Micro-Liver Platform Development for Evaluating Drug Disposition and Toxicity In

说明(申请人提供)：肝脏毒性是药物化合物(如瑞祖林、百忧解)上市前和上市后损耗的主要原因。器官功能因物种而异的显著差异现在需要用旨在评估人类对药物反应的分析来补充动物数据。原代人肝细胞贴壁培养被认为是评估临床前药物代谢、酶诱导和肝脏特异性毒性的金标准。然而，在常规用于药物开发的培养条件下，肝细胞表现出肝脏特异性功能的快速(几小时)下降。最近，一种稳健的人体肝组织模型已经被开发出来，该模型具有优化的微尺度结构，在行业标准的多孔格式中，在体外将肝脏特异性功能保留4-6周。这个微尺度平台中的肝细胞分泌肝脏特有的产物，展示功能性的CYP450和结合酶，向胆小管分泌分子，并维持与评估药物处置相关的肝脏特有基因的高水平表达。小型企业创新研究(SBIR)第二阶段项目的主要目标是进一步开发和优化这些微型人类肝脏培养物，并将其与小型化策略和检测技术相结合，以实现经济高效的高通量体外筛选。由于药物性肝损伤(DILI)是急性肝功能衰竭和药物高流失率的主要原因，我们将优化我们的微型人体肝脏，专门用于体外筛选特定基因型和临床相关的药物处置和偶联DILI。我们在这里开发的技术可能会在几类治疗性化合物(药物、生物制品)的开发、环境毒物的处置和伤害潜力的评估、肝脏生理和疾病的基础研究、新的生物标志物的识别以及肝病的个性化药物方面找到广泛的用途。未来，微技术与组织工程的持续结合可能会刺激其他组织模型的发展，并将它们整合到所谓的芯片上的人身上。 公共卫生相关性：该项目中提出的研究旨在开发一种用于高通量筛选(HTS)应用的微型人体肝脏微阵列，特别是用于评估药物处置和药物引起的肝损伤，这对患者、监管机构和制药/生物技术行业来说是一个严重的挑战。在未来，我们的微型微型肝脏HTS系统可能会在药物开发管道中更早地消除问题化合物，以减少患者对不安全药物的暴露。我们在这里开发的技术在评估环境毒物的伤害潜力、基础研究和肝病患者的个性化药物方面也可能有用。

DESCRIPTION (provided by applicant): Liver toxicity is the leading cause of pre-launch and post-market attrition of pharmaceutical compounds (i.e. Rezulin, Prexige). Significant species-specific differences in organ functions now necessitate supplementation of animal data with assays designed to assess human responses to drugs. Adherent cultures of primary human hepatocytes are considered to be the gold standard for evaluating preclinical drug metabolism, enzyme induction, and liver-specific toxicity. However, hepatocytes display a rapid (hours) decline in liver-specific functions under conventional culture conditions utilized routinely for drug development. Recently, a robust model of human liver tissue has been developed with optimized microscale architecture in an industry-standard multiwell format that retains liver-specific functions for 4-6 weeks in vitro. Hepatocytes in this microscale platform secrete liver-specific products, display functional CYP450 and conjugation enzymes, secrete molecules into the bile canaliculi, and maintain high levels of expression of liver-specific genes relevant for evaluating drug disposition. The primary objective of this Small Business Innovation Research (SBIR) Phase II project is to further develop and optimize these microscale human liver cultures and couple them with miniaturization strategies and assay technologies for cost-effective high-throughput in vitro screening. Since drug-induced liver injury (DILI) is a leading cause of acute liver failures and the high attrition rate of pharmaceuticals, we will optimize our miniaturized human livers specifically for the in vitro screening of genotype-specific and clinically-relevant drug disposition and coupled DILI. The technologies we develop here may find broad utility in the development of several classes of therapeutic compounds (drugs, biologics), in evaluating the disposition and injury potential of environmental toxicants, in fundamental investigations of liver physiology and disease, in the identification of new biomarkers, and in personalized medicine for liver disease. In the future, continued combination of microtechnology with tissue engineering may spur the development of other tissue models and their integration into the so-called 'human-on-a-chip'. PUBLIC HEALTH RELEVANCE: The studies proposed in this project are aimed towards developing a miniaturized human liver microarray for high-throughput screening (HTS) applications, specifically for evaluating drug disposition and drug-induced liver injury, a serious challenge for patients, regulatory agencies and the pharmaceutical/biotech industry. In the future, our miniaturized micro-liver HTS system may eliminate problematic compounds much earlier in the drug development pipeline towards reducing patient exposure to unsafe drugs. The technologies we develop here may also find utility in assessing the injury potential of environmental toxicants, in basic research, and in personalized medicine for patients with liver disease.