The role of commensals that are usually present not just in the lungs or the gut has often been underevaluated, and a study by Rigauts C. et al. [52] demonstrated that a commensal bacterium, Rothia mucilaginosa, which is normally present in the oral cavity but also found in the lower airways, inhibits inflammation by acting on the inhibition of NF-kB in chronic asthma as well as many other inflammatory diseases, such as COPD, cystic fibrosis (CF), and bronchiectasis. This evidence concerns the gene NFKB1 and cystic fibrosis.