Figure 4. Diagram showing signal transduction events in human nasal epithelial cells (HNECs) infected with RSV. The replication and budding of RSV and the epithelial cell responses in HNECs infected with RSV are regulated via a PKCδ–HIF-1α–NF-ϰB pathway. The PKCδ–HIF-1α–NF-ϰB pathway, via TGF-ß in an autocrine manner, may also be important in epithelial cell responses at a late stage after RSV infection.