Fig. 2

Influenza A virus (IAV) and S. epidermidis induce the expression of interferon (IFN) and IFN-stimulated genes (ISGs). Normal human nasal epithelial (NHNE) cells were inoculated with nasal mucus-derived S. epidermidis (N1, N2, N3, N4) at a multiplicity of infection (MOI) of 0.25. a Levels of mRNAs encoding IFNs were monitored by real-time PCR. b NHNE cell supernatants were assayed by ELISA for levels of secreted IFN-λ following S. epidermidis infection. IFN-λ mRNA abundance (c), IFN-λ protein levels (d), and ISG mRNA levels (e) were also assessed in NHNE cells infected with S. epidermidis and/or IAV. IAV PA mRNA levels (f) and viral titers (g) were also measured in NHNE cells which were transfected with control shRNA or IL28R shRNA. Results are presented as the mean ± SD from four independent S epidermidis experiments. *p < 0.05 compared with control NHNE cells. **p < 0.01 compared with NHNE cells infected with IAV alone