Pathogenesis of Endotoxin-Induced Acute Renal Failure

我的最终目标是在学术环境中领导一个独立的研究实验室，以更好地了解急性肾功能衰竭（ARF）。在过去三年的肾脏学研究中，我研究了一种内毒素诱导的ARF小鼠模型，该模型是由肿瘤坏死因子（TNF）作用于肾脏中其主要受体TNFRI介导的。从临床角度来看，这一主题具有高度相关性，因为ARF是一种常见且严重的综合征，没有有效的治疗方法，并且通常是败血症的后果。在这个职业发展奖的支持下，在Richard Quigg博士的赞助下，在芝加哥大学肾脏科的指导和支持下，我希望将我的技能扩展到新的领域，如细胞生物学，以实现这一长期目标。该建议将验证内毒素诱导的ARF是由肾中性粒细胞浸润、肾细胞凋亡以及TNF对肾小管细胞的直接作用引起的其他形式的神经性或亚溶质损伤的结果。第一个具体目的是描述内毒素给药后肾脏白细胞积累的时间过程，确定介导这一过程的关键粘附分子和趋化因子，并利用抑制性抗体和基因“敲除”小鼠评估其致病作用。第二个特定目标旨在更好地表征内毒素给药后肾细胞凋亡的时间过程，并通过使用特定的药物来评估其致病作用。第三个特定目标旨在描述TNF对培养的肾近端小管细胞的影响，特别是其对细胞活力、凋亡、形态、细胞-细胞粘附和代谢的影响。本研究的第四个具体目的是描述内毒素给药后肾脏血流动力学的影响，特别是对系统血压、肾血流量和肾血管阻力的影响。希望这些科学问题的答案可以整合成一个关于内毒素如何损伤肾脏的整体范例，并且这项工作可以转化为ARF有效治疗方法的设计。

My ultimate goal is to head an idependent research laboratory in an academic setting directed towards a better understanding of acute renal failure (ARF). I have spent the last three years of my nephrology fellowship investigating a mouse model of endotoxin-induced ARF is mediated by tumor necrosis factor (TNF) acting on its principal receptor, TNFRI, in kidney. This topic is highly relevant from a clinical perspective, as ARF is a common and serious syndrome with no effective therapy, and is frequently a consequence of sepsis. With the support of this Career Development Award, and the guidance and support of the University of Chicago's Section of Nephrology under the sponsorship of Dr. Richard Quigg, I hope to expand my skills into new areas such as cell biology, to advance towards this long-term goal. This proposal will test the hypothesis that endotoxin- induced ARF is a consequence of renal neutrophil infiltration, renal cell apoptosis, and other forms of neurotic or sublytic injury by the direct action of TNF on renal tubular cells. The first specific aim seeks to characterize the time course of leukocyte accumulation in the kidney after endotoxin administration, to identify key adhesion molecules and chemokines mediating this process, and to evaluate their pathogenic role with the use of inhibitory antibodies and genetic "knockout" mice. The second specific aim seeks to better characterize the time course of renal cell apoptosis after endotoxin administration and to evaluate its pathogenic role through the use of specific pharmacologic agents. The third specific aim seeks to describe the effects of TNF on renal proximal tubular cells in culture, and specifically to access their effects on cell viability, apoptosis, morphology, cell-cell adhesion, and metabolism. The fourth specific aim of this study seeks to characterize the renal hemodynamic effects which occur after the administration of endotoxin, specifically the effects on systematic blood pressure, renal blood flow, and renal vascular resistance. It is hoped that the answers to these scientific questions can be assembled into a overall paradigm of how endotoxin injures the kidney, and that this work can be translated into the design of effective therapies for ARF.