, Volume 188, Supplement 1, pp 69–72 | Cite as

The Role of Mucus in Cough Research

  • Bruce K. RubinEmail author


Cough is a defense mechanism for promoting airway hygiene when mucociliary clearance is ineffective due to increased mucus secretion, inflammation, infection, or ciliary dysfunction. Secretions can contribute to airflow limitation and chronic hypersecretion can worsen airway inflammation with retained inflammatory cells and mediators. The focus of the Second Annual Cough Conference has been on cough as a troublesome symptom; but to understand the importance and effectiveness of cough clearance, it is critical to understand airway secretions. The biophysical properties of mucus and phlegm determine how readily these secretions can be cleared by coughing.


Sputum Mucus Mucins Phlegm Cough Rheology Tenacity Mucolytics Expectorants 



Airway surface liquid


Cystic fibrosis


Cystic fibrosis transmembrane ion transport regulator


N-Acetyl l-cysteine


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Copyright information

© U.S. Government 2009

Authors and Affiliations

  1. 1.Department of PediatricsVirginia Commonwealth University School of MedicineRichmondUSA

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