Figure 6: Effect of MUC18 over-expression (OE) on human rhinovirus (HRV)-induced IL-8 production in cultured normal human primary tracheobronchial epithelial (NHTE) cells. Cells were transduced with MUC18 cDNA or green fluorescence protein (GFP) gene (control) encoded in replication-deficient lentivirus. After 72 hours of transduction, cells in 12-well plated were infected under submerged condition with HRV-1A (104 TCID50/well) for 4 and 24 hours. MUC18 OE cells, as compared to non-OE cells, show a greater induction of IL-8 protein (A) following HRV-1A infection at 4 hours. Data are expressed as means ± SEM. (B) – Net changes of IFN-β mNRA expression after HRV-1A in MUC18 OE cells versus (minus) cells without MUC18 OE. At 4 hours of HRV-1A infection, MUC18 OE significantly decreases the induction of IFN-β mNRA expression. N=4 human donors.