Increased Infectivity of H5N1 Influenza Virus Figure 5. Viral sensitivity to the lysosomotropic agents chloroquine or NH4Cl. Pretreated Vero cells were infected with VN1203DNS1, VN1203DNS1-K58I, or seasonal BN/59/07 (H1N1) virus at moi 5 in a medium supplemented with chloroquine or NH4Cl at indicated concentrations. The infected cells were visualized by the immunostaining of influenza NP (5 h p.i.). doi:10.1371/journal.pone.0018577.g005 Figure 6. Growth curves on different cell lines. Vero (A), MDCK (B), A549 (C), or HBE (D) cells were infected with VN1203wtNS or VN1203wtNS- K58I virus at moi 0.001. Supernatants were collected at indicated time points and virus infectious titers were determined by TCID50 assay on Vero cells. doi:10.1371/journal.pone.0018577.g006 PLoS ONE | www.plosone.org 6 April 2011 | Volume 6 | Issue 4 | e18577