Fig. 1. Relative messenger RNA expression levels of apoptosis-associated speck-like protein (ASC) (A , C ) in human epithelial cells and alveolar macrophages and NLRP3 (B ) in alveolar macrophages. Epithelial cells and alveolar macrophages were obtained from brush and lung lavage samples, respectively, at baseline and after 5 h of mechanical ventilation (MV). Gene expression was normalized to the house-keeping gene hypoxanthine-guanine phosphoribosyl transferase (HPRT). Samples were included for analysis when paired measurement of both time points was possible. Data represent mean (SD) of n = 23 pairs for ASC in epithelial cells, n = 29 pairs for NLRP3 in alveolar macrophages, and n = 34 pairs for ASC in alveolar macrophages. *P < 0.05, **P < 0.01.