Disruption of the endothelial cell protein C receptor gene in mice causes placental thrombosis and early embryonic lethality
Disruption of the endothelial cell protein C receptor gene in mice causes placental thrombosis and early embryonic lethality
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DOI：
10.1074/jbc.m207538200
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发表时间：
2002-11-08
影响因子：
4.8
通讯作者：
Esmon, CT
中科院分区：
文献类型：
--
作者：
Gu, JM;Crawley, JTB;Esmon, CT
内皮细胞蛋白C受体（EPCR）是主要在内皮上发现的1型跨膜蛋白，其以相似的亲和力结合蛋白C和活化蛋白C。EPCR通过凝血酶-血栓调节蛋白复合物增强蛋白C的活化。为了确定EPCR的生理重要性，我们通过在胚胎干细胞中同源靶向产生EPCR缺陷小鼠。EPCR+/-杂交后代的基因分型结果表明，EPCR-/-胚胎在胚胎第10.5天（E10.5）或之前死亡。逆转录PCR证实EPCR-/-胚胎中不存在EPCR mRNA。EPCR-/-胚胎在E7.5天从胚外膜和组织中取出，并在体外培养，超过E10.5，表明EPCR在胎盘和/或母胚界面的正常功能中的作用。免疫组化显示EPCR-/-胚胎滋养层巨细胞缺乏EPCR。这些细胞通常表达EPCR，与母体循环及其凝血因子直接接触。在EPCR-/-胚胎中，在这些细胞周围检测到纤维蛋白沉积大大增加。为了防止这种纤维蛋白沉积，EPCR+/-杂交的雌性小鼠在整个妊娠期间每天皮下注射依诺肝素。尽管一些EPCR-/-胚胎从妊娠中期致死率中挽救出来，但该方案未产生EPCR-/-幼崽。我们的结论是，EPCR是必要的正常胚胎发育。此外，EPCR在预防母胚界面血栓形成方面起着关键作用。
The endothelial cell protein C receptor (EPCR) is a type 1 transmembrane protein found primarily on endothelium that binds both protein C and activated protein C with similar affinity. EPCR augments the activation of protein C by the thrombin-thrombomodulin complex. To determine the physiological importance of EPCR, we generated EPCR-deficient mice by homologous targeting in embryonic stem cells. Genotyping of progeny obtained from EPCR+/- interbreeding indicated that EPCR-/- embryos died on or before embryonic day 10.5 (E10.5). Reverse transcriptase-PCR confirmed the absence of EPCR mRNA in EPCR-/- embryos. EPCR-/- embryos removed from extra-embryonic membranes and tissues at day E7.5 and cultured in vitro developed beyond E10.5, suggesting a role for EPCR in the normal function of the placenta and/or at the materno-embryonic interface. Immunohistochemistry revealed the lack of EPCR in trophoblast giant cells of EPCR-/- embryos. These cells, which normally express EPCR, are in direct contact with the maternal circulation and its clotting factors. In EPCR-/- embryos, greatly increased fibrin deposition was detected around these cells. To prevent this fibrin deposition, EPCR+/--crossed female mice received a daily subcutaneous injection of enoxaparin through pregnancy. Although some EPCR-/- embryos were rescued from midgestational lethality, this regimen yielded no EPCR-/- pups. We conclude that EPCR is essential for normal embryonic development. Moreover, EPCR plays a key role in preventing thrombosis at the maternal-embryonic interface.