Figure 4.

Representative histological sections from control lung (a), 7-day post-bleomycin lung (b) and 21-day post-bleomycin lung (c). The sections were chosen to highlight the common characteristics of each group— in particular, the elevated neutrophils at 7 days and elevated macrophages at 21 days. A more objective evaluation of inflammatory cell density can be seen in Table 1. Note that the alveolar structure is somewhat distorted in all of the sections because the lungs were collapsed during the NMR studies and were not reinflated for histology.