Fig. 4

LPS-induced autophagic cell death is related to RAGE activation. A Ager mRNA in WT and Ager^−/− mice lungs. B Serum levels of IL-6 and IL-8 in WT and Ager^−/− mice. C Levels of IL-6 and IL-8 in BALF of WT and Ager^−/− mice. IL-6 and IL-8 were determined by commercial ELISA kits (n = 7). D The immunoblot of RAGE in the lung sections of WT and Ager^−/− mice (n ≥ 3 examinations). E Immunochemistry of LC3 II/I expression in lung sections. Images × 40 magnification, scale bar 50 μm. F Mice lung sections were processed for transmission electron microscopy to observe the autophagic body. Red arrows indicate the number and location of autophagosomes. The scale bar for original images is 1 µm; the scale bar for enlarged images is 500 nm. G HE staining of lung sections from WT mice or Ager^−/− mice under LPS stimulation. The apoptosis of lung cells was evaluated by the TUNEL assay and images were obtained by spinning disk confocal microscopy at × 40 magnification (scale bar 50 μm) and × 200 magnification (scale bar 10 μm). P-values by Kruskal–Wallis test with Dunn’s post hoc tests. * indicates the significant difference compared with WT-CON group, # indicates the significant difference compared with WT-LPS group