Genetic Regulation, Tubular Processing and Clinical Relevance of Collecting Duct alpha-Defensins 1-3

集合管 α-防御素 1-3 的遗传调控、管状加工和临床相关性

• 批准号: 9906213
• 负责人: Douglas Brock Cines
• 金额: $ 58.68万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-06-01 至 2022-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9906213
• 关键词: Address; Adult; Affect; Anti-Bacterial Agents; Antibiotic Prophylaxis; Antibiotics; Automobile Driving; Back; Biological; Biological Assay; Bone Marrow Transplantation; Cell physiology; Child; Chronic Kidney Failure; Copy Number Polymorphism; DNA; DNA copy number; Data; Defensins; Disease; Duct (organ) structure; Ductal Epithelial Cell; End stage renal failure; Epithelial Cells; Exposure to; Gene Dosage; Genes; Genetic; Health; Host Defense; Human; Hypertension; Image; Immune; Immune system; In Vitro; Individual; Infection; Integration Host Factors; Intercalated Cell; Intercalated Duct; Invaded; Kidney; Kidney Diseases; Kidney Transplantation; Knowledge; Lead; Leukocytes; Messenger RNA; Microbe; Molecular; Mus; Organ; Pathology; Patient Care; Patients; Play; Predisposition; Process; Production; Prophylactic treatment; Proteins; Proteomics; Publications; Pyelonephritis; Radiation; Recurrence; Reflux; Regulation; Reporting; Research; Risk; Risk stratification; Role; Secondary to; Source; Techniques; Transplantation; Tubular formation; Urinary tract; Urinary tract infection; Urine; Uropathogen; Variant; Vesico-Ureteral Reflux; alpha-Defensins; antimicrobial; antimicrobial peptide; base; bench to bedside; clinically relevant; experience; gene product; human neutrophil peptide 1; humanized mouse; improved; infection risk; insight; kidney infection; mouse model; neutrophil; new therapeutic target; pathogen; personalized medicine; prevent; renal scarring; response; synergism; targeted treatment

PROJECT SUMMARY/ABSTRACT Vesicoureteral reflux affects 1-2% of all children and up to one third of these patients will experience urinary tract infections (UTI). The kidney and specifically the collect duct play a critical role in the innate defense of the kidney and urinary tract. Our group has demonstrated that intercalated cells are the primary source of a wide spectrum of innate immune antimicrobial peptides. DEFA1A3 (α-defensin 1-3) and its antimicrobial protein (AMP) product, human neutrophil protein 1-3 (HNP1-3), is important in the innate immune defense of the human kidney. Just this year we have reported that a) variations in the number of DEFA1A3 DNA copies correlate with UTI susceptibility and antibiotic response in children with vesicoureteral reflux and UTIs, b) DEFA1A3 mRNA and protein product, HNP1-3 expression is not limited to leukocytes, but also present in renal collecting duct epithelial cells and c) urine HNP1-3 increase during UTIs. Our aforementioned findings correlate with the known function of HNP1-3 as an AMP that rapidly destroys microbes. These finding are important because management of VUR and UTIs is complicated by the current inability to personalize treatment according to individual risk. For instance if all patients are treated under the assumption of recurrent pyelonephritis risk, children will be exposed to unnecessary imaging related radiation and antibiotic prophylaxis to prevent UTIs. Conversely if all patients are treated conservatively, a subset will develop potentially preventable renal scarring and chronic kidney disease. Further, identification of DEFA1A3 expressed in renal collecting duct cells, raises the possibility that renal DEFA1A3 expression could be targeted for therapeutics. Because DEFA1A3 DNA copy number variation is associated with UTI and the recent discovery that renal collecting duct cells express HNP1-3, determining HNP1-3’s role in the kidney represents clinically relevant research direction. Based on prior publications and preliminary studies, we hypothesize that renal- and neutrophil-derived DEFA1A3/HNP1-3 have distinct roles in cellular physiology/ pathology and are affected by DNA copy number variations. To this end, we will identify the unique molecular mechanisms critical to storage, secretion and activation of renally- derived alpha defensins in humans and murine UTI (Aim 1). We will utilize proteomic techniques using a mouse model of bone marrow transplantation and urine in children with UTI. In Aim 2, we will use a murine model of kidney transplantation of a humanized mouse for alpha-defensins to examine the kidney’s role in innate defense against uropathogens. In Aim 3, we will utilize this murine model and in vitro studies to dissect the role of DNA copy number variations in the DEFA1A3 locus in UTI susceptibility and antibiotic synergy.

项目摘要/摘要 膀胱输尿管反流影响1-2%的儿童，其中多达三分之一的患者将经历尿路 感染(UTI)。肾脏，特别是集合管，在肾脏的天然防御和 尿路。我们的研究小组已经证明，间质细胞是一系列先天激素的主要来源。 免疫抗菌肽。DEFA1A3(α-防御素1-3)及其抗菌蛋白产物，人 中性粒细胞蛋白1-3(HNP1-3)在人类肾脏的天然免疫防御中起重要作用。就在今年，我们有 据报道，a)DEFA1A3DNA拷贝数的变化与尿路感染的敏感性和抗生素有关 膀胱输尿管反流和尿路感染患儿的反应，b)DEFA1A3mRNA和蛋白产物，HNP1-3的表达 不限于白细胞，也存在于肾集合管上皮细胞和c)尿HNP1-3在 UTIS。我们的上述发现与HNP1-3作为AMP的已知功能相关，AMP可以迅速破坏 微生物。这些发现很重要，因为VUR和UTI的管理因目前无法 根据个体风险进行个性化治疗。例如，如果所有患者都在假设复发的情况下接受治疗 肾盂肾炎的风险，儿童会暴露在不必要的影像相关辐射和抗生素预防 预防尿路感染。相反，如果所有患者都接受保守治疗，一部分患者将发展为潜在的可预防的肾脏。 结疤和慢性肾脏疾病。此外，鉴定在肾脏集合管细胞中表达的DEFA1A3，提高了 肾脏DEFA1A3表达可作为治疗靶点的可能性。因为DEFA1A3 DNA拷贝数 变异与尿路感染和最近发现的肾脏集合管细胞表达HNP1-3有关，确定 HNP1-3‘S在肾脏中的作用代表了临床相关研究方向。基于之前的出版物和初步的 研究认为，肾脏和中性粒细胞来源的DEFA1A3/HNP1-3在细胞生理学中有不同的作用。 并受DNA拷贝数变异的影响。 为此，我们将确定对肾素的储存、分泌和激活至关重要的独特的分子机制。 人类和小鼠尿路感染中衍生的阿尔法防御素(目标1)。我们将利用蛋白质组学技术使用小鼠模型 尿路感染患儿的骨髓移植和尿液分析。在目标2中，我们将使用小鼠肾脏模型 移植人源化小鼠的α-防御素来研究肾脏在先天性防御中的作用 泌尿系病原体。在目标3中，我们将利用这个小鼠模型和体外研究来剖析dna拷贝数的作用。 尿路感染敏感性和抗生素协同作用中DEFA1A3基因的变异。