Source of the Placental Microbiome

人类相关微生物（“微生物组”）的数量超过了 人类细胞至少10倍，集体基因组（“宏基因组”）超过我们的人类基因组 基因含量增加了150倍以上。我们和其他人最近已经证明，细菌是 使用各种可培养和不可培养的方法在胎盘中检测到。几年来，我们 已经开发并使用宏基因组学来表征胎盘微生物组，并观察到 在其社区成员和他们的功能的变化凭借分娩时的胎龄。但 仍然不清楚胎盘微生物组的不同母体来源是什么，以及它是否下沉 通过羊膜腔内输送给胎儿，因此可在羊水中测量。 作为对人类胎盘项目的回应，我们建议确定 胎盘微生物组采用两个大型，强大和良好表征的现有数据集。我们将产生 无与伦比的宏基因组学和代谢组学数据，以检验我们的中心假设，即胎盘是 由主要来自母体口腔和GI社区的肠道微生物群组成， 阴道的贡献较小。我们进一步假设，胎盘微生物在胎儿中繁殖， 子宫内环境，并在中期妊娠羊水中检测到。此外，它们的代谢产物 作为微生物功能存在的持久标志。 为了证明这一假设，我们将在总共超过1230个受试者中执行三个基本目标 两个现有数据集的样本。完成这些目标的最终结果将是首先确定 胎盘微生物群的母体来源，并使用最先进的单分子验证这些发现 荧光原位杂交和培养。我们将在早期和中期总结这些发现。 中期妊娠羊水，从而确定胎盘微生物群下沉的早期证据。在最终 目的是，我们将使用LC/MS全光谱代谢组学对这些相同的受试者样本，以确定稳定的， 微生物组的持久代谢足迹。我们提出了我们的概念证明工作的肝内胆汁淤积 怀孕作为我们的方法的可行性，意义和准备翻译应用的证据。 作为一个成熟的团队围产期医生科学家的重点和历史的前沿， 大数据（特别是宏基因组学）科学，我们现在正处于独特的准备进行复杂的整合， 这些独特的研究数据集是可行的，合理的，可能具有长期意义， 冲击

Human-associated microorganisms (the “microbiome”) are present in numbers exceeding the quantities of human cells by at least 10-fold, and the collective genome (the “metagenome”) exceeds our human genome in terms of gene content by more than 150-fold. We and others have recently demonstrated that bacteria are detected in the placenta using a variety of culturable and non-culturable approaches. For several years we have developed and employed metagenomics to characterize the placental microbiome, and observed variation in its community membership and their function by virtue of gestational age at delivery. However, it remains unknown what the different maternal source(s) are of the placental microbiome, and whether it sinks to the fetus via the intra-amniotic cavity and thus is measureable in amniotic fluid. In response to the Human Placental Project, we propose to identify the sources and sinks for and of the placental microbiome employing two large, robust and well characterized existing datasets. We will generate unparalleled metagenomics and metabolomics data, in order to test our central hypothesis that the placenta is populated by commensal microbiota which largely arise from the maternal oral and GI communities, with a lesser contribution from the vagina. We further hypothesize that placental microbes populate the fetus and the intrauterine environment, and are detectable in mid-trimester amniotic fluid. Moreover, their metabolites serve as lasting signatures of the microbiotas functional presence. In order to prove this hypothesis, we will execute three essential aims in a total of over 1230 subjects samples from two existing data sets. The net result of the completion of these aims will be to first identify the maternal source of the placental microbiota, and validate these findings using state of the art single molecule fluorescent in situ hybridization and culturation. We will thereafter recapitulate these findings in early and mid- second trimester amniotic fluid and thus identify the early evidence of the placental microbiota sink. In a final aim, we will use LC/MS full spectral metabolomics on these same subjects samples to identify the stable and lasting metabolic footprint of the microbiome. We present our proof of concept work on intrahepatic cholestasis of pregnancy as evidence for the feasibility, significance and ready translational application of our approach. As a proven team of perinatal physician scientists with an emphasis and history of being at the forefront of big data (and notably metagenomics) science, we are uniquely poised to now undertake complex integration of these unique data sets in studies which are feasible, justifiable, and of likely long-term significance and high impact.