Expression of NF-κB in polarized and non-polarized RPE cells.

<p>A: In controls without TNF-α, immunohistochemistry shows that NF-κB p65 is expressed mainly in the cytosol of polarized RPE cells, while it is seen in both the cytosol and nucleus in non-polarized RPE cells. After TNF-α exposure, NF-κB p65 is expressed almost exclusively in the nucleus of polarized RPE cells, but NF-κB p65 is expressed mainly in the nucleus of non-polarized RPE cells. B: In Western blot analysis, a faint phospho-NF-κB p65 band can be seen in the polarized RPE cells without exposure of TNF-α, but it increases significantly after exposure to TNF-α. In contrast, phospho- NF-κB p65 is detected in non-polarized RPE cells without TNF-α, and it is increased after exposure to TNF-α. C: Semi-quantification of these band adjusted by control band of tubulin. The expression of phospho-NF-κB p65 in non-polarized RPE is greater than that in polarized RPE (<i>P</i><0.01). Although TNF-α increased the phospho-NF-κB p65 by 1.5 times in non-polarized RPE cells (<i>P</i><0.01), it was increased by more than 3 times in polarized RPE cells (<i>P</i><0.01). *; <i>P</i><0.05, **; <i>P</i><0.01, post hoc Tukey-Kramer test. Original magnifications, x200.