Figure 2.

Uptake and effect of antisense (A19) oligonucleotide in MCF-10A and CACO-2 cells. MCF-10A (a and b) and CACO-2 cells (c–j) were cultured on glass coverslips. The cells were continuously grown in either random (a, c, e, g, i) or A19 (b, d, f, h, j) oligonucleotides. In some cases, the cells were fixed (PFA), permeabilized, and processed with a biotinylated sense oligonucleotide (complementary of A19, a–d; or complementary of random, e and f) followed by Texas red–conjugated streptavidin. Other monolayers were processed for indirect immunofluorescence with anti-CK19 mAb (RCK108; g–j). Some samples were observed under laser confocal microscopy as a series of confocal optical sections in the z axis (perpendicular to the plane of the monolayer), and then the transmonolayer section image was obtained as a three-dimensional reconstruction of 4 voxel thick volumes (g and h). Black arrowheads point to the apical CK19 network, and white arrowheads show the position of the basal domain. Other samples are shown desuper under standard epifluorescence microscopy (i and j). Bars: (a–f, i, j) 10 μm; (g and h) 20 μm.