Fig. 3

SiNPs impaired lysosomal degradative capacity. a The EGFR degradation in BEAS-2b cells treated with 50 μg/mL of SiNPs for 12 h was detected by Western blot. Quantification shown at right illustrates the relative EGFR/ACTB expression level compared to 0 h. b BEAS-2b cells were treated as indicated in (a), then were fixed and immunostained with anti-EGFR antibody. Scale bars: 10 μm. c BEAS-2b cells transiently expressing CFP-LC3 and YFP-LAMP1 were either starved or exposed to SiNPs at 50 μg/mL for 12 h, then the cells were fixed and imaged by confocal microscopy. The graph at right shows a statistical assay of the colocalization coefficients of LC3-CFP and LAMP1-YFP. Scale bars: 10 μm. Data are presented as mean ± SEM, **p < 0.01, NS no significance