FEASIBILITY OF REPAIRING GBM DEFECTS IN VIVO

体内修复 GBM 缺陷的可行性

• 批准号: 8385717
• 负责人: JEFFREY H MINER
• 金额: $ 22.8万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-17 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8385717
• 关键词: Accounting; Affect; Agrin; Albuminuria; Basement membrane; Binding; Biological Models; Blood capillaries; Bone Marrow; Bowman' s space; Cell Therapy; Cell Transplants; Cells; Collagen; Collagen Type IV; Congenital Nephrotic Syndrome; Defect; Development; Diabetic Nephropathy; Disease; Disease model; Doxycycline; Endothelial Cells; Endothelium; Experimental Designs; Extracellular Matrix; Extravasation; Feasibility Studies; Figs - dietary; Foot Process; Gene Proteins; Glomerulonephritis; Goals; Hematuria; Heparan Sulfate Proteoglycan; Hereditary nephritis; Human; Individual; Infusion procedures; Inherited; Kidney; Kidney Diseases; Knowledge; Laminin; Membrane Biology; Membrane Proteins; Mus; Mutation; Nature; Nephrotic Syndrome; Pathology; Patients; Plasma Proteins; Procedures; Protein Isoforms; Proteinuria; Renal function; Renal glomerular disease; Reporting; Research; Sagittaria; Sorting - Cell Movement; Syndrome; Testing; Tetracyclines; Time; Trans-Activators; Transgenes; Transgenic Mice; Translating; Urine; base; capillary; design; enzyme replacement therapy; glomerular basement membrane; glomerular filtration; heparin proteoglycan; human disease; improved; in vivo; laminin S; mesangial cell; mouse genome; mouse model; mutant; nidogen-1; podocyte; prevent; programs; repaired; research study; restoration; slit diaphragm; tool

DESCRIPTION (provided by applicant): The glomerular basement membrane (GBM) is a specialized extracellular matrix and a crucial component of the kidney's glomerular filtration barrier (GFB) between the vasculature and the urinary space. The GBM is initially co-synthesized by, and lies between, the podocytes and the glomerular endothelial cells, and it is bound by mesangial cells at the base of each capillary loop. The GBM's major components are laminin-521 (alpha5beta2gamma1), type IV collagen (the alpha3/4/5 network), nidogens-1 and -2, and the heparin sulfate proteoglycan agrin. Of these 9 components, mutations that affect 4 of them cause human kidney disease: mutations that affect the collagen IV chains cause Alport syndrome (hereditary glomerulonephritis), and those that affect laminin beta2 (LAMB2) cause Pierson syndrome/congenital nephrotic syndrome. The well-defined nature of the glomerular defects and the existence of well- characterized mouse models make these diseases especially attractive for targeted therapy. Several groups have already explored the potential for cell-based therapies aimed at replacing the missing collagen IV network in Alport mice. Although the positive effects of bone marrow and other cell transplants or infusions on progression of kidney disease seem promising, the reported effects of these procedures on the GBM's collagen IV network have been disparate and controversial. Here we propose experiments aimed at directly testing the feasibility of altering the GBM after it has matured in mouse models of Alport syndrome and Pierson syndrome/congenital nephrotic syndrome, with the goal of replacing the abnormal networks present in the mutants with the networks normally present in healthy mature glomeruli. We will use newly generated podocyte-specific reverse tetracycline transactivator transgenic mice and existing collagen IV and laminin mutant and transgenic mice to attempt to induce network restoration after GBM maturation. The results of these feasibility studies will have implications not only for treating human kidney disease, but also for our basic understanding of basement membrane biology, GBM plasticity, and cell/matrix interactions! PUBLIC HEALTH RELEVANCE: The glomerular basement membrane (GBM) is an important component of the glomerular filtration barrier that prevents the leakage of plasma proteins into the urine. Some patients with kidney disease have abnormal GBM composition. The overall goal of this proposal is to use a mouse model system to investigate whether an abnormal GBM composition can be normalized in patients and whether this will improve and/or prolong kidney function.

描述(申请人提供)：肾小球基底膜(GBM)是一种特殊的细胞外基质，是肾脏血管和尿腔之间的肾小球滤过屏障(GFB)的重要组成部分。GBM最初由足细胞和肾小球内皮细胞共同合成，位于足细胞和肾小球内皮细胞之间，并与每个毛细血管环底部的系膜细胞结合。GBM的主要成分是层粘连蛋白-521(Alpha5β2 Gamma1)、IV型胶原(Alpha3/4/5网络)、Nidogens-1和-2，以及硫酸肝素蛋白多糖集聚蛋白。在这9种成分中，影响其中4种的突变会导致人类肾脏疾病：影响IV型胶原链的突变会导致Alport综合征(遗传性肾小球肾炎)，而影响层粘连蛋白Beta2(LAMB2)的突变会导致Pierson综合征/先天性肾病综合征。肾小球缺陷的明确性质和特征良好的小鼠模型的存在使这些疾病特别吸引靶向治疗。几个小组已经探索了基于细胞的治疗的可能性，旨在取代Alport小鼠缺失的IV型胶原网络。尽管骨髓和其他细胞移植或输注对肾脏疾病进展的积极作用似乎是有希望的，但这些程序对GBM的IV型胶原网络的报道效果一直是不同的，也存在争议。在这里，我们提出的实验旨在直接测试在Alport综合征和Pierson综合征/先天性肾病综合征的小鼠模型中改变GBM的可行性，目的是用健康成熟的肾小球中正常存在的网络来取代突变中存在的异常网络。我们将使用新产生的足细胞特异性反向四环素反式激活转基因小鼠和现有的IV型胶原和层粘连蛋白突变体和转基因小鼠，试图诱导GBM成熟后的网络恢复。这些可行性研究的结果不仅对治疗人类肾脏疾病有意义，而且对我们对基底膜生物学、基底膜可塑性和细胞/基质相互作用的基本理解也有意义！ 公共卫生相关性：肾小球基底膜(GBM)是防止血浆蛋白渗入尿液的肾小球滤过屏障的重要组成部分。部分肾脏疾病患者存在GBM成分异常。这项建议的总体目标是使用小鼠模型系统来研究患者是否可以使异常的GBM成分正常化，以及这是否会改善和/或延长肾功能。