FIG 8.

Transmission electron microscopy demonstrates release and cellular tropism of A(H7N9) virus in differentiated primary human bronchial and tracheal epithelial cells. HTE cells were infected apically with Anhui/1 virus at an MOI of 1 and fixed at 24 h p.i. for examination by transmission electron microscopy. (A) Low-magnification view showing multiple layers of cells growing on a membranous insert (I). The arrow points to an area seen at higher magnification in panel B. G, goblet cell; C, ciliated cell. Bar, 2 μm. (B) Goblet cell with numerous extracellular spherical virions and one budding particle (arrow). M, mucin-containing granule. Bar, 100 nm. (C) Ciliated cell with released virions, and a particle (arrow) budding from microvillus. C, cilium. Bar, 500 nm.