Enhanced Image Analysis of a Transparent Fish Model

描述（由申请人提供）：越来越多的人呼吁使用替代动物模型来评估对人类健康的风险。透明水母是一种独特的动物模型，我们相信它在评估此类风险方面具有巨大的潜力。这种动物模型在胚胎、幼年和成年阶段都是透明的，通过活体动物的体壁可以看到主要的内脏器官。有了透明的medaka，目前在胚胎发生期间的现有替代模型中可以轻松地进行表型分析，现在可以扩展到生命后期。分子、细胞、组织和器官/系统水平的结构和功能变化可以无创成像，从而大大增强了整个生命的表型特征。提出了四个具体目标：1)定义medaka肝脏的生长发育，强调肝小管与微血管的关系。2)肝小管内肝细胞与胆道上皮细胞相互作用形成胆汁。3)构建细胞类型特异性转基因透明medaka，扩展肝脏发育/重塑和生长的无创检测。4)通过暴露于一种已知针对肝内胆道功能的参考肝毒素，以及在不同个体中暴露于一种已知的致癌物，导致medaka肝脏退行性和肿瘤性病变，在透明medaka幼虫中产生经证实的肝损伤。medaka的压缩生命周期，再加上它的透明特性，使得这个模型特别适合于研究胚胎后发育、衰老、毒性、诱变和致癌。特别重要的是一个模型，用于评估早期生活阶段暴露的表现，其中最初的分子紊乱可能与成年功能障碍分开很长一段时间。拟议研究的努力将集中在扩展肝脏发育/重塑和生长的无创检测过程上。我们之所以选择研究肝脏，是因为我们对这个器官系统有广泛的了解，而且它在营养物质和其他内源性分子的摄取、代谢、储存和再分配、异种生物的代谢以及胆汁的形成和排泄方面都很重要。因此，在这项应用中，我们将建立特定的分子成像技术来研究器官系统的生长和发育，并增强该模型研究人类疾病影响的潜力。

DESCRIPTION (provided by applicant): There is an increasing call for alternative animal models as surrogates for assessing risks to human health. The see-through medaka is a unique animal model, which we believe has enormous potential for assessing such risks. This animal model is transparent in embryonic, juvenile and adult life stages with principal internal organs visible through the body wall in the living animals. With the see-through medaka, ease of phenotypic analysis currently available in existing alternative models during embryogenesis may now be extended to later life stages. Structural and functional changes at molecular, cellular, tissue and organ/system levels may be imaged non-invasively leading to greatly enhanced phenotypic characterization throughout life. Four specific aims are proposed: 1) Define medaka liver growth and development emphasizing relationship of hepatic tubules to microvasculature. 2) Image hepatocyte and biliary epithelial cell interaction in bile formation within the hepatic tubule. 3) Construct cell type specific transgenic see-through medaka to extend noninvasive detection of liver development/remodeling and growth. 4) To produce verified hepatic injury in larval see-through medaka by exposure to a reference hepatotoxin known to target intrahepatic biliary function, and, in separate individuals, to a known carcinogen that results in degenerative and neoplastic lesions in medaka liver. The compressed life cycle of the medaka, when coupled with its transparent features, makes this model particularly well suited to study post-embryonic development, aging, toxicity, mutagenesis and carcinogenesis. Particularly important is a model for evaluating manifestations of early life stage exposure where initial molecular derangement may be separated from adult dysfunction by long intervals. Effort in the proposed research will focus on processes to extend noninvasive detection of liver development/remodeling and growth. We have chosen to study the liver because of our extensive knowledge with this organ system and it's importance in: uptake, metabolism, storage and redistribution of nutrients and other endogenous molecules, metabolism of xenobiotics, and formation and excretion of bile. Thus, in this application, we will establish specific molecular imaging technologies to study organ system growth and development and to enhance this model's potential to study effects of human disease.