Figure 7.

LPS can induce apoptosis in AMs of silicosis subjects. (A) AMs in the observer group were treated without or with LPS (100, 150, 200 μg/ml), and cell apoptosis determined after 24 h using TUNEL. Scale bar: 30 μm. (B) Quantification of TUNEL-positive apoptotic cells in AMs treated with different LPS concentrations. Six fields per sample were analyzed for each cell population. The bar graph shows the percentage of TUNEL-positive nuclei relative to DAPI-positive total nuclei (n = 5 each group. ^*, P < 0.05 vs. CON; ^#, P < 0.05 vs. 100 μg/ml LPS group). (C) Representative photographs of TUNEL staining in AMs at different stages of silicosis. Scale bar: 30 μm. (D) Quantification of TUNEL-positive apoptotic cells in AMs at different stages of silicosis. n = 5 for observer, stage I, II and III groups. ^*, P < 0.05 vs. observer group; ^#, P < 0.05 vs. stage I patient group).