Hepcidin Lateral Flow Device for Prediction of Acute Kidney Injury

描述（由申请人提供）：急性肾损伤（AKI）是体外循环（CPB）辅助手术中常见的严重并发症，包括冠状动脉旁路移植术、瓣膜置换术、主动脉动脉瘤和器官移植。老年患者、糖尿病患者和慢性肾脏疾病（CKD）患者术后发生AKI的风险非常高。每年100万例CPB手术导致数千例aki相关死亡和残疾，涉及肾脏替代疗法（RRT），累计花费数十亿美元。现有的肾标志物证实AKI的功能丧失（如血清肌酐）是诊断AKI的非常晚的标志物（1-3天）。很少有生物标志物（如NGAL， KIM-1）可用于AKI的早期预测。预测cpb后AKI严重程度的早期生物标志物和快速测试将使患者分层、早期治疗干预和AKI药物开发成为可能。最近，我们发现hepcidin是一种小肽（2.78kD），在肝脏中产生并通过尿液排出，可能是cpb辅助手术后AKI的良好生物标志物。在澳大利亚（NCT00910221; Prowle et al. 2012）和德国（NCT00672334; Haase-Felietz et al. 2011）的两项100例患者临床试验中，分别在基线、距基线6小时和24小时采集血浆和尿液样本。与已建立的AKI生物标志物血浆肌酐（pCr）和中性粒细胞明胶酶相关脂钙蛋白（NGAL）相比，在这两项研究中，当采用RIFLE标准（基于pCr）评分时，尿hepcidin （uHep; ng/ml）和uHep （uHep/uCr; ng/mg）与AKI严重程度呈负相关。无aki患者在6小时时uHep和uHep/uCr水平升高，并在24小时内升高。在德国的研究中，与AKI患者相比，uHep和uHep/uCr在6小时时增加了3- 7倍（P = 0.004, P = 0.002）， AUC-ROC为0.80；预测无aki恢复的AUC-ROC分别为0.88和0.81；为0.88，预测无rrt恢复。这些数据支持uHep和uHep/uCr作为6小时无aki恢复的有希望的生物标志物，比现有的生物标志物如血浆肌酐、尿输出量和GFR要早得多。然而，要使生物标志物对AKI的诊断有用，必须对其进行测量，并将数据迅速返回给外科医生和ICU工作人员，因为AKI的临床干预措施很少。我们建议开发一种便携式、定量侧流装置（LFD），可以快速、定量地测定ICU患者的尿和血浆hepcidin浓度。我们最近在正在进行的SBIR研究中发现并鉴定了两种新的小鼠抗hepcidin单克隆抗体（MAb） （PA 08- 114; 2-R44-DK083843-02）。在我们的最后一次提交中，我们使用金共轭hepcidin示踪剂制作了hepcidin H1单抗LFD原型，我们最终放弃了。我们修订后的第一阶段研发工作的具体目标是：1)。在一项前瞻性临床研究中评估1800个去鉴定时间匹配样本中的尿和血浆hepcidin、NGAL和KIM-1，并进行广泛的统计分析。2)开发一种适用于血浆和尿hepcidin的快速、定量侧流装置（LFD），并在前瞻性研究的临床样本中测试该新装置，以评估hepcidin LFD对cpb后AKI的实用性。

DESCRIPTION (provided by applicant): Acute kidney injury (AKI) is a common, severe complication of cardiopulmonary bypass (CPB) assisted surgeries, and include coronary artery bypass grafts, valve replacements, aortic aneurisms, and organ transplants. Elderly patients, diabetics, and chronic kidney disease (CKD) patients, have very high risk of developing AKI postoperatively. One million CPB surgeries yearly result in thousands of AKI-related deaths and disabilities involving renal replacement therapy (RRT), cumulatively costing billions. Existing renal markers confirming loss of function (e.g. serum creatinine) in AKI are very late markers (1-3 days) for diagnosis of AKI. Few biomarkers (e.g. NGAL, KIM-1) are commercially available for early prediction of AKI. Early biomarkers and rapid tests predicting the severity of post-CPB AKI will enable patient stratification, earlier therapeutic interventions, and drug development for AKI Recently, we have shown that hepcidin is a small peptide (2.78kD) produced in the liver and excreted in urine and may be a good biomarker for AKI post CPB-assisted surgery. In two 100 patient clinical trials with our collaborators in Australia (NCT00910221; Prowle et al. 2012) and Germany (NCT00672334; Haase-Felietz et al. 2011), plasma and urine samples were taken at baseline, 6hr and 24hr from baseline. In contrast to established biomarkers of AKI, plasma creatinine (pCr) and neutrophil gelatinase-associated lipocalin (NGAL), in both these studies urinary hepcidin (uHep; ng/ml) and uHep adjusted for urine creatinine (uHep/uCr; ng/mg) was inversely correlated with severity of AKI when scored by RIFLE criteria (based on pCr). AKI-free patients had highly elevated levels of uHep and uHep/uCr at 6hr that increased through 24hr. uHep and uHep/uCr increased 3- to 7-fold compared to patients with AKI (P = 0.004, P = 0.002) at 6hr in the German study with a AUC-ROC 0.80; 0.88, respectively, for prediction of AKI-free recovery and an AUC-ROC 0.81; 0.88, respectively, for prediction of RRT-free recovery. These data support uHep and uHep/uCr as a promising biomarker of AKI-free recovery at 6 hours, much earlier than existing biomarkers such as plasma creatinine, urine output volume, and GFR. However, for a biomarker to be useful for diagnosis of AKI, it must be measured and the data returned to the surgeon and ICU staff quickly as there are few established clinical interventions for AKI. We propose development of a portable, quantitative lateral flow device (LFD) that can rapidly determine urine and plasma hepcidin concentrations rapidly and quantitatively in the ICU. We have recently discovered and characterized two new mouse anti-hepcidin monoclonal antibodies (MAb) in ongoing SBIR research (PA 08- 114; 2-R44-DK083843-02). For our last submission we made a prototype hepcidin H1 MAb LFD using a gold- conjugated hepcidin tracer that we ultimately abandoned. The specific aims for our revised Phase I research and development efforts are, 1). Assess urinary and plasma hepcidin, NGAL, and KIM-1 in 1800 de-identified time-matched samples from a prospective clinical study and perform extensive statistical analysis, and 2) Develop a rapid, quantitative lateral flow device (LFD) suitable for plasma and urine hepcidin and test the new device in the clinical samples from the prospective study to evaluate utility of a hepcidin LFD for post-CPB AKI.