US EPA

2347418 

Journal Article 

A periciliary brush promotes the lung health by separating the mucus layer from airway epithelia 

Button, B; Cai, LH; Ehre, C; Kesimer, M; Hill, DB; Sheehan, JK; Boucher, RC; Rubinstein, M 

2012 

1 

Science
ISSN: 0036-8075
EISSN: 1095-9203 

337 

6097 

937-941 

English 

22923574 

10.1126/science.1223012 

Mucus clearance is the primary defense mechanism that protects airways from inhaled infectious and toxic agents. In the current gel-on-liquid mucus clearance model, a mucus gel is propelled on top of a "watery" periciliary layer surrounding the cilia. However, this model fails to explain the formation of a distinct mucus layer in health or why mucus clearance fails in disease. We propose a gel-on-brush model in which the periciliary layer is occupied by membrane-spanning mucins and mucopolysaccharides densely tethered to the airway surface. This brush prevents mucus penetration into the periciliary space and causes mucus to form a distinct layer. The relative osmotic moduli of the mucus and periciliary brush layers explain both the stability of mucus clearance in health and its failure in airway disease.