Fig. 3

Histological lesions after chronic P. aeruginosa infection in mice. Mice were infected with 2x10⁶ cfu/lung of P. aeruginosa RP73 strain embedded in agar beads and lung harvested after 14 days from challenge. Histopathological analysis of lungs chronically infected by RP73 strain are characterised by acute and chronic lesions; the pulmonary parenchyma is infiltrated by macrophages, lymphocytes and some neutrophils (a). Agar beads (arrow) containing bacteria macrocolonies (*) are localised in the bronchia and surrounded by a massive neutrophils inflammation (b). Alcian blue staining shows mucus secretory cells hyperplasia (circle) (c)