Molecular Signatures of Early-Onset Neonatal Sepsis in Umbilical Cord Blood

项目总结 侵袭性细菌感染引起的早发性脓毒症(EOS)是婴儿和儿童发病率的主要原因 对早产儿的影响不成比例。对EOS的准确诊断仍然是不够的。低谷 对培养结果的敏感性和延迟时间，以及现有实验室的糟糕预测价值 标记物导致我们无法排除EOS。因此，婴儿暴露在长时间的广谱环境中。 经验性抗生素，具有严重的相关不良后果，如坏死性小肠结肠炎， 抗生素耐药感染和改变的微生物群。这项拟议的研究将应用蛋白质组学来识别 胎龄特异性脐带血标志物的开发 对EOS的强烈负面风险预测。脐带血很有希望识别EOS，因为它反映了子宫内的 感染源自早产的环境。在之前的工作中，我们发现炎性蛋白 早产儿脐血中淀粉样蛋白A、C反应蛋白和结合珠蛋白显著升高 具有文化确认的EOS。这些数据告诉我们的假设，脐带血蛋白的组合提供了 区分即将到来的EOS和未感染状态的签名。存档的脐带血来自现有的 纵向队列将在嵌套病例对照设计中使用。目标1将测量脐带血蛋白质组 使用非靶向蛋白质组学方法研究不同孕期未感染婴儿(对照)的特征 发育谱。目标2(A)然后将确定婴儿的脐带血蛋白质组特征 确诊的EOS(CEO)和培养阴性的假定脓毒症(PS)。首席执行官将被比作配对的控制者 鉴定差异表达的蛋白质和候选标记。PS蛋白质组将被分析以帮助 描述这个异质性组的真实感染和炎症性亚型。生物信息学途径 分析可能为胎儿免疫反应提供新的见解。目标2(B)将确定最佳组合 通过对蛋白质组学数据的机器学习决策分析来排除EOS的标记。配对胎盘 AIM 2(C)中的蛋白质组学将探索胎儿炎症的起源。目标3(A)将通过一种 正交免疫测定法。在新受试者的验证集合中，目标3(B)将测量候选分数 通过靶向蛋白质组学和测试应用所提出的诊断工具。用正式的教学方法和一个 西北大学的导师团队，在早产、败血症、生物标记物发现、 生物统计学和决策建模，由Patrick Seed医学博士领导，候选人将获得高级翻译 在围产期研究研究设计、高级免疫学、蛋白质组学和 生物信息学来推进她的研究议程。拟议的研究和职业发展将是 实现候选人职业目标的基础：1)领导临床-翻译研究计划 围产期感染的病理生理和宿主反应2)带来新的、可靠的脓毒症诊断方法 到临床实践，通过EOS的靶向治疗和抗生素的管理来改善新生儿的结局。

PROJECT SUMMARY Early-onset sepsis (EOS) due to invasive bacterial infection is a leading cause of morbidity in infants and disproportionately affects those born preterm. Accurate diagnosis of EOS remains inadequate. The low sensitivity and delayed time to culture results combined with the poor predictive values of available laboratory markers leads to our inability to rule-out EOS. Thus, infants are exposed to extended duration broad-spectrum empiric antibiotics, which have serious associated adverse consequences such as necrotizing enterocolitis, antibiotic resistant infections, and an altered microbiome. The proposed research will apply proteomics to identify gestational age-specific umbilical cord blood markers toward development of a proposed diagnostic tool with strong negative risk prediction for EOS. Cord blood is promising to identify EOS as it reflects the intrauterine environment where infection originates in preterm birth. In previous work, we found that inflammatory proteins serum amyloid A, C-reactive protein and haptoglobin are substantially elevated in cord blood of preterm infants with culture-confirmed EOS. These data inform our hypothesis that a combination of cord blood proteins provides a signature to differentiate impending EOS and uninfected states. Archived cord blood from infants in an existing longitudinal cohort will be used in a nested case-control design. Aim 1 will measure the cord blood proteome of uninfected infants (controls) across gestational ages using an untargeted proteomics approach to characterize the developmental spectrum. Aim 2(a) will then determine the cord blood proteome signatures of infants with confirmed EOS (cEOS) and culture-negative presumed sepsis (PS). cEOS will be compared to matched controls to identify differentially expressed proteins and candidate markers. PS proteomes will be analyzed to help delineate true infection versus inflammatory subtypes in this heterogeneous group. Bioinformatics pathway analysis may provide novel insights into fetal immune response. Aim 2(b) will determine the best combination of markers to exclude EOS through machine learning decision analysis of proteomics data. Paired placental proteomics in Aim 2(c) will explore origins of fetal inflammation. Aim 3(a) will quantify candidate proteins by an orthogonal immunoassay method. In a validation set of new subjects, Aim 3(b) will measure candidate markers by targeted proteomics and test application of the proposed diagnostic tool. With formal didactics and a mentorship team at Northwestern University with expertise in prematurity, sepsis, biomarker discovery, biostatistics, and decision modeling led by Patrick Seed MD Ph.D., the candidate will gain advanced translational research experience and skills in perinatal research study design, advanced immunology, proteomics, and bioinformatics to further her research agenda. The proposed research and career development will be fundamental towards achieving the candidate’s career goals to: 1) lead a clinical-translational research program on the pathophysiology and host responses of perinatal infection and 2) bring new, reliable sepsis diagnostics to clinical practice, to improve neonatal outcomes through targeted treatment of EOS and antibiotic stewardship.