Fig 11. Confirmation of results obtained in the A549 cell line by experiments in primary human small airway epithelial cells (HSAEC).

Experiments were performed as described for A549 cells in the Materials and Methods section and the preceding Figure legends. (A) siRNA knockdown in HSAEC using ATP1A1 siRNAs 1, 2, and 3 and Neg. siRNAs 1 and 2, analyzed 48 h p.t., by Western blot analysis as in Fig 1B. (B) Efficiency of RSV infection in HSAEC cells following knockdown of ATP1A1 expression using the indicated siRNAs, assayed by GFP quantification by ELISA reader, as in Fig 2A. (C) EGFR Tyr845 phosphorylation in HSAEC cells following knockdown of ATP1A1 expression using ATP1A1 siRNA 2, as in Fig 8. (D) Inhibition of RSV-GFP infection in HSAEC cells treated with 3.1 nM ouabain or 3.1 μM PST2238, evaluated by the expression of GFP as in Fig 5B. The IC₅₀ values of ouabain and PST2238 for inhibiting RSV infection were 5- and 8-fold lower than for A549 cells, respectively (S3A and S3B Fig). (E) ATP1A1 clustering and colocalization with RSV N protein in HSAEC cells, in an experiment performed as in Fig 3. Scale bar 10 μm.