https://doi.org/10.30702/Ophthalmology31032021-12.1.73-84/048.8
UDC 617.7:616-092.19:637.483(048.8)

Drozhzhyna G. I., Veliksar T. A.

The Filatov Institute of Eye Diseases and Tissue Therapy of NAMS of Ukraine, Odesa, Ukraine

Abstract
The main protective proteins that are synthesized by eye cells are lactoferrin (Lf), lysozyme, immunoglobulin-A, and tear lipocalins. It has been proven that Lf is contained in biological fluids and mucous membranes of various organs; this highlights the importance of this protein in the first line of defense from pathogenic microorganisms. Lf is a non-heme iron-binding chelating glycoprotein from the transferrin family. Lf carries out bactericidal, fungicidal, antiviral, antioxidant and transport functions, prevents the formation of free radicals, inhibits lipid peroxidation, activates enzymes of the antioxidant system.
Lf is contained in tears in the highest concentration (about 2 mg/ml, 25% of tear proteins), the average concentration is 1.42 mg/ml. Lf is an important component providing homeostasis of the ocular surface, modulates the activity of T-lymphocytes and macrophages in infections, prevents the multiplication of pathogenic microflora, the development of inflammation, protects the integrity of the cornea, promotes healing from microtraumas, controls the level of iron in the lacrimal fluid, and protects against toxins. These properties of Lf open up prospects for its application in the treatment of chronic diseases of the ocular surface and, in particular, dry eye disease. Lf concentration in tears decreases during sleep, with age, in dry eye disease, keratitis and conjunctivitis, when using contact lenses, that increase the risk of developing eye infections.
The first results of the application of ophthalmic drops Lacto (NOVAX® PHARMA) showed good tolerance and therapeutic efficacy in the treatment of inflammatory diseases of the ocular surface.

Keywords: lactoferrin, tear, antimicrobial, immunomodulatory, anti-inflammatory properties, ocular surface.