IFITM3 Clusters on Virus Containing Endosomes and Lysosomes Early in the Influenza A Infection of Human Airway Epithelial Cells

Kummer, Susann; Avinoam, Ori; Kräusslich, Hans-Georg

ection rate in this cell line and the fact that cytoplasmic NP was also observed in cells lacking the bright nuclear NP of replicating IAV (Figure 1A) , we suggest that early IFITM3 clustering at vesicular structures correlates with an abortive infection in this cell type, and that only cells that do not induce the vesicular clustering of IFITM3 become infected. In general, the IFITM3 signals were stronger in HSAEpCs compared to A549 cells ( Figure 5A,C) , and IFITM3 clusters apparently coating cytoplasmic vesicles were also present in productively IAV-infected cells exhibiting a strong nuclear NP signal in this case ( Figure 5D ). No IFITM3 clustering at vesicular structures was observed in HSAEpCs in the absence of IAV infection, while the overall IFITM3 signal intensity was much higher in these primary cells compared to A549 cells without infection ( Figure S5 ). Viruses 2019, 11, x FOR PEER REVIEW 10 of 17