Ocular surface mucin-glycocalyx matrix

The ocular surface mucin-glycocalyx matrix is a complex, multi-layered structure that serves as the primary interface between the ocular surface epithelium and the tear film. It is composed of membrane-associated mucins (MAMs), such as MUC1, MUC4, and MUC16, which form the dense glycocalyx, and secreted mucins like MUC5AC that contribute to the mucoaqueous layer of the tears (1.1.1, 1.3.1). This matrix plays a vital role in maintaining ocular health by providing boundary lubrication, ensuring surface wettability, and acting as a physical and biochemical barrier against pathogens, allergens, and environmental debris (1.3.3, 1.3.5). Disruption of the mucin-glycocalyx matrix is a hallmark of ocular surface diseases, including dry eye disease and Sjögren's syndrome, where loss of mucin expression leads to tear film instability and chronic inflammation (1.2.2, 1.4.2). Pharmacological interventions aim to restore this matrix using mucin secretagogues, such as rebamipide and diquafosol, or through anti-inflammatory treatments that preserve epithelial integrity (1.4.1, 1.4.3). Additionally, emerging therapies like recombinant human lubricin are being investigated to supplement the matrix's lubricating properties and protect the ocular surface from frictional damage (1.4.4).

Other names

Ocular surface glycocalyxTear film mucin layerPre-ocular tear filmMucosal glycocalyx of the ocular surfaceOcular tear film mucin-glycocalyx matrix

The matrix is targeted through mucin secretagogues that stimulate the production of membrane-associated and secreted mucins, P2Y2 receptor agonists that promote goblet cell degranulation, and anti-inflammatory agents that prevent the degradation of the glycocalyx by reducing cytokine-mediated damage. Additionally, biolubricants and mucomimetic polymers are used to supplement the matrix's physical properties and restore surface wettability.