Figure 3.

Decreased severity of asbestos-induced inflammation and mucin in OPN^−/− mice. OPN^+/+ and OPN^−/− mice were exposed to chrysotile asbestos (8 mg/m³ per day) for 9 days. Lung tissue sections were stained with H&E or Alcian Blue-PAS and were scored for inflammation or mucin production, respectively. A: Severity of inflammation scored by assessing influx of macrophages and polymorphonuclear cells in H&E-stained tissue sections from asbestos-exposed mice. No detectable inflammation was observed in any air-exposed animals. B: A representative histological section of mucin staining with Alcian Blue-PAS for each treatment group. Arrowheads indicate examples of positive staining (pinkish-purple). C: Percentage of bronchioles affected with mucin in Alcian Blue-PAS stained tissue sections from asbestos-exposed mice. No detectable mucin was observed in any air-exposed animals. *P ≤ 0.05, asbestos versus air exposure; **P ≤ 0.05, asbestos-exposed OPN^+/+ versus OPN^−/−.