Non-invasive analysis of methylated cell free DNA in necrotizing enterocolitis

项目总结/摘要 坏死性小肠结肠炎（NEC）是早产儿的一种毁灭性并发症， 显著的发病率和高死亡率，对此不存在生物标志物。NEC的高死亡率 如果有一种筛查方法可以早期发现疾病的话，预测和 NEC的预后工具对于推进我们对非侵入性的生物学见解至关重要 检测和准确及时的表型分型。我们开发了一个NEC生物储存库， 样本类型和广泛的临床元数据， NEC的发展。这些样本使我们能够询问NEC发展的基础机制， 包括遗传或环境因素。这些因素包括表观遗传机制，调节重要的 细胞分化和肠道发育方面。重要的是，表观遗传机制，特别是，在 在新生儿NEC期间发生的DNA甲基化水平是未知的。我们初步的表观基因组 数据表明在NEC期间许多生物学途径被改变。基于这些发现，我们现在 假设甲基化标记非侵入性鉴定可以鉴定处于坏死风险中的婴儿 肠炎我们将通过定义和量化粪便中的DNA甲基化特征来测试这一假设， 在NEC发生之前、期间和之后，早产儿的血液。此外，我们将扩大我们的 观察到多个关键通路的失调是NEC的一个定义性致病特征，并使用我们的 小鼠模型，以获得对NEC病理生物学的额外机制见解。在提案结束时， 我们将从婴儿的整个时间过程中产生大量的基因组数据， NEC的发展和表现，以及早产儿的正常子宫外发育期间。 这些研究将促进我们对NEC过程中所涉及的通路的表观基因组调控的理解。 此外，还可以解释早产儿对NEC的独特易感性，并确定 一种非侵入性的方法来诊断这种毁灭性的疾病。

Project Summary/Abstract Necrotizing enterocolitis (NEC) is a devastating complication of prematurity that develops suddenly and carries significant morbidity and a high mortality rate for which no biomarkers exist. The high mortality rate seen in NEC could likely be prevented if there was a screening method that permitted early disease detection. Predictive and prognostic tools for NEC are essential to advance our biological insight with a view towards non-invasive detection and accurate and timely phenotyping. We have developed a NEC Biorepository with a variety of specimen types and extensive clinical metadata obtained prospectively from premature infants before the development of NEC. These samples allow us to interrogate the mechanisms that underlie NEC development, including genetic or environmental factors. These factors include epigenetic mechanisms that regulate important aspects of cellular differentiation and gut development. Importantly, the epigenetic mechanisms, specifically, at the level of DNA methylation that take place during neonatal NEC are unknown. Our preliminary epigenomic data demonstrate that numerous biological pathways are altered during NEC. Based on these findings, we now hypothesize that non-invasive identification of methylation signatures can identify an infant at risk for necrotizing enterocolitis. We will test this hypothesis by defining and quantifying the DNA methylation signatures in stool and blood of premature infants before, during and after the development of NEC. Moreover, we will expand on our observations that dysregulation of multiple key pathways is a defining pathogenic feature of NEC and use our mouse model to gain additional mechanistic insights into NEC pathobiology. By the conclusion of the proposal, we will have generated a considerable amount of genomic data from infants across the time course of development and manifestation of NEC, and also during the normal extrauterine development of preterm infants. These studies will advance our understanding of the epigenomic regulation of the pathways involved during NEC development, and furthermore, may explain the unique susceptibility of the premature infant to NEC and identify a non-invasive approach to diagnosing this devastating disease.