Fig. 1

Alveolar collapse and lung infiltration by PMN cells in silica-instilled mice. Representative photomicrographs of lungs from control (Ctrl) or silica-instilled (Si) animals. A Ctrl 24 h; B Si 24 h; C Ctrl 15 d; D Si 15 d. E Percentage of collapsed alveoli in Ctrl (white bars) or Si (black bars) animals. F Cellularity expressed as total cell counts per area. Data are expressed as mean ± SEM; white bars represent Ctrl mice, and black bars represent silica-instilled (Si) mice. Two-way ANOVA with Duncan post hoc test. *p < 0.05 between Ctrl and Si; ^#p < 0.05 between 24 h and 15 d. N = 7–10 mice per experimental group