Fig. 8
Mmp12 protein expression in lung tissue. All examples illustrate findings after 90-day nanoparticle exposure. A Mmp12 positive macrophages (arrows) in lung tissue overview (×10) and B detailed view (×40) after clean air exposure, C Mmp12 positive macrophages (arrows) and AEII cells (arrowhead) in lung tissue overview (×10) and D detailed view (×40) after 3.0 mg/m3 CeO2 exposure, and E Mmp12 positive macrophages (arrows) and AEII cells (arrowhead) in lung tissue overview (×10) and F detailed view (×40) after 50.0 mg/m3 BaSO4 exposure. The images show Mmp12-positive cells counterstained with hematoxylin