Mucus and mucin network interfaces

The mucus and mucin network interfaces represent the complex structural and functional barrier formed by large, highly glycosylated proteins known as mucins. These networks are primarily composed of secreted gel-forming mucins, such as Mucin-5AC (MUC5AC) and Mucin-5B (MUC5B), which cross-link via disulfide bonds to create a viscoelastic gel (Thornton & Sheehan, 2004). This gel serves as a critical innate immune defense, trapping pathogens and particulates while maintaining hydration of the underlying epithelium (Fahy & Dickey, 2010). In diseases like cystic fibrosis, chronic obstructive pulmonary disease (COPD), and asthma, the mucin network becomes pathologically thickened or dehydrated, leading to impaired clearance and chronic infection (Balsamo et al., 2010). Therapeutic strategies targeting these interfaces include mucolytics that break chemical cross-links, osmotic agents that improve hydration, and mucoadhesive systems designed to enhance drug residence time at mucosal surfaces (Khutoryanskiy, 2011). Additionally, the interface between the mucus layer and the underlying periciliary layer is crucial for effective mucociliary transport. Drugs like N-acetylcysteine directly target the chemical integrity of the mucin network to reduce viscosity. Understanding the biophysical properties of these interfaces is essential for developing effective treatments for respiratory, gastrointestinal, and ocular disorders.

Other names

Mucus barrierMucin gelMucin glycoproteinsExtracellular mucin networkMucus-mucin complex

Reduction of disulfide bonds between mucin monomers to decrease viscosity, enzymatic degradation of extracellular DNA within the mucus matrix, or osmotic hydration of the mucus gel to facilitate clearance.