Figure 3

Pulmonary inflammation after SWCNT and/or T. gondii exposure. Representative photomicrographs of pulmonary changes in mouse lungs. A. High magnification image of an airway containing a large amount of pigmented particulate matter both free and within macrophages. The macrophages surround the material forming a small granuloma and spread out of the airway into adjacent alveoli. There is mild epithelial hyperplasia (arrow). B. High magnification view of a lung characteristic of those infected with T. gondii with loss of alveolar spaces due to pyogranulomatous inflammation and alveolar necrosis with intra-lesional protozoal vacuoles (inset). C. Lung from a mouse administered SWCNT and infected with the higher dose of T. gondii. There is focally extensive pleuritis (arrow), one large area of inflammation obliterating normal pulmonary architecture (box) and multifocal smaller nodules. D. Higher magnification view of the boxed area in (C) shows a combination of particle-laden macrophages filling airways (large arrow) and mild epithelial hyperplasia (small arrow). This is combined with vasculitis (asterisk) and necrosis with a pyogranulomatous inflammatory cell infiltrate as seen in the T. gondii infected animals.