CD44 antigen (CD44) and Mucin family proteins (MUC) (CD44/MUC)

The CD44 antigen (CD44) and Mucin family proteins (MUC) represent a functional target system defined by non-specific mucoadhesive interactions, which are pivotal in both physiological barrier function and advanced drug delivery. CD44 is a transmembrane glycoprotein that acts as the primary receptor for hyaluronan, playing essential roles in cell-matrix adhesion, lymphocyte homing, and tumor metastasis (UniProt P16070). Mucins are a family of heavily O-glycosylated proteins that form the viscoelastic gel layer of mucus, protecting epithelial surfaces from mechanical stress and pathogens (NCBI NBK541059). Non-specific mucoadhesive interactions occur when polymers, such as hyaluronic acid or carbomers, adhere to these mucosal components through physical forces like hydrogen bonding and electrostatic attraction (PubMed 21430958). This interaction is therapeutically exploited to increase the contact time of drugs on ocular, buccal, and vaginal surfaces, thereby improving local bioavailability. In disease states, alterations in mucin expression or CD44 signaling are linked to conditions like dry eye syndrome, inflammatory bowel disease, and various epithelial cancers (PubMed 25139438). Consequently, targeting this system involves both the replenishment of the mucosal barrier and the utilization of CD44 as a docking site for targeted therapeutic vehicles.

Other names

Hyaluronan receptorHCAMPgp-1MucinsMucoadhesive interactionsHyaluronan receptor / mucins – non-specific mucoadhesive interactions

Mucoadhesion via physical entanglement and chemical bonding (hydrogen/electrostatic) with mucins and CD44 receptors to prolong drug residence time and provide lubrication.