Critical Role of HAX-1 in Promoting Avian Influenza Virus Replication in Lung Epithelial Cells

Figure 3

HAX-1 promoted H9N2 influenza virus replication in the lung epithelial cells. (a) Generation of human lung epithelial cell lines with decreased HAX-1 expression through shRNA knockdown in A549 cells. The cells were infected with the lentiviruses and shRNA-expressing cells selected under puromycin pressure, and the HAX-1 knockdown cell lines (shRNA1 and shRNA2) were confirmed, in comparison to the cells with the scramble shRNA (scramble) or cells not transduced (−), with a real-time RT-PCR for HAX-1 mRNA transcript levels. Expression of HAX-1 in knockdown cells was also shown in a western blot analysis. (b–d) Decreased influenza virus replication in HAX-1 knockdown cells. HAX-1 knockdown and control A549 cells were infected with the H9N2 virus at MOI of 0.01, 0.1, or 1.0, and the cultural medium was titrated in MDCK cells with a plaque assay. The titration was performed with duplicates, and the mean titers were exhibited.

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