IRF3 and IRF7 are members of the interferon regulatory transcription factor (IRF) family, involving in antiviral defense, cell growth regulation, and immune activation. Latent cytoplasmic IRF-3 and IRF7 are activated and phosphorylated following virus infection or treatment with dsRNA, and translocate to the nucleus and bind to their DNA binding sequences. Even though IRF3 and IRF7 are the key activators of the alpha/beta IFN genes, the recent studies have demonstrated that IRF3 and IRF7 have distinct DNA binding properties and induce preferentially on different promoters.  Because of the common and distinct biological features of IRF-3 and IRF-7, Signosis have developed both IRF3 and IRF7 ELISA kits respectively and a combined kit (48 wells for IRF3 and 48 wells for IRF7) with specific DNA binding sites and antibodies to distinguish the activation of IRF3 and IRF7 in various biological conditions.