Optimization and Delivery of Bioactive Coating for High Yield and Stable Neural Recording

项目摘要 以单细胞分辨率长期监测神经元集合活动的能力 神经科学家们非常渴望的。已经开发了多种多电极阵列（MEA 用于体内研究。这些阵列能够揭示神经元集合的活性。不幸的是， 市场上没有一种设备完全能够获得同时高产量的记录 高质量，稳定，使用数月至数年。这一众所周知的挑战极大地 限制了我们在足够长的时间内跟踪单个神经元群体活动的能力， 研究学习和记忆、发育和衰老或疾病进展过程中的回路变化， 伤口愈合此外，脑机接口（BMI）的临床使用，它利用记录的神经元， 活动解码运动意图控制机器，已被阻碍的不稳定和不可靠的 录制. 我们开发了一种由脑源性L1细胞粘附分子组成的仿生涂层， 宿主组织的炎症反应在啮齿类动物中，L1涂层NeuroNexas探针保持了高质量的神经 在16周的时间内记录，具有显著更高的单位产量和信噪比， 未涂覆的对照探针。与此同时，在非人类灵长类动物（NHP）中使用L1涂层Blackrock MEA还表现出高质量的性能，在单位产量和信号幅度至少为6 个月MEA制造商和用户对利用这项技术表现出浓厚的兴趣。但 由生物蛋白质制成的涂层易碎并且在运输的恶劣环境中可能失去生物活性， 储存和灭菌。为了使L1涂层成为一种可以被广泛采用的技术， 神经科学界，我们建议优化涂层稳定性，并制定实用的协议， 涂层的保存、储存、包装、运输和灭菌。制备的涂层的生物活性 首先用细胞培养物测试不同的方案。有希望的程序将被测试， 在匹兹堡大学的啮齿类动物中植入和记录。一旦最佳涂层和程序 确定后，涂层阵列将交付给用户，以评估涂层性能。布扎奇博士 (NYU)将在自由活动的大鼠中测试L1涂层的NeuroNexas阵列。Schwartz博士（美国）Pitt）和Chestek博士 （美国）Michigan）将在NHP中测试L1涂层Blackrock阵列，用于BMI研究。用户将与我们密切合作 为了确定其记录应用中的具体性能标准，比较涂层和 未涂层阵列，并为我们提供用户输入，以改善包装和交付。在整个项目中， 来自两家MEA制造商Blackrock Microsystems和NeuroNexus Technology的代表将 作为顾问，确保我们的程序与他们的设备兼容，并指导我们 传播。 该项目将产生一种涂层技术，既易于采用，又可推广到所有类型的国家- 新兴的多边环境协定。解决灭菌、包装和交付等实际问题是关键的一步 将该技术转化为商业和临床应用。高质量和稳定的神经记录将 大大提高了我们在长期实验中绘制大脑活动的能力，并有利于脑机接口 和其他类型的神经假体。从更广泛的意义上说，这里制定的协议是为了保护 固定化蛋白在贮存、运输和灭菌过程中的应用应适用于其他医疗植入物 包含生物活性蛋白质、免疫测定、蛋白质阵列、基于酶的生物传感器或任何微/纳米 包含生物成分的设备。

Project Summary The ability to monitor activity of ensembles of neurons at single-cell resolution, chronically, over long time periods is greatly desired by neuroscientists. A variety of multi-electrode arrays (MEAs) have been developed for in vivo studies. These arrays are capable of revealing the activity of neuronal ensembles. Unfortunately, none of the devices on the market is fully capable of obtaining recordings that are simultaneously high-yield and high-quality, as well as stable and useful over months to years. This well-known challenge has greatly limited our ability to track the activity of populations of single neurons over a sufficient period of time to fully investigate circuit change during learning and memory, development and aging, or disease progression and wound healing. Additionally, the clinical use of brain machine interface (BMI), which utilize recorded neural activities to decode movement intent for controlling machine, has been hindered by the unstable and unreliable recording. We have developed a biomimetic coating composed of a brain-derived L1-cell adhesion molecule that mitigate the inflammatory host tissue reaction. In rodents, L1 coated NeuroNexas probes maintained high quality neural recording over the period of 16 weeks with significant higher single unit yield and signal to noise ratio than the uncoated control probes. Meanwhile, recordings in non-human primates (NHPs) with L1-coated Blackrock MEAs also demonstrated high quality performance in single unit yield and signal amplitude for at least 6 months. MEA manufacturers and users expressed strong interest in utilizing this technology. However, the coating made of biological protein is fragile and may lose bioactivity during the harsh environment of shipping, storage and sterilization. In order to make the L1 coating a technology that can be widely adopted by the neuroscience community, we propose to optimize the coating stability and develop practical protocols for coating preservation, storage, packaging, delivery and sterilization. The bioactivity of the coating prepared with different protocols will first be tested with cell cultures. Promising procedures will then be tested with implantation and recording in rodents at the University of Pittsburgh. Once optimum coating and procedures are determined, coated arrays will be delivered to users to evaluate the coating performance. Dr. Buzsaki (NYU) will test the L1 coated NeuroNexas arrays in freely moving rats. Dr. Schwartz (U. Pitt) and Dr. Chestek (U. Michigan) will test the L1 coated Blackrock arrays in NHPs for BMI studies. Users will work closely with us to define specific performance criteria in their recording applications, compare performance of coated and uncoated arrays, and provide user input for us to improve the packaging and delivery. Throughout the project, representatives from two MEA manufacturers, Blackrock Microsystems and NeuroNexus Technology, will serve as consultants to ensure compatibility of our procedures with their devices and guide us on the path to dissemination. The project will produce a coating technology that is both easy to adopt and generalizable to all types of state- of-art and emerging MEAs. Solving the practical issues of sterilization, packaging and delivery is a critical step toward commercial and clinical translation of the technology. High quality and stable of neural recording will greatly improve our ability to map brain activity in long-term experiments, and benefit brain-computer interfaces and other types of neural prostheses. In a broader sense, the protocols developed here for preserving immobilized protein during storage, delivery and sterilization should be applicable to other medical implants containing bioactive proteins, immunoassays, protein arrays, enzyme-based biosensors or any micro/nano devices that incorporate biological components.