CCL20 and Recurrent lower respiratory tract infections: has been suggested to stimulate epithelial cells to produce interleukin (IL)-8, IL-6, and chemokine (C-C motif) ligand 20 (CCL20) and promote mucosal T helper (Th) 17 immune responses and neutrophil recruitment in cases of chronic lung infection, causing the systemic spread of inflammatory mediators, bacteria, and bacterial products, which may influence systemic disease outcomes, such as rheumatoid arthritis and metabolic disorders [6].