FIGURE 5.

Claudin-5 induction by IL-25 is mediated by PKCϵ. A–C, MBEC4 cells were treated with IL-25 (50 ng/ml) for 24 h following pretreatment with graded doses of Gö6976 (A), bisindolylmaleimide I (Gö6850) (B), and PKCϵ inhibitor peptide (C). Claudin-5 expression in whole cell lysates was analyzed by Western blotting. D, MBEC4 cells were pretreated with PKCϵ inhibitor peptide (200 μm) and then stimulated with TNF-α (50 ng/ml) and IL-25 (50 ng/ml) or IL-25 alone for 24 h. EBA was then loaded onto the luminal side of the insert for 1 h, and the levels of EBA on the abluminal side were analyzed. Data are represented as the means ± S.E. *, p < 0.05; n = 4.