Teng Christina T, Beard Clara, Gladwell Wesley
Gene Regulation Section, Laboratory of Reproductive and Developmental Toxicology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA.
Biol Reprod. 2002 Nov;67(5):1439-49. doi: 10.1095/biolreprod.101.002089.
Lactoferrin, an iron-binding glycoprotein, kills bacteria and modulates inflammatory and immune responses. Presence of lactoferrin in the female reproductive tract suggests that the protein may be part of the mucosal immune system and act as the first line of defense against pathogenic organisms. We have discovered that lactoferrin is a major estrogen-inducible protein in the uterus of immature mice and is up-regulated by physiological levels of estrogen during proestrous in mature mice. In the present study, we examined lactoferrin gene expression and its response to estrogen stimulation in the female reproductive tract of several strains of immature mouse, rat, and hamster. The lactoferrin expression in the cycling adult female rat was also evaluated. Lactoferrin gene polymorphism exists among the different mouse strains. In the three inbred mouse strains studied, lactoferrin gene expression is stimulated by estrogen in the immature uterus, although it is less robust than in the outbred CD-1 mouse. We found that the lactoferrin gene is constitutively expressed in the epithelium of the vagina and the isthmus oviduct; however, it is estrogen inducible in the uterus of immature mice and rats. Furthermore, lactoferrin is elevated in the uterine epithelium of the mature rat during the proestrous and estrous stages of the estrous cycle. Estrogen stimulation of lactoferrin gene expression in the reproductive tract of an immature hamster is limited to the vaginal epithelium. The present study demonstrates differential expression and estrogen responsiveness of the lactoferrin gene in different regions of the female rodent reproductive tract and variation among the rodent species studied.
乳铁蛋白是一种铁结合糖蛋白，具有杀菌作用，并能调节炎症和免疫反应。女性生殖道中存在乳铁蛋白，这表明该蛋白可能是黏膜免疫系统的一部分，充当抵御致病生物的第一道防线。我们发现，乳铁蛋白是未成熟小鼠子宫中主要的雌激素诱导蛋白，在成熟小鼠发情前期，其表达会因雌激素的生理水平而上调。在本研究中，我们检测了几种未成熟小鼠、大鼠和仓鼠品系的雌性生殖道中乳铁蛋白基因的表达及其对雌激素刺激的反应。我们还评估了成年雌性大鼠发情周期中乳铁蛋白的表达情况。不同小鼠品系之间存在乳铁蛋白基因多态性。在所研究的三个近交小鼠品系中，未成熟子宫中的乳铁蛋白基因表达受雌激素刺激，尽管其反应强度不如远交系CD-1小鼠。我们发现，乳铁蛋白基因在阴道和输卵管峡部的上皮细胞中持续表达；然而，在未成熟小鼠和大鼠的子宫中，它是雌激素诱导型的。此外，在发情周期的发情前期和发情期，成年大鼠子宫上皮中的乳铁蛋白水平会升高。雌激素对未成熟仓鼠生殖道中乳铁蛋白基因表达的刺激仅限于阴道上皮。本研究证明了乳铁蛋白基因在雌性啮齿动物生殖道不同区域的差异表达和雌激素反应性，以及所研究啮齿动物物种之间的差异。
