Tear film component

Tear film components refer to the collective mixture of molecules constituting the tear film, rather than a single molecule or receptor[3][1][2]. The tear film is composed of three main layers: the outer lipid layer (produced by meibomian glands, glands of Moll and Zeiss), the middle aqueous layer (secreted by lacrimal glands), and the inner mucin layer (from goblet cells)[1][4]. Key molecular components include proteins (lysozyme, lactoferrin, lipocalin, secretory IgA), lipids (cholesterol, triglycerides, fatty acids, phospholipids), glycoproteins, and mucins[4][3][1]. These components work together to protect the ocular surface, provide lubrication, support immune defense, promote epithelial healing, and maintain the stability of the tear film[3][1]. Disruption in any layer or component may lead to ocular surface disorders, most notably dry eye disease, meibomian gland dysfunction, or increased susceptibility to infection[2][4]. The term "Tear film components" is not a specific molecule or canonical receptor, enzyme, transporter, or single drug target, but is rather an umbrella term for the collective biochemical constituents of the tear film, thus it is not considered a therapeutic target according to standard drug development definitions[3][1][2].

Other names

Tear filmTear componentsTear fluid components

Lubrication (artificial tears); Immunosuppression (cyclosporine, corticosteroids); Lymphocyte function antagonism (lifitegrast); Antimicrobial action (antibiotics)