Nystad Mona, Sitras Vasilis, Larsen Merethe, Acharya Ganesh
Department of Clinical Medicine, Women's Health and Perinatology Research Group, Faculty of Health Sciences, University of Tromsø, Norway; Department of Obstetrics and Gynecology, University Hospital of North Norway, Tromsø, Norway.
Department of Clinical Medicine, Women's Health and Perinatology Research Group, Faculty of Health Sciences, University of Tromsø, Norway; Department of Obstetrics and Gynecology, University Hospital of North Norway, Tromsø, Norway; Department of Obstetrics, Oslo University Hospital-Rikshospitalet, Oslo, Norway.
Am J Obstet Gynecol. 2014 Dec;211(6):686.e1-31. doi: 10.1016/j.ajog.2014.06.047. Epub 2014 Jun 21.
The purpose of this study was to investigate the expression and subcellular localization of laeverin, a placenta-specific membrane-bound aminopeptidase, in preeclamptic placentas and its role in trophoblast cell migration and invasion.
Expression of laeverin was investigated in 6 normal and 6 preeclamptic placentas with the use of immunofluorescence, sodium dodecylsulfate-polyacrylamide gel electrophoresis with Western blot analysis and immunoelectron microscopy. The role of laeverin in trophoblast migration and invasion was studied with the use of the xCelligence system and Boyden chambers with Matrigel in HTR-8/SVneo cells. The effect of laeverin gene-silencing on selected genes that are involved in cell transformation and tumorigenesis was evaluated by polymerase chain reaction array. The Student t test, Mann-Whitney U test, χ(2) test, or F-test was used to compare groups as appropriate.
Laeverin was expressed in the cell membrane of villous trophoblasts in third-trimester healthy placentas; in preeclamptic placentas, it was expressed ectopically in the cytoplasm, especially in microvesicles. Immunoelectron microscopy showed laeverin leakage into the fetal capillaries and abundant expression in microvesicles in preeclamptic placentas. Migration and invasion of HTR-8/SVneo cells were reduced by 11.5% (P = .023) and 56.7% (P = .001), respectively, by laeverin gene-silencing. Analysis of downstream pathways affected by laeverin-silencing demonstrated significant down-regulation of integrin A2 (39-fold), integrin B3 (5-fold), and matrix metalloprotease 1 (36-fold).
Expression of laeverin protein is altered in preeclamptic placentas. Its ectopic expression in the cytoplasm and microvesicles, rather than the cell membrane and leakage into the fetal capillaries, may have a role in the pathophysiologic condition of preeclampsia. Laeverin gene appears to be involved in trophoblast cell migration and invasion through interaction with integrins and matrix metalloprotease 1.
本研究旨在探讨胎盘特异性膜结合氨肽酶laeverin在子痫前期胎盘中的表达、亚细胞定位及其在滋养层细胞迁移和侵袭中的作用。
采用免疫荧光、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳及蛋白质印迹分析和免疫电子显微镜技术，检测6例正常胎盘和6例子痫前期胎盘组织中laeverin的表达情况。利用xCelligence系统和铺有基质胶的Boyden小室，研究laeverin在HTR-8/SVneo细胞滋养层迁移和侵袭中的作用。通过聚合酶链反应芯片评估laeverin基因沉默对参与细胞转化和肿瘤发生的特定基因的影响。根据情况使用Student t检验、Mann-Whitney U检验、χ²检验或F检验对组间进行比较。
在妊娠晚期健康胎盘的绒毛滋养层细胞膜中表达laeverin；在子痫前期胎盘中，它在细胞质中异位表达，尤其是在微泡中。免疫电子显微镜显示，子痫前期胎盘中laeverin渗漏到胎儿毛细血管中，并在微泡中大量表达。laeverin基因沉默使HTR-8/SVneo细胞的迁移和侵袭分别降低了11.5%（P = 0.023）和56.7%（P = 0.001）。对受laeverin沉默影响的下游通路分析表明，整合素A2（39倍）、整合素B3（5倍）和基质金属蛋白酶1（36倍）显著下调。
子痫前期胎盘中laeverin蛋白表达发生改变。其在细胞质和微泡中的异位表达，而非在细胞膜中的表达以及渗漏到胎儿毛细血管中，可能在子痫前期的病理生理状况中起作用。Laeverin基因似乎通过与整合素和基质金属蛋白酶1相互作用参与滋养层细胞的迁移和侵袭。
