Role of Obesity in Infection

说明(由申请人提供)：这是针对通知编号(NOT-OD-09-058)和通知标题的有效父申请RO1 DE15989：“肥胖在感染中的作用”的竞争性修订。肥胖症影响着超过10亿成年人和1760万5岁以下儿童。众所周知，肥胖会导致对感染的先天免疫反应失调。虽然这种免疫/炎症-代谢联系的分子机制尚不清楚，但最近的研究已将肥胖与牙周病联系起来，牙周病是一种与牙龈卟啉单胞菌(P.G)相关的常见传染病，其特征是牙周组织的炎症和破坏。我们自己的数据显示，喂食高脂饮食的小鼠对P.G感染诱导了缺陷的促炎细胞因子反应。在这次为期两年的修订中，我们将扩大家长AIMS P-Aim 2b和P-Aim 2c的范围，并增聘2名研究生，以加快发现的速度。具体地说，我们将确定一组在小鼠骨髓巨噬细胞(BMM)细胞对感染的反应中至关重要的基因，并将设计这些基因的修饰，使肥胖(OB)细胞对感染的反应接近于瘦(LN)细胞的反应。对感染的反应将通过五个基因的表达水平来量化，即肿瘤坏死因子、白介素6、诱导型一氧化氮合酶、白介素10和白介素1。根据亲本Aim P-Aim 2b，我们将专注于一个特定的TLR2信号通路，它被认为在细菌感染的反应中发挥核心作用。根据母公司P-Aim 2c的说法，代谢研究的重点将是FFA的影响。我们将在体外测试该设计在小鼠骨髓基质细胞中的效率。因此，本次修订提出了以下四个具体目标：目标1：构建TLR2基因网络的数学模型；目标2：构建小鼠骨髓基质细胞代谢模型；目标3：设计影响OB细胞对感染反应的遗传修饰；目标4：体外测试小鼠细胞系的遗传修饰。上面列出的四个具体目标将导致整个项目范围的显著增加。通过将最先进的计算方法与实验试验相结合，我们将能够预测OB和LN细胞之间表型差异的原因，并仅在实验中尝试通过我们的计算机测试的基因。这与亲本目标P-Aim 2b的初始范围形成了鲜明对比，后者旨在识别差异表达的基因，然后通过实验直接测试它们的扰动效果。通过包括代谢分析，我们将能够更好地了解营养对感染反应的影响，并将营养与基因表达反应联系起来。特别是，我们将量化FFA的影响，正如最初在母目标P-Aim 2c中提出的那样。在这项为期两年的修订结束时，我们将在我们的牙周动物模型中测试我们的候选者的有效性，希望转移到人类临床试验。 公共卫生相关性：这一竞争性修订项目将测试这一假设，即饮食诱导的肥胖改变肥胖动物对牙龈卟啉单胞菌的免疫反应，以回应通知编号NOT-OD-09-058。这两年补充的结果应该提供新的和关键的数据，将加深我们对饮食诱导宿主对病原体的先天性免疫反应的调节所涉及的特定途径的机制的理解。从拟议的研究中获得的新知识可能会对旨在减少肥胖相关临床后遗症的新疗法和模式的设计产生深远的影响。

DESCRIPTION (provided by applicant): This is a competitive revision to the active parent application RO1 DE15989: "Role of Obesity in Infection" in response to Notice Number (NOT-OD-09-058) and Notice Title: NIH Announces the Availability of Recovery Act Funds for Competitive Revision Applications. Obesity affects over 1 billion adults and 17.6 million children under 5 years of age. Obesity is known to result in a dysregulation of the innate immune response to infection. While the molecular mechanism that underlies this immune/inflammatory-metabolic linkage is not well understood recent studies have linked obesity to periodontal disease, a common infectious disease associated with the bacterium Porphyromonas gingivalis (P.g), and characterized by inflammation and destruction of periodontal tissues. Our own data shows that feeding mice a high fat diet induces defective proinflammatory cytokine response to P.g infection. In this two-year revision, we will extend the scope of the parent aims P- Aim 2b and P-Aim 2c and hire 2 more graduate students to accelerate the tempo of discovery . Specifically, we will identify a set of genes that are essential in the response to infection in mouse bone marrow macrophage (BMM) cells and will design modifications of these genes that will bring the response to infection of obese (OB) cells close to the response of lean (LN) cells. The response to infection will be quantified by the expression levels of five genes TNF, IL-6, iNOS, IL-10, and IL-1. According to the parent aim P-Aim 2b, we will focus on a specific TLR2 signaling pathway, which is thought to play a central role in the response to bacterial infection. The focus of the metabolic study will be on the effect of FFA, according to parent P-Aim 2c. We will test the efficiency of the design in vitro in murine BMM. This revision proposes therefore the following four specific aims: Aim 1: Construction of a mathematical model for the TLR2 gene network; Aim 2: Construction of a mouse BMM metabolic model; Aim 3: Design of genetic modifications affecting the response to infection in OB cells; Aim 4: In vitro testing of genetic modifications in mouse cell lines. The four specific aims listed above will lead to a significant increase in the scope of the overall project. By combining state-of-art computational approaches with experimental trials, we will be able to predict the cause of the phenotypic differences between the OB and LN cells, and try experimentally only genes that pass our in silico tests. This is in contrast with the initial scope of the parent aim P-Aim 2b, which was to identify genes that are differentially expressed and then directly test the effect of their perturbations experimentally. By including metabolic analysis, we will be able to better understand the effect of nutrition on the response to infection, and link nutrition to the gene expression response. In particular, we will quantify the effect of FFA, as initially proposed in the parent aim P-Aim 2c. At the end of this two-year revision, we will be in position of testing efficacy of our candidates in our periodontal animal model in hopes of moving to human clinical trials. PUBLIC HEALTH RELEVANCE: This competitive revision project will test the hypothesis that diet-induced obesity alters the immune response to Porphyromonas gingivalis in obese animals in response to Notice Number NOT-OD-09-058. The results of these 2 year supplement should provide novel and crucial data that will deepen our understanding of the pathway- specific mechanisms involved in the diet-induced regulation of host innate immune response to pathogens. New knowledge gained from the proposed studies will likely have profound implications for the design of new therapies and modalities aimed at reducing clinical sequelae associated with obesity.