Novel Technology for Screening Receptor and Compound Libraries in Drug Discovery

描述（由申请人提供）：制药/生物技术行业的发现研究利用高通量，无标签药物结合细胞分析，其中许多是功能分析。在这种情况下，受体-配体相互作用只是结合的间接测量，可能取决于激活途径的结合阈值。辐射监测设备公司（RMD）提议开发一种平台技术和设备，能够高通量筛选生物/药理学活性分子及其同源受体之间的关联。这项技术是基于纳米粒子的磁双折射弛豫分析，将特别设计用于筛选痛觉肽受体和相互作用的配体。RMD已经证明，配体修饰的磁赤铁矿纳米颗粒在与蛋白质、病毒和小尺寸微生物结合时，表现出更长的磁性双折射弛豫时间。双折射的绝对大小和弛豫时间仅取决于“受体-配体复合物”形成时的水动力体积变化，而不受过量未结合配体的影响。这些特性使该试验非常适合筛选固定在磁性纳米颗粒表面的分子。验证概念的实验平台将利用固定在磁性纳米颗粒表面的肽配体（痛觉肽及其衍生物），在与细菌和酵母等微生物细胞表面过度表达的痛觉肽受体结合时，将对其进行磁双反射松弛变化的筛选。使用磁光双折射来识别配体和受体相互作用的基本原理是，它消除了将未结合的配体与受体捕获的配体分离的需要。由于在检测之前不需要将样品与捕获颗粒分离，因此减少了识别时间。重要的是，不需要外源性荧光或放射性标签附着到受体或配体上。此外，这种新方法适用于配体与同源受体的相互作用不激活细胞内通路的系统，这很容易用比例荧光测量平台监测。该程序/设备将用于制药/生物技术行业的广泛应用，包括开发小分子药物的发现研究以及从展示库中鉴定生物活性肽和蛋白质。另一个应用是孤儿受体的鉴定和感兴趣配体受体的发现。

DESCRIPTION (provided by applicant): Discovery research in the pharmaceutical/biotech industries utilizes high throughput, label-free drug binding cell-based assays, many of which are functional assays. In such instances, the receptor-ligand interaction is only an indirect measurement of binding and might depend on a threshold of binding for activation of the pathway. Radiation Monitoring Devices, Inc. (RMD) proposes to develop a platform technology and device capable of high throughput screening for association between biologically/pharmacologically active molecules and their cognate receptors. This technology is based on assaying magnetic birefringence relaxation of nanoparticles and will be particularly designed for screening nociceptin receptor and interacting ligands. RMD has demonstrated that maghemite nanoparticles, decorated with ligand molecules, exhibit longer magnetic birefringence relaxation times when associated with proteins, viruses and small size microorganisms. The absolute magnitude of birefringence and the relaxation time depends only on the hydrodynamic volume change upon formation of the "receptor-ligand complex" and is not affected by excess unbound ligand. These properties make this assay ideal for screening molecules immobilized on the surface of magnetic nanoparticles against receptors. The assay platform to demonstrate the proof of concept will utilize a peptide ligand (nociceptin and derivatives) immobilized on the surface of magnetic nanoparticles, which will be screened for a change in magnetic birefringence relaxation upon binding to nociceptin receptor overexpressed on the cell surface of microorganisms such as bacteria and yeast. The rationale for using magneto-optical birefringence to identify ligand and receptor interactions is that it eliminates th need for separating the unbound ligands from ligands captured by receptors. The time to identification is reduced since there is no need to segregate sample from the capture particle before detection. Importantly, attachment of an exogenous fluorescent or radioactive label to the receptor or ligand is not required. Further, this novel approach is applicable in systems where the interaction of ligand with cognate receptor does not activate intracellular pathways that are easy to monitor with a ratiofluorometric platform. This procedure/device will be useful for a broad range of applications in the pharmaceutical/biotechnological industry including discovery research to develop small molecule drugs and the identification of biologically active peptides and proteins from display libraries. Another application is the identification of orphan receptors and discovery of receptors for ligands of interest. PUBLIC HEALTH RELEVANCE: The endogenous neuropeptide ligand-receptor system, the nociceptin/nociceptin receptor, is involved in a wide range of physiological responses including in reward elicited by ethanol consumption and drug abuse and represents a viable drug target. We will develop a strategy and platform for screening compound libraries for the development of novel agonists and antagonists for the nociceptin/nociceptin receptor system. Such technology carries the potential of great health and socioeconomic impact as the underlying molecular components that define drug and alcohol addiction behavior will provide insight into ways that addiction can be treated more effectively.