Redl B
Institut für Mikrobiologie, Medizinische Fakultät, Universität Innsbruck, Fritz Pregl Strasse 3, A-6020 Innsbruck, Austria.
Biochim Biophys Acta. 2000 Oct 18;1482(1-2):241-8. doi: 10.1016/s0167-4838(00)00142-4.
Human tear prealbumin, now called tear lipocalin, was originally described as a major protein of human tear fluid, which was thought to be tear specific. However, recent investigations demonstrated that it is identical with lingual von Ebner's gland protein, and is also produced in prostate, nasal mucosa and tracheal mucosa. Homologous proteins have been found in rat, pig and probably dog and horse. Tear lipocalin is an unusual lipocalin member, because of its high promiscuity for relative insoluble lipids and binding characteristics that differ from other members. In addition, it shows inhibitory activity on cysteine proteinases similar to cystatins, a feature unique among lipocalins. Although it acts as the principal lipid binding protein in tear fluid, a more general physiological function has to be proposed due to its wide distribution and properties. It would be ideally suited for scavenging of lipophilic, potentially harmful substances and thus might act as a general protection factor of epithelia.
人泪前清蛋白，现称为泪脂质运载蛋白，最初被描述为人泪液中的一种主要蛋白质，被认为是泪液特有的。然而，最近的研究表明它与舌埃伯纳腺蛋白相同，并且也在前列腺、鼻黏膜和气管黏膜中产生。在大鼠、猪以及可能在狗和马中也发现了同源蛋白。泪脂质运载蛋白是一种不同寻常的脂质运载蛋白成员，因为它对相对不溶性脂质具有高度的混杂性以及与其他成员不同的结合特性。此外，它对半胱氨酸蛋白酶表现出类似于胱抑素的抑制活性，这是脂质运载蛋白中独有的特征。尽管它作为泪液中主要的脂质结合蛋白，但由于其广泛的分布和特性，必须提出更普遍的生理功能。它非常适合清除亲脂性的潜在有害物质，因此可能作为上皮组织的一种普遍保护因子。
