Description
Lipocalin-1, also called tear lipocalin or von Ebner's gland protein, a member of the lipocalin superfamily that binds to a broad array of different chemical classes of lipophilic ligands, is believed to act as a physiological scavenger of putative harmful lipophilic ligands. Thus, it was thought to be produced exclusively by a number of exocrine glands and tissues, including lachrymal and lingual glands, prostate, secretory glands of the tracheobronchial tract, pituitary gland and sweat glands. It was also demonstrated to exhibit cysteine proteinase inhibition and nonspecific endonuclease activity in vitro. Lipocalin-1 concentration in tear fluid is decreased in patients with meibomian gland dysfunction. It was identified the first protein, lipocalin-1, in the secretome of human blastocysts that is associated with chromosome aneuploidy thus lipocalin-1 might be a potential marker for noninvasive aneuploidy screening. Lipocalin-1 secretion is up-regulated in the airways of patients with cystic fibrosis, by contrast, down-regulated in in dry eye syndrome, accompanying with decrease of prolactin-inducible protein, lactoferrin and lysozyme. Furthermore, lipocalin-1 was identified as a novel autoantigen target in Sjögren's syndrome. The major tear proteins; such as lipocalin-1, lactoferrin and lysozyme are involved in the immune and inflammatory processes and defense against pathogens