IRF1 is a transcriptional regulator of ZBP1 promoting NLRP3 inflammasome activation and cell death during influenza virus infection

Innate immune sensing of influenza A virus (IAV) induces activation of various immune effector mechanisms including the NLRP3 inflammasome and programmed cell death pathways. Although type I IFNs are identified as key mediators of inflammatory and cell death responses during IAV infection, the involvement of various IFN-regulated effectors in facilitating these responses are less studied. Here, we demonstrate the role of interferon regulatory factor 1 (IRF1) in promoting NLRP3 inflammasome activation and cell death during IAV infection. IRF1 functions as a transcriptional regulator of Z-DNA binding protein 1 (ZBP1, also called as DLM1/DAI), a key molecule mediating IAV-induced inflammatory and cell death responses. Therefore, our study identified IRF1 as an upstream regulator of NLRP3 inflammasome and cell death during IAV infection and further highlights the complex and multilayered regulation of key molecules controlling inflammatory response and cell fate decisions during infections. We used microarrays to explore the gene expression profiles differentially expressed in influenza-infected bone marrow derived macrophages (BMDM) isolated from Ifnar1-/- , IRF1-/- and wild-type mice.