FIGURE 6.

NLRP3^−/− mice exhibit increased apoptotic alveolar epithelial cells. Lung samples were obtained from WT and NLRP3^−/− mice exposed to normoxia or hyperoxia for 72 h. A, lung sections were analyzed by TUNEL staining. Arrowheads indicate TUNEL-positive cells. B, quantitative analysis (n = 3–4). C, lung sections were immunohistochemically stained with antibody against cleaved caspase-3. Arrowheads indicate cleaved caspase-3-positive cells. D, quantitative analysis (n = 3–4). Data are expressed as the means ± S.E. **, p < 0.01.