TNF and cystic fibrosis: Recently, IL-17, produced by T lymphocytes, has been reported to be associated with pathological processes in asthma, cystic fibrosis, and COPD, where it induces neutrophil-mediated inflammation by stimulating IL-6, tumor necrosis factor-α (TNF-α), G-CSF, and granulocyte‒macrophage colony‒stimulating factor (GM‒CSF) [10, 14, 15].