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

项目摘要/摘要 坏死性小肠结肠炎(NEC)是早产儿的一种破坏性并发症，它突然发展并携带 发病率高，死亡率高，没有生物标记物。NEC的高死亡率 如果有一种筛查方法可以及早发现疾病，那么这种疾病很可能会被预防。预测性和 NEC的预后工具对于促进我们的生物学洞察力以期实现非侵入性至关重要 检测和准确、及时的表型鉴定。我们已经开发了一种NEC生物库，其中包含各种 样本类型和大量临床数据前瞻性地从早产儿中获得 NEC的发展。这些样本让我们能够询问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，它调节重要的 细胞分化和肠道发育的各个方面。重要的是，表观遗传机制，特别是 新生儿NEC期间发生的DNA甲基化水平尚不清楚。我们的初步表观基因组学 数据表明，在NEC过程中，许多生物通路发生了变化。基于这些发现，我们现在 假设甲基化特征的非侵入性识别可以识别有坏死性风险的婴儿 小肠结肠炎。我们将通过定义和量化粪便和粪便中的DNA甲基化特征来检验这一假设 早产儿发生NEC前、中、后的血液分析。此外，我们将扩大我们的 观察到多个关键通路的失调是NEC的一个决定性的致病特征，并使用我们的 小鼠模型，以获得对NEC病理生物学的更多机械见解。在提案结束时， 我们将从婴儿身上产生大量的基因组数据，时间跨度为 NEC的发生和表现，以及早产儿正常宫外发育。 这些研究将促进我们对NEC过程中涉及的通路的表观基因组调控的理解 发育，此外，可以解释早产儿对NEC的独特易感性，并确定 一种诊断这种毁灭性疾病的非侵入性方法。

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.