A549-Dual™ KO-RIG-I cells were generated from A549-Dual™ cells through the stable knockout of the RIG-I gene. They are adherent epithelial cells derived from the human A549 lung carcinoma cell line by stable integration of two inducible reporter constructs. The A549 cell line, a cellular model for asthma and respiratory infections, expresses many pattern recognition receptors (PRRs), including RIG-I [1, 2], and the Toll-like receptors (TLRs) TLR2 [3], TLR3 and TLR5 but not TLR4 [3].

A549-Dual™ KO-RIG-I and A549-Dual™ cells express a secreted embryonic alkaline phosphatase (SEAP) reporter gene under the control of the IFN-β minimal promoter fused to five NF-κB binding sites. They also express the secreted Lucia luciferase reporter gene under the control of an ISG54 minimal promoter in conjunction with five IFN-stimulated response elements. As a result, they allow to simultaneously study the NF-kB pathway, by assessing the activity of SEAP, and the interferon regulatory factor (IRF) pathway, by monitoring the activity of Lucia luciferase. Both reporter proteins are readily measurable in the cell culture supernatant when using QUANTI-Blue™ Solution, a SEAP detection reagent, and QUANTI?Luc™ 4 Lucia/Gaussia, a Lucia and Gaussia luciferase detection reagent.