Figure 4.

Distribution of HMGB1, MCP1 and RAGE in the lungs after acute exacerbation. The cells immunoreactive for HMGB1 (a) and MCP-1 (b) in the consecutive sections of the autopsied lung tissues of IPF patients who died after acute exacerbation (bars = 100 μm). The intense immunoreactivity of RAGE, the receptor of HMGB1, was observed in type I alveolar epithelial cells in these lungs ((c) and (d)) ((c), bar = 100 μm; (d), bar = 10 μm). The sections were counterstained with Elastica-Goldner staining, showing the elastic fibers in purple and collagen in light blue ((a)–(d)).