Moreover, CF patients display increased TLR5 levels in airway neutrophils than controls and patients with non-CF bronchiectasis (Koller et al., 2008), while TLR5–/– mice exposed to flagellated PA displayed reduced neutrophil recruitment as compared with both wild-type mice and TLR5–/– mice challenged with non-flagellated PA (Morris et al., 2009), further underlining the specific contribution of TLR5/flagellin interaction to inflammation in CF. This evidence concerns the gene TLR5 and cystic fibrosis.