Additional file 1: Figure S1. of Proteases and oxidant stress control organic dust induction of inflammatory gene expression in lung epithelial cells

Effects of protease inhibitors on IL-8 protein levels. A549 (A) and Beas2B (B–D) cells were treated with medium (C), 0.25 % dust extract (DE) or dust extract combined with 25 μg/ml α1-antitrypsin (α1-AT), soybean trypsin inhibitor (SBTI), 20 μM leupeptin, 5 μM aprotinin or 10 μM E64 for 3 h. IL-8 protein levels in cell medium and cell lysates were determined by ELISA. IL-8 protein levels in cell lysates were normalized to total protein content. IL-8 protein levels in dust extract treated medium or lysate were arbitrarily considered as 100 and relative levels in treated cells are shown. Data are shown as means ± SE (n = 3) for A549 cell lysate (A), means ± SD (n = 2) for Beas2B cell lysate and Beas2B medium (B and C), and means ± SE (n = 3) for Beas2B medium (D). (TIF 1520 kb)