Figure 2
From: Experimental infection of hamsters with avian paramyxovirus serotypes 1 to 9
Representative histopathologic lesions in sections of lung (a-d) and nasal turbinates (e, f) from hamsters 3 dpi with APMV-1 (a, b), APMV-2 (c), APMV-7 (d) and APMV-9 (e, f). Lungs (g) and nasal turbinates (h) from uninfected hamster. (hematoxylin and eosin staining, magnification, ×400). (a) Section of lung infected with APMV-1. The bronchiolar and bronchial epithelia are multifocally hyperplastic (yellow arrow) and contain sloughed cellular debris and inflammatory cells (black arrow). There are moderate numbers of necrotic cells in the bronchiolar epithelium and in areas of inflammation in alveoli. (b) Section of lung infected with APMV-1. There is multifocal infiltration and consolidation of the pulmonary interstitium by moderate numbers of lymphocytes, monocytes, and neutrophils (black arrow), with an accumulation of inflammatory cells in alveoli (yellow arrow). Multifocally, alveoli are lined by rows of hyperplastic epithelial cells (white arrows) that sometimes exhibit cellular atypia, including anisocytosis, anisokaryosis, and cytomegaly (atypical type II pneumocyte hyperplasia). (c) Section of lung infected with APMV-2. The pulmonary interstitium is multifocally infiltrated by moderate numbers of lymphocytes, monocytes, and neutrophils (white arrows). (d) Section of lung infected with APMV-7. The pulmonary interstitium is multifocally infiltrated and consolidated by moderate numbers of lymphocytes, monocytes, and neutrophils (black arrow), with accumulations of inflammatory cells in alveoli. Multifocally, alveoli are lined by rows of hyperplastic epithelial cells (white arrow), with some areas exhibiting cellular atypia, including anisocytosis, anisokaryosis, and cytomegaly (atypical type II pneumocyte hyperplasia). The bronchiolar and bronchial epithelia are multifocally hyperplastic (yellow arrow). There are moderate numbers of necrotic cells in bronchiolar epithelium and in areas of inflammation in alveoli. (e) Section of nasal turbinate infected with APMV-9. There is massive cell death and necrosis of the epithelial tissue lining the turbinate bone (white arrow). There is no appreciable level of inflammatory cells in the surrounding tissues. (f) Section of nasal turbinate infected with APMV-3, showing necrotic tissue, loss of ciliary tissue, and blunting of cilia (white arrow). (g) Section of lung from a mock infected hamster (control). (h) Section of nasal turbinate from a mock infected hamster (control).