Mucus (upper respiratory tract)

Mucus in the upper respiratory tract is a complex, viscous secretion produced primarily by goblet cells and submucosal glands lining the airways. Its primary functions include trapping inhaled pathogens and particulates, protecting the airway epithelium from environmental insults, facilitating removal via mucociliary clearance, and contributing to immune defense. The major macromolecular components are gel-forming mucins (mainly MUC5AC and MUC5B). Changes in mucus quality, such as in hyperconcentration, dehydration, or overproduction, play a key role in several airway diseases, including cystic fibrosis, chronic obstructive pulmonary disease, bronchiectasis, and asthma. Mucus itself is not a classical drug target; rather, therapies act on its physical properties or underlying regulation, not on “mucus” as a single molecule or receptor.

Other names

Respiratory mucusairway mucusphlegm (when expelled)sputum (when expectorated)tracheobronchial mucus

Disruption of mucin polymers to decrease viscosity - Hydration of mucus to enhance clearance - Restoration of ion transport/airway surface hydration (in CF)