Pathogenesis of Endotoxin-Induced Acute Renal Failure

我的最终目标是领导一个独立的研究实验室，在学术环境中更好地了解急性肾功能衰竭(ARF)。在我的肾脏学研究员的最后三年里，我一直在研究内毒素诱导的ARF小鼠模型，该模型是由作用于其在肾脏中的主要受体TNFRI的肿瘤坏死因子(TNF)介导的。这一主题与临床高度相关，因为ARF是一种常见而严重的综合征，没有有效的治疗方法，而且经常是脓毒症的后果。在这个职业发展奖的支持下，在理查德·奎格博士的赞助下，芝加哥大学肾脏学部的指导和支持下，我希望将我的技能扩展到细胞生物学等新领域，朝着这个长期目标前进。这项提议将检验这样一种假设，即内毒素诱导的ARF是由肿瘤坏死因子直接作用于肾小管细胞而导致的肾脏中性粒细胞浸润、肾细胞凋亡和其他形式的神经性或亚溶血性损伤的结果。第一个特指的目的是描述内毒素注射后白细胞在肾脏中聚集的时间过程，识别介导这一过程的关键黏附分子和趋化因子，并利用抑制性抗体和基因敲除小鼠来评估它们的致病作用。第二个具体目的是更好地刻画内毒素作用后肾细胞凋亡的时间过程，并通过使用特定的药理药物来评价其致病作用。第三个具体目的是描述肿瘤坏死因子对培养的肾小管上皮细胞的影响，特别是了解它们对细胞活力、细胞凋亡、细胞形态、细胞间黏附和代谢的影响。本研究的第四个具体目的是研究内毒素对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。人们希望这些科学问题的答案可以整合成内毒素如何损害肾脏的总体范例，并希望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.