Mucus layer in airway

The mucus layer in the airways is **not a single protein or receptor**, but rather a complex gel-like barrier composed majorly of the secreted polymeric mucins MUC5B and MUC5AC, water, salts, lipids, and a variety of defense proteins[1][2][5]. It plays a critical role in **trapping inhaled particles, allergens, and pathogens**, enabling their clearance from the lung by coordinated ciliary movement (mucociliary clearance)[5][6]. The thickness, hydration, and composition of the mucus layer, regulated by epithelial ion transport and mucin secretion, are crucial for lung defense and efficient mucus clearance[3][4]. Diseases such as cystic fibrosis, COPD, and asthma involve dysregulation of this layer, often leading to increased viscosity and impaired clearance[1][5][6]. Pharmacological interventions mostly target **the mucus layer itself** to alter its hydration or viscosity, not a single molecular target as usually implied by "therapeutic target" in drug development. Note: - This entity is **not a canonical drug target** such as a receptor, enzyme, or transporter. Instead, it is a complex extracellular hydrogel structure. - If your intent is to refer to a specific molecular component (like MUC5AC, MUC5B, or a particular ion channel), you should specify that molecular target. - "Mucus layer in airway" is a functional/anatomical structure rather than a discrete biochemical therapeutic target[1][5][6].

Other names

Airway mucusAirway mucus layerMucus gelAirway surface liquid (in some contexts)

Mucolysis (hydrating or breaking down mucus to reduce viscosity) - Enhancing mucociliary clearance - Reducing secretion or hypersecretion of mucins