FIG. 3.

Activation of NF-κB and p38 MAP kinase is required for bladder epithelial cytokine responses to E. coli. (a through d) Immunohistochemical staining (in red) for the p65 subunit of NF-κB is shown in the upper panels, and differential interference microscopy is shown in the lower panels. (a) NF-κB in unstimulated T24 cells is localized to the cytoplasm. (b) After stimulation with type 1 piliated E. coli, NF-κB is translocated to the nuclei of T24 cells. AAEC185/pUT2002 (FimH⁻) also induces nuclear localization (data not shown). (c) Preincubation of T24 cells with MG-132 inhibits nuclear localization of NF-κB in response to E. coli. (d) Preincubation with the p38 MAP kinase inhibitor SB203580 does not inhibit NF-κB translocation. (e and f) T24 and 5637 cell responses to FimH⁺ or FimH⁻ E. coli (solid bars) are blocked by preincubation with MG-132 (open bars) or SB203580 (shaded bars).