Brash James T, Ruhrberg Christiana, Fantin Alessandro
UCL Institute of Ophthalmology, University College London.
UCL Institute of Ophthalmology, University College London;
J Vis Exp. 2018 Jun 19(136):57524. doi: 10.3791/57524.
The primary function of the vascular endothelium in vertebrate organisms is to serve as a barrier between the blood and each tissue of the body, whereby the permeability of the endothelium to blood cells, plasma macromolecules, and water can be adapted according to the physiological need. In certain diseases, cytokines and growth factors are released that target the endothelial barrier to transiently increase vascular permeability; however, their prolonged presence may cause chronic vascular hyperpermeability and thereby tissue-damaging edema. The Miles assay is an in vivo technique that allows researchers to study vascular hyperpermeability through the proxy measurement of vascular leakage. Here, we provide a detailed protocol on how to perform this procedure in the mouse, which is the most widely used model organism to study mammalian physiology and pathology. The procedure involves the intravenous injection of Evans blue dye to label the circulating albumin followed by multiple intradermal injections of permeability-inducing agents and vehicle control solutions into opposing flanks of the mouse. Consequently, Evans blue dye gradually leaks into the dermis, where it accumulates and can be extracted for quantification as leakage induced by the permeability-inducing agent relative to the vehicle. The Miles assay can be performed in wild type or genetically modified mouse models and may be combined with drug administration to study molecular mechanisms that regulate vascular permeability and identify agents/targets capable of inducing or blocking hyperpermeability.
在脊椎动物机体中，血管内皮的主要功能是充当血液与身体各组织之间的屏障，借此内皮对血细胞、血浆大分子和水的通透性可根据生理需求进行调节。在某些疾病中，会释放细胞因子和生长因子，这些因子作用于内皮屏障，使血管通透性短暂增加；然而，它们的长期存在可能导致慢性血管高通透性，进而引发组织损伤性水肿。迈尔斯试验是一种体内技术，研究人员可通过间接测量血管渗漏来研究血管高通透性。在此，我们提供一份详细方案，介绍如何在小鼠身上进行该实验，小鼠是研究哺乳动物生理学和病理学最常用的模式生物。该实验过程包括静脉注射伊文思蓝染料以标记循环中的白蛋白，随后在小鼠相对的两侧皮内多次注射通透性诱导剂和溶剂对照溶液。结果，伊文思蓝染料逐渐渗漏到真皮中，在那里积聚，可提取出来进行定量分析，以确定相对于溶剂而言，通透性诱导剂所引起的渗漏情况。迈尔斯试验可在野生型或基因改造小鼠模型中进行，并且可与药物给药相结合，以研究调节血管通透性的分子机制，并识别能够诱导或阻断高通透性的药物/靶点。
