Cystic Fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene resulting in defective CFTR-mediated chloride transport, dysregulation of epithelial sodium channels (ENaC) and exaggerated innate immune responses. We tested the hypothesis that upregulation of ENaC drives autoinflammation in this complex monogenic disease.We show that monocytes from patients with CF exhibit a systemic proinflammatory cytokine signature, with associated anti-inflammatory M2-type macrophage deficiency. Cells harboring CF mutations are hyperresponsive to NLRP3 stimulation, as evidenced by increased IL-18, IL-1ļ¢, ASCspecks levels in serum and caspase-1 activity in monocytes, and by increased IL-18 production and caspase-1 activity in bronchial epithelial cells (BECs). In both cell types there is an associated shift to glycolytic metabolism with succinate release, in response to increased energy requirements. Inhibition of amiloride-sensitive sodium channels partially reverses the NLRP3-dependent inflammation and metabolic shift in these cells. Overexpression of ļ¢-ENaC, in the absence of CFTR dysfunction, increases NLRP3-dependent inflammation, indicating a CFTR-independent ENaC-axis in CF pathophysiology. Sodium channel modulation provides an important therapeutic strategy to combat lung inflammation in CF. Philip Hopkins (Leeds) for instrumental strategic support. Salvesen GS, Morris LX et al. (2015) Caspase-11 cleaves gasdermin D for non-canonical inflammasome signalling. Nature 526: 666-71 Keiser NW, Birket SE, Evans IA, Tyler SR, Crooke AK, Sun X, Zhou W, Nellis JR, Stroebele EK, Chu KK, Tearney GJ, Stevens MJ, Harris JK, Rowe SM, Engelhardt JF (2015) Defective innate immunity and hyperinflammation in newborn cystic fibrosis transmembrane conductance regulatorknockout ferret lungs. Am J Respir Cell Mol Biol 52: 683-94 Kelly B, O'Neill LAJ (2015) Metabolic reprogramming in macrophages and dendritic cells in innate immunity. Cell Research 25: