Figure 1.

JAM-A^−/− mice have decreased lung zonula occludens 1 (ZO-1) expression. A: Lungs were harvested from littermate control mice (+/+) or JAM-A^−/− mice (−/−) and homogenized in a protease inhibitor cocktail, and proteins were resolved by SDS-PAGE, analyzed by immunoblot, and quantified as described in Materials and Methods. Of the tight junction proteins examined, claudin-5 (Cldn-5), Cldn-7, and ZO-1 levels were significantly different in lungs from JAM-A^−/− mice compared with those from wild-type mice. JAM-A is undetectable in JAM-A^−/− mice. B: Representative immunoblots. Data are expressed as means ± SD. n = 4. ^∗P < 0.05.