TLR2 and cystic fibrosis: Many studies have demonstrated the increased activation of TLR2, TLR4, and TLR5 in CF airway epithelial cells and macrophages, which contributes to a hyperinflammatory response toward bacterial peptidoglycan (PGN), lipopeptides, lipopolysaccharide (LPS), and flagellin from Staphylococcus aureus and Pseudomonas aeruginosa that are important pathogens in pulmonary infections in CF [11,12,13,14,15,16,17].