Development and validation of an intraoperative imaging agent for the peripheral nervous system

项目摘要/摘要 2000万美国人因创伤和医疗疾病导致周围神经损伤，导致 在一系列潜在的令人衰弱的副作用中。在四分之一的病例中，患者认为手术是 他们神经损伤的根本原因。特别是在肿瘤切除期间或在创伤、组织变形 低能见度可能会挑战外科医生精确定位和保护周围神经的能力。凭直觉， 如果能用外源性造影剂突出神经，手术结果将会大大改善。 探员。然而，在临床实践中，目前的护理标准--肉眼检查和触诊--仍然存在 保持不变。 外科医生在手术过程中无法识别神经，这是一个巨大的未得到满足的临床需求，我们 建议在此应用程序内解决。我们将开发并验证一种翻译荧光显像剂 对于外周神经系统来说。在为临床试验做准备时，我们将在小鼠和大型动物身上展示 该制剂在人体内使用是安全的。具体地说，这项提议以Hsp1a为中心，这是我们分离的一种肽 来自秘鲁狼蛛的毒液Homeomma Spec.秘鲁，我们发现它对 人类导航1.7。已有研究表明，Nav1.7在人类周围神经组织中高表达。我们相信 荧光Hsp1a在手术中作为可注射的术中指南将具有巨大的价值，以及 该制剂将为外科医生提供额外的对比剂，从而减少医源性损伤，从而减少外科手术 发病率。 为了实现这一目标，我们集合了三个具体目标(SA)，每个目标都将探索一个不同的目标 向人们展示了荧光Nav1.7示踪剂可以转化到临床上。在SA1中，并由我们的 原则证明数据，我们将合成一个荧光标记的Hsp1a衍生物文库(n=20)，其特征是 不同的荧光团、附着点和连接物长度。对于所有衍生品，我们将确定IC50值 使用膜片钳电生理学对抗Nav1.7；在SA2中，药物动力学和体内表现将 用Nav1.7表达的荷瘤裸鼠和Nav1.7缺陷的Scn9atm1Dgen/J小鼠进行检测。 对于最有希望的示踪剂(n=3，基于IC50和信噪比)，我们将测试最小可检测到的 猪群中的剂量。在SA3中，我们将询问最有希望的Hsp1a的药效学特性 多肽。我们将在监测心血管疾病的同时确定小鼠的最大耐受量 呼吸功能。对于主要候选者，我们将进行两种GLP毒性研究(小鼠和狗)。如果 如果成功，目前的研究方案和生成的数据将成为临床I期试验的基础 口腔癌患者中携带Hsp1a。

Project Summary/Abstract Twenty million Americans suffer from peripheral nerve injury caused by trauma and medical disorders, resulting in a broad spectrum of potentially debilitating side effects. In one out of four cases, patients identify surgery as the root cause of their nerve injury. Particularly during tumor resections or after traumatic injuries, tissue distortion and poor visibility can challenge a surgeon's ability to precisely locate and preserve peripheral nerves. Intuitively, surgical outcomes would improve tremendously if nerves could be highlighted using an exogeneous contrast agent. In clinical practice, however, the current standard of care – visual examination and palpation – remains unchanged. The inability of surgeons to identify nerves during surgery represents an immense unmet clinical need, which we propose to address within this application. We will develop and validate a translational fluorescent imaging agent for the peripheral nervous system. In preparation for a clinical trial, we will show in mice and large animals that the agent is safe for use in humans. Specifically, this proposal centers on Hsp1a, a peptide which we isolated from the venom of a Peruvian tarantula, Homoeomma Spec. Peru, and which we found to be highly specific for human Nav1.7. It has been shown that Nav1.7 is highly expressed in human peripheral nerve tissue. We believe that a fluorescent Hsp1a will have tremendous value as an injectable, intraoperative guide during surgery, and that the agent will provide surgeons with additional contrast, reducing iatrogenic injury and therefore surgical morbidity. To achieve this goal, we have assembled three specific aims (SAs), each of which will explore a distinct goal toward showing that fluorescent Nav1.7 tracers can be translated to the clinic. In SA1, and supported by our proof-of-principle data, we will synthesize a library of fluorescently labeled Hsp1a derivatives (n = 20), featuring different fluorophores, attachment points and linker lengths. For all derivatives, we will determine the IC50 values against Nav1.7 using patch-clamp electrophysiology; in SA2, pharmacokinetics and in vivo performance will be determined using Nav1.7 expressing, tumor-bearing athymic nude mice and Nav1.7 deficient Scn9atm1Dgen/J mice. For the most promising tracers (n = 3, based on IC50 and signal/noise ratios), we will test the minimum detectable dose in cohorts of pigs. In SA3, we will interrogate the pharmacodynamic properties of the most promising Hsp1a peptides. We will determine the maximum tolerated doses in mice while monitoring cardiovascular and respiratory function. For the lead candidate, we will perform a 2-species GLP toxicity study (mice and dogs). If successful, the current research proposal and generated data will form the foundation of a clinical phase I trial with Hsp1a in oral cancer.