Probing and modeling decidual natural killer cells in preterm birth

项目总结/摘要 人胎盘是一种半同种异体组织，其生长和发育需要胎盘细胞的耐受性。 母体免疫系统在自发性早产的情况下，这种关系如何受到损害 目前尚不清楚sPTB。在正常妊娠中，胎盘细胞与母体血液密切接触， 而子宫组织在整个妊娠期仍能逃避免疫识别。在此期间，产妇 免疫系统维持对外来胎儿同种异体抗原的耐受平衡，同时分期 对母胎界面潜在病原体的反应这种母胎细胞的性质 相互作用知之甚少，特别是当它在自发性早产的情况下出错时 （sPTB）。子宫内膜，称为蜕膜，是一个特别缺乏研究的微环境，含有许多 母体免疫细胞，其中蜕膜自然杀伤（dNK）细胞是最丰富的。在这个界面上 绒毛外滋养层（EVT）的胎盘细胞与母体免疫细胞密切接触。 胎儿EVT侵入蜕膜是母体子宫内膜适当重塑所必需的，包括 血管重塑，导致母体血液流向胎盘。之间的相互作用 已知胎盘EVT和蜕膜白细胞，如dNK，通过以下方式促进母体血管重塑： EVT并限制EVT侵入子宫壁的程度。事实上，sPTB的问题可能是由于 dNK细胞的不适当反应。不幸的是，dNK功能，包括dNK-滋养层串扰， 难以在正在进行的妊娠中进行研究，因为缺乏进入蜕膜室的途径， 发生了重要的相互作用。此外，很少有研究在妊娠时描述dNK的特征。 结果已知。虽然动物模型为这些过程提供了一些见解，但它们并不准确。 模拟人类胎盘形成和妊娠。该提案旨在从功能和转录组学上表征 足月dNK亚群，有或没有分娩，以及早产胎盘，然后使用诱导多能干细胞 细胞（iPSC）来模拟dNK，在足月和早产的情况下。我们的团队已经建立了优化的 iPSC分化为外周血NK细胞和EVT的方法。我们现在将优化一个协议 对于iPSC分化为蜕膜NK细胞，将其直接与原代细胞进行比较。成功完成 这一提议的结果将揭示异常dNK激活有助于 目的：建立一种可更新的、可操作的人dNK模型， 母胎界面

Project Summary/Abstract The human placenta is a semi-allogeneic tissue whose growth and development requires tolerance by the maternal immune system. How this relationship is compromised in the setting of spontaneous preterm birth (sPTB) is currently unknown. In a normal pregnancy, placental cells come in close contact with maternal blood and uterine tissues yet are able to evade immune recognition throughout gestation. During this time, the maternal immune system maintains a balance of tolerance toward foreign fetal alloantigens while simultaneously staging a response to potential pathogens at the maternal-fetal interface. The nature of such maternal-fetal cellular interactions is poorly understood, particularly when it goes awry in the setting of spontaneous preterm birth (sPTB). The uterine lining, called decidua, is a particularly understudied microenvironment, containing many maternal immune cells, of which decidual natural killer (dNK) cells are the most abundant. It is at this interface where placental cells called extravillous trophoblast (EVT) come in close contact with maternal immune cells. Invasion of the decidua by fetal EVT is required for proper remodeling of the maternal uterine lining, including vascular remodeling which leads to establishment of maternal blood flow to the placenta. Interactions between placental EVT and decidual leukocytes, such as dNK, are known to facilitate maternal vascular remodeling by EVT and limit the extent of EVT invasion into the uterine wall. Indeed, problems in sPTB could result from inappropriate responses by dNK cells. Unfortunately, dNK function, including dNK-trophoblast crosstalk, is difficult to study in an ongoing pregnancy, due to lack of access to the decidual compartment, where these important interactions occur. Additionally, very few studies have characterized dNK at term when the pregnancy outcome is known. While animal models have offered some insights into these processes, they do not accurately model human placentation and pregnancy. This proposal aims to functionally and transcriptomically characterize dNK subpopulation(s) in term, with or without labor, and preterm placenta, then use induced pluripotent stem cells (iPSC) to model dNK, in the setting of both term and preterm birth. Our team has established optimized methods for differentiation of iPSC into both peripheral blood NK cells and EVT. We will now optimize a protocol for iPSC differentiation into decidual NK cells, comparing them directly to primary cells. Successful completion of this proposal will reveal underlying mechanisms through which abnormal dNK activation contributes to spontaneous preterm birth, and establish a renewable and manipulatable model of dNK at the human maternal-fetal interface.