Vaidya Vishal S, Ramirez Victoria, Ichimura Takaharu, Bobadilla Norma A, Bonventre Joseph V
Renal Division, Brigham and Women's Hospital, Harvard Medical School, 4 Blackfan Circle, Harvard Institutes of Medicine, Rm. 550, Boston, MA 02115, USA.
Am J Physiol Renal Physiol. 2006 Feb;290(2):F517-29. doi: 10.1152/ajprenal.00291.2005. Epub 2005 Sep 20.
Sensitive and specific biomarkers are needed to detect early kidney injury. The objective of the present work was to develop a sensitive quantitative urinary test to identify renal injury in the rodent to facilitate early assessment of pathophysiological influences and drug toxicity. Two mouse monoclonal antibodies were made against the purified ectodomain of kidney injury molecule-1 (Kim-1), and these were used to construct a sandwich Kim-1 ELISA. The assay range of this ELISA was 50 pg/ml to 5 ng/ml, with inter- and intra-assay variability of <10%. Urine samples were collected from rats treated with one of three doses of cisplatin (2.5, 5, or 7.5 mg/kg). At one day after each of the doses, there was an approximately three- to fivefold increase in the urine Kim-1 ectodomain, whereas other routinely used biomarkers measured in this study [plasma creatinine, blood urea nitrogen (BUN), urinary N-acetyl-beta-glucosaminidase (NAG), glycosuria, proteinuria] lacked the sensitivity to show any sign of renal damage at this time point. When rats were subjected to increasing periods (10, 20, 30, or 45 min) of bilateral ischemia, there was an increasing amount of urinary Kim-1 detected. After only 10 min of bilateral ischemia, Kim-1 levels on day 1 were 10-fold higher (5 ng/ml) than control levels, whereas plasma creatinine and BUN were not increased and there was no glycosuria, increased proteinuria, or increased urinary NAG levels. Thus urinary Kim-1 levels serve as a noninvasive, rapid, sensitive, reproducible, and potentially high-throughput method to detect early kidney injury in pathophysiological studies and in preclinical drug development studies for risk-benefit profiling of pharmaceutical agents.
检测早期肾损伤需要敏感且特异的生物标志物。本研究的目的是开发一种灵敏的尿液定量检测方法，以识别啮齿动物的肾损伤，便于早期评估病理生理影响和药物毒性。制备了两种针对肾损伤分子-1（Kim-1）纯化胞外域的小鼠单克隆抗体，并用于构建夹心Kim-1酶联免疫吸附测定（ELISA）。该ELISA的检测范围为50 pg/ml至5 ng/ml，批间和批内变异率<10%。从接受三种顺铂剂量（2.5、5或7.5 mg/kg）之一治疗的大鼠收集尿液样本。在每个剂量给药一天后，尿Kim-1胞外域增加了约三到五倍，而本研究中测量的其他常规使用的生物标志物[血浆肌酐、血尿素氮（BUN）、尿N-乙酰-β-葡萄糖苷酶（NAG）、糖尿、蛋白尿]在该时间点缺乏显示任何肾损伤迹象的敏感性。当大鼠经历双侧缺血的时间增加（10、20、30或45分钟）时，检测到的尿Kim-1量增加。仅双侧缺血10分钟后，第1天的Kim-1水平比对照水平高10倍（5 ng/ml），而血浆肌酐和BUN没有增加，也没有糖尿、蛋白尿增加或尿NAG水平增加。因此，尿Kim-1水平可作为一种非侵入性、快速、灵敏、可重复且可能高通量的方法，用于在病理生理研究和临床前药物开发研究中检测早期肾损伤，以对药物进行风险效益评估。
