Advanced GST Proteomics for Early Stage Organ-Specific Toxicity Screening

用于早期器官特异性毒性筛查的先进 GST 蛋白质组学

• 批准号: 8057097
• 负责人: KEVIN M PATRIE
• 金额: $ 11.77万
• 依托单位: OXFORD BIOMEDICAL RESEARCH, INC.
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-01-18 至 2011-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8057097
• 关键词: Acute; Animal Model; Animals; Antibodies; Archives; Biological; Biological Assay; Biological Markers; Blood; Cells; Characteristics; Clinical; Detection; Development; Disease; Dose; Drug or chemical Tissue Distribution; Early Diagnosis; Environmental Exposure; Enzymes; Exhibits; Exposure to; Family; Feasibility Studies; Glutathione S-Transferase; Goals; Half-Life; Hepatotoxicity; Human Development; Immunoassay; Intervention; Isoenzymes; Liquid substance; Liver; Measures; Methods; Modeling; Molecular Profiling; Monitor; Occupational Exposure; Organ; Pattern; Pharmaceutical Preparations; Pharmacologic Substance; Phase; Poison; Process; Protein Family; Protein Isoforms; Proteomics; Rattus; Reagent; Reporting; Research; Resolution; Screening procedure; Small Business Innovation Research Grant; Specificity; Specimen; Staging; Structure; Technology; Testing; Time; Tissues; Toxic effect; Toxicant exposure; Toxicity Tests; Toxicology; Toxin; Transaminases; Xenobiotics; commercial application; cross reactivity; falls; improved; meetings; member; minimally invasive; pre-clinical; prevent

DESCRIPTION (provided by applicant): Current biomarkers employed in the detection of organ toxicity are often not sensitive enough to detect the early stages of acute organ damage, i.e. at a stage when reducing or eliminating exposure to a toxin could prevent progression of organ damage or a disease process. By the time current toxicity biomarkers are detected in biological fluids there is already significant, often irreversible, damage to organs resulting from prolonged exposure to toxic compounds. For example, the level of aminotransferases (ALT and AST) in blood is a widely accepted practice for detecting liver damage. However, these current toxicity biomarkers are typically not detectable in blood at low levels of liver damage and require a relatively long exposure to a toxin before they are detected. The cytosolic glutathione transferase (GST) family of enzymes offer a more reliable alternative as a biomarker for organ damage as they exhibit many of the required characteristics, i.e. tissue specific localization, release into the blood at low levels of toxicity (high sensitivity), and a high intracellular concentration. The GST protein family is comprised of several classes (e.g. A, M, P) with some classes containing multiple isoforms. The many GST isoforms exhibit marked differences in tissue distribution. For example, GSTA1-1 and A2-2 are the predominant GST enzymes found in the liver, whereas GSTA3-3 is mainly expressed in steroidogenic tissues and GSTA4-4 is expressed in all tissues that have been examined. Therefore, measuring the level of specific GST isoforms in blood would be a valuable indicator of damage to a particular organ or tissue. However, current available antibodies for GSTs are not capable of distinguishing among the different GSTA isoforms. Assays for specific GST isoforms would enable a higher degree of resolution and sensitivity to organ damage due to xenobiotic exposure. Recent identification of several additional cytosolic GST classes (S, O and Z) provides an additional opportunity to further expand the toxicology applications of GST assays with the development of immunoassays that are specific for specific isoforms associated with specific tissues. The goal of Phase I feasibility studies is to develop (a) highly specific antibodies capable of distinguishing between three GSTA isoforms, namely GSTA1-1/2-2, GSTA3-3 and GSTA4-4 and (b) ultrasensitive immunoassays for these biomarkers. In addition, in Phase I we will (c) employ animal models to validate these assays as a reliable way to detect organ-specific toxicity. The long-term goal (Phase II) involves development of a comprehensive GST Proteomics panel for high sensitivity organ-specific toxicology testing that has significant preclinical and clinical commercial applications. PUBLIC HEALTH RELEVANCE: There is a great need for more sensitive, minimally-invasive methods to detect the early stages of toxicity to specific organs from exposure to drugs, or as the result of environmental or occupational exposure. The goal of the proposed research is to develop a set of highly specific and ultrasensitive tests to monitor the levels of a family of proteins (the glutathione transferases) in blood, and to incorporate these tests into a comprehensive panel for high sensitivity organ-specific toxicology testing that has significant preclinical and clinical commercial applications.

描述（由申请人提供）：目前用于器官毒性检测的生物标志物通常不够敏感，无法检测急性器官损伤的早期阶段，即在减少或消除毒素暴露可以防止器官损伤进展或疾病过程的阶段。当在生物体液中检测到当前的毒性生物标志物时，由于长期接触有毒化合物，已经对器官造成了重大的、往往是不可逆转的损害。例如，血液中转氨酶（ALT和AST）的水平被广泛接受用于检测肝损伤。然而，这些目前的毒性生物标志物通常在低水平肝损伤时无法在血液中检测到，并且需要相对长时间接触毒素才能检测到。胞质谷胱甘肽转移酶（GST）家族作为器官损伤的生物标志物提供了更可靠的选择，因为它们具有许多必需的特征，即组织特异性定位，以低毒性（高敏感性）和高细胞内浓度释放到血液中。GST蛋白家族由几个类别（例如A， M， P）组成，其中一些类别含有多个同种异构体。许多GST同种异构体在组织分布上表现出明显的差异。例如，GSTA1-1和A2-2是肝脏中发现的主要GST酶，而GSTA3-3主要表达于类固醇组织，而GSTA4-4在所有已检测的组织中都表达。因此，测量血液中特定GST同种异构体的水平将是对特定器官或组织损伤的有价值的指标。然而，目前可用的gst抗体不能区分不同的GSTA亚型。对特定的GST同种异构体进行检测，可以提高对因外源性接触而造成的器官损伤的分辨率和灵敏度。最近发现的几个额外的细胞质GST类别（S， O和Z）为进一步扩大GST分析的毒理学应用提供了额外的机会，同时开发了针对特定组织相关的特定同种异构体的免疫分析。I期可行性研究的目标是开发(a)能够区分三种GSTA亚型（即GSTA1-1/2-2、GSTA3-3和GSTA4-4）的高特异性抗体，以及(b)针对这些生物标志物的超灵敏免疫测定方法。此外，在I期，我们将(c)采用动物模型来验证这些检测作为检测器官特异性毒性的可靠方法。长期目标（II期）包括开发一个全面的GST蛋白质组学面板，用于高灵敏度器官特异性毒理学测试，具有重要的临床前和临床商业应用。