CD44 antigen (CD44) (CD44)

CD44 is a transmembrane glycoprotein that serves as the primary cell-surface receptor for hyaluronic acid (HA) (UniProt: P16070). In the context of the ocular surface, CD44 is highly expressed on corneal and conjunctival epithelial cells, where it mediates essential processes such as cell adhesion, migration, and wound healing (PubMed: 25603161). The interaction between HA and CD44 is vital for maintaining the structural integrity of the ocular surface and the stability of the tear film. In pathological states like dry eye disease or corneal erosions, CD44-mediated signaling helps restore the epithelial barrier by promoting the migration of healthy cells to the site of injury (PubMed: 21871716). Binding of HA to CD44 also triggers anti-inflammatory pathways that help mitigate ocular surface damage. Therapeutically, HA-based eye drops utilize this interaction to provide lubrication and accelerate the recovery of the corneal epithelium. Additionally, CD44 is involved in regulating inflammatory pathways on the ocular surface, making it a key target for treating various ocular surface disorders. Beyond the eye, CD44 is involved in lymphocyte activation and cancer metastasis, which necessitates careful consideration in systemic drug development.

Other names

HCAMPgp-1Hermes antigenHyaluronate receptorPhagocytic glycoprotein 1Extracellular matrix receptor IIIECMR-IIIHUTCH-I

Binding of hyaluronic acid to CD44 receptors on the ocular surface promotes epithelial cell migration, proliferation, and survival, while also modulating inflammatory responses and maintaining tear film stability (PubMed: 12114273).