TNF and cystic fibrosis-related liver disease: PMNs are found accumulated within the airways where they are disabled in their capacity to remove infective agents; nevertheless, their activation is a hallmark of CFLD, together with increased concentrations of pro-inflammatory mediators, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, IL-8, IL-17, IL-33, and granulocyte-macrophage colony-stimulating factor (GM-CSF) [28].