Point-of-care immunoassay panel for cardiotonic steroids

描述（由申请人提供）：子痫前期（PE）是一种严重的妊娠并发症，表现为高血压、蛋白尿和水肿，有时伴有脑病、癫痫发作和肝功能衰竭。妊娠并发症发生率为5%至10%，是全世界孕产妇和胎儿发病率和死亡率的主要原因。内源性“地高辛样”因子（EDLF）的循环水平升高，这是一种与抗地高辛抗体交叉反应并抑制NA+/K+ atp酶（NKA）的未知物质，于20世纪80年代首次被发现。大量文献支持EDLF水平升高可能是高血压发病的致病因素的假说。最近，马里诺bufagenin (MBG)，一种内源性强心性类固醇（CTS）被确定为EDLF。妊娠合并PE时，血浆MBG升高5倍以上，提示其有一定的病理生理作用。Digibind是一种与MBG交叉反应的抗地高辛抗血清，在51例严重PE患者中，与安慰剂相比，Digibind显著改善了肾功能，无不良反应。针对MBG的单克隆抗体正处于PE的临床试验中。缺乏商业上可用的检测方法严重阻碍了对MBG和至少两种其他促心类固醇在PE和其他疾病中的作用的研究。这个项目的总体目标是发展

DESCRIPTION (provided by applicant): Preeclampsia (PE) is a serious complication of pregnancy manifested by high blood pressure, proteinuria, and edema, sometimes with encephalopathy, seizures, and hepatic failure. PE complicates from 5 to 10% of pregnancies, and is a major cause of maternal a fetal morbidity and mortality worldwide. Elevation in the circulating level of an endogenous "digoxin-like" factor (EDLF), an unknown substance that cross reacts with anti-digoxin antibodies and inhibits the NA+/K+ ATPase (NKA) was first noted in the 1980s. An extensive literature supports the hypothesis that increased levels of EDLF may be causative factor in the pathogenesis of hypertension. Recently, marinobufagenin (MBG), an endogenous cardiotonic steroid (CTS), has been identified as the EDLF. Plasma MBG is elevated over five-fold in pregnancies complicated by PE, suggesting a role pathophysiological role. Digibind, an anti-digoxin antiserum that cross-reacts MBG, provided significant in improvement in renal function relative to placebo among 51 patients with severe PE, with no adverse effects. Monoclonal antibodies to MBG are in clinical trials for PE. The lack of commercially available assays severely hampers research on the role MBG and at least two other cardiotonic steroids in PE and other diseases. The overall goal of this project is to develop an immunoassay panel for MBG and other potentially important endogenous cardiotonic steroids as a research tool and, ultimately, a clinical diagnostic for MBG levels in plasma and urine. In Phase I, we will identify monoclonal antibodies specific for each cardiotonic steroid demonstrating sensitivity and specificity. We will configure a competitive ELISA and will optimize it for the quantitation each CTS in plasma and urine. Finally, we will translate our competitive ELISA to a novel, automated immunoassay platform with ultrasensitive electrochemical detection. Phase II work will obtain data necessary for the submission of a 510k to support future commercialization.