Novel diagnostic and safety biomarkers of liver injury and hepatotoxicity

描述（由申请人提供）：在美国和世界范围内，由各种形式的肝损伤引起的肝损伤和衰竭是总体发病率和死亡率的重要来源。持续性肝损伤发生在病毒性肝炎、脂肪性肝病（脂肪性肝炎）、药物或酒精和自身免疫性肝炎。在许多临床情况下，肝损伤是由复杂创伤引起的多器官功能衰竭的重要组成部分，包括爆炸伤、感染性休克和肝移植后移植物衰竭，往往导致患者死亡。广泛用于“肝功能”检测的血清ALT和AST酶测定既不敏感，也不具有肝脏特异性，不能评估肝损伤的程度或预测结果。如果肝损伤迫在眉睫，组织活检通常用于诊断。这表明临床明确需要非侵入性生物标志物来早期检测肝损伤并增强诊断信息。在此，我们建议继续开发新的肝脏特异性生物标志物，这些标志物易于在血清中检测到，可用于肝损伤患者的早期诊断，并有助于监测患者在药物治疗期间的潜在肝毒性。我们的生物标志物也可用于肝毒性的临床前研究。我们在大鼠肝损伤模型中发现了几种新的肝脏特异性生物标志物，其中精氨酸琥珀酸合成酶（ASS）和肝雌激素硫转移酶（EST-1）是最敏感的标志物，它们在血液中迅速积累，并与损伤的严重程度相关。在第一阶段，我们开发了一种用于定量血清中ASS的SW ELISA原型，并获得了足够的数据，证明与ALT/AST相比，在肝损伤实验模型中具有更高的生物标志物敏感性和特异性。此外，我们提供了概念验证数据，表明血清ASS在几种肝脏疾病和肝损伤患者中的诊断和预后价值。在II期，将开发用于ASS和EST-1的即用型elisa试剂盒，并在肝损伤和肝毒性大鼠模型的临床前研究中进行验证。将在保证质量的条件下生产充足的检测成分（如抗体和抗原）。我们将描述ASS和EST-1检测在不同类型肝脏疾病和肝损伤患者中的诊断潜力。生物标志物水平将与临床数据相关，包括肝活检、血清学和实验室数据，重点是肝损伤严重程度、疾病进展和结果。评估ASS/EST-1的准确性、敏感性、特异性和诊断/预后价值，并与ALT/AST进行比较。这些分析将用于支持向FDA提交ide前申请，以验证这些检测作为诊断工具并进一步商业化。该二期项目的成果将包括两种肝损伤生物标志物的ELISA检测，以及支持这些生物标志物作为肝损伤诊断工具和监测肝毒性程度的临床数据，这些数据远远超出了ALT/AST测量所获得的信息。

DESCRIPTION (provided by applicant): Liver damage and failure due to various forms of hepatic injury is a significant source of overall morbidity and mortality in the US and worldwide. Persistent hepatic injury occurs during viral hepatitis, fatty liver disease (steatohepatitis), drug or alcohol and autoimmune induced hepatitis. Clinical conditions are numerous where hepatic injury is a vital component of multi-organ failure caused by complex trauma including blast injury, septic shock, and graft failure after liver transplantation often leading to death of the patient. Enzymatic assays of serum ALT and AST, widely used as part of a `hepatic function' panel, are neither sensitive nor particularity specific to the liver and do not assess the magnitude of liver injury or predict outcome. If liver damage is imminent, tissue biopsies are routinely used for diagnosis. This indicates an explicit clinical need for non-invasive biomarkers for early detection of liver injury with enhanced diagnostic information. We propose here the continuation of the development of novel liver specific biomarkers which are easily detected in serum and can be used for early diagnosis of patients with liver injury and aid in monitoring of potential liver toxicity in patients during drug treatment. Our biomarkers can also be used in preclinical studies of hepatotoxicity. We identified several novel liver-specific biomarkers in rat models of hepatic injury with the argininosuccinate synthase (ASS) and hepatic estrogen sulfotransferases (EST-1) being the most sensitive markers which rapidly accumulated in blood and correlated with the severity of damage. In Phase I, a prototype SW ELISA for quantifying ASS in serum was developed, and sufficient data were obtained demonstrating the greater biomarker sensitivity and specificity in experimental models of liver injury compared to ALT/AST. Also, we provided the proof-of-concept data indicating the diagnostic and prognostic value of serum ASS in human patients with several types of liver diseases and hepatic injury. In Phase II, a ready-to-use ELISAs Kits for ASS and EST-1 will be developed and validated in preclinical studies in rat models of liver injury and hepatotoxicity. Sufficient supplies of the assay components (e.g. antibodies and antigens) will be produced under quality assured conditions. We will characterize the diagnostic potential of ASS and EST-1 assays in human patients with various types of liver diseases and hepatic injury. The biomarker levels will be that will be correlated with clinical data including liver biopsy, serological and laboratory data with an emphasis on hepatic injury severity, disease progression and outcome. The accuracy, sensitivity, specificity and diagnostic/prognostic values of ASS/EST-1 will be assessed and compared with ALT/AST. These analyses will be used to support a pre-IDE application to the FDA for validation of these assays as diagnostic tools and further commercialization. The deliverables of this Phase II project will be quality assured ELISA assays for two liver injury biomarkers, and clinical data supporting the use of the biomarkers as tools for aid in the diagnosis of liver injury and monitor the magnitude of liver toxicity far beyond information obtained from ALT/AST measurements. PUBLIC HEALTH RELEVANCE: Liver health is a major component of human wellbeing. Many environmental chemicals, pathogens, drugs or excessive alcohol can harm the liver and affect its function. An estimated 5.5 million Americans have chronic liver diseases, including viral hepatitis, alcoholic liver disease or hepatic cancer, which frequently lead to liver failure and requires liver transplantation. Moreover, increasing numbers of prescription drugs such as cholesterol-lowering drugs and over-the-counter medications, including acetaminophen, can potentially cause liver toxicity and, thereby, require medical liver function checks. For the last 30 years, two enzymes, serum ALT and AST have been used in hepatic function panels to assess liver health. However, ALT/AST are neither sensitive nor specific to detect mild injure, assess magnitude of damage or predict outcome. Banyan Biomarkers is developing predictive bioassays such as ASS and EST-1 that can help determine liver insults early on in patients that suffer from liver toxicity from therapeutic drugs or environmental toxins. These assays will provide a novel diagnostic/prognostic tools and serve as "safety biomarkers." according to the FDA.