stimulated during 48 h with TNF-α (a) or IL-1β (b). For polarization in transwell filter, only TNF-α was assayed and it was added in the basolateral chamber. Cells were trypsinized and GFP expression was analyzed by flow cytometry. NF-κB activation was determined as previously described. Caco-2-NF-κB-hrGFP C3 clone cells were polarized for 21 days and then fixed, permeabilized, and stained with Texas Red-X Phalloidin (for actin distribution, red) and DAPI (for nuclei localization, blue). All images were obtained through confocal microscopy. Representative cells of basal and apical membranes are shown in left and right images, respectively (c). Data was expressed as mean of triplicates with SD error bars.