Nanoparticle Coated Microelectrode Arrays for Electrochemically Controlled Gene Editing at the Electrode Site

摘要 微电极阵列在直接脑-机接口（BCI）中具有巨大的治疗应用潜力 控制机器人假肢，以改善因失去亲人而衰弱的病人的生活 肢体或肢体功能。多边环境协定还具有恢复视觉、听觉、 和触觉的感觉。像这样有前途的 治疗是，目前植入MEA的最新技术水平存在一个主要缺点，即它们的记录 并且刺激质量随着时间的推移而降低，并且植入物最终变得不起作用。它们用作 用于治疗持续患者一生的慢性疾病的治疗装置需要MEA， 而不是几个月到几年。导致长期植入失败的潜在机制 多边环境协定尚未得到充分阐明。一个候选因素是电极或绝缘材料的退化， 机械设备故障。另一个重要因素是宿主的异物反应。引起的炎症 小胶质细胞和星形胶质细胞的活化可导致神经胶质增生和形成包裹神经胶质细胞的“胶质瘢痕”。 设备和防止有效的记录和刺激神经元。最近，基于基因治疗的干预措施 使用CRISPR/Cas系统进行基因敲除在改变免疫应答方面显示出巨大的前景。 Cui实验室最近的工作表明，使用功能化二氧化硅纳米颗粒（SNP）作为 用于微电极的多功能表面改性。用聚乙烯二氧噻吩（PEDOT）/SNP涂覆的MEA 具有优于标准裸金属电极的改进的电化学性能和负载容量 由于它们具有高表面积的多孔结构，这些特性使多边环境协定 涂有PEDOT/SNP的二氧化硅纳米颗粒是高度靶向基因递送的理想平台， 有效地装载了DNA该提案旨在开发这种技术来有效地基因修饰小胶质细胞 局部围绕植入的MEA，以减少炎症并测量炎症对记录的影响 质量和刺激效率，以及长期设备稳定性。此外，我将研究如何改变 异物反应影响植入物周围组织的重塑。我将采取 用编码靶向炎症通路的CRISPR基因治疗载体的DNA加载SNP包被的MEA 在小胶质细胞中。CRISPR载体将被电化学递送至与CRISPR载体直接介接的细胞。 植入装置。这项技术的发展具有很大的潜力，以提高治疗价值， 通过减少炎症和神经胶质增生来提高植入器械的性能和寿命， 增加我们对大脑如何响应植入设备的基本理解。一旦建立， 技术将是一个多功能的平台，高度靶向基因传递，具有时空和细胞类型 的特异性

Abstract Microelectrode arrays (MEAs) have great potential for therapeutic use in direct brain-computer interface (BCI) control of robotic prostheses to improve the lives of patients suffering from debilitating conditions related to loss of limbs or limb function. MEAs also have the potential to restore loss of sensory perception in vision, hearing, and tactile sensation by applying patterned current stimulation to sensory neurons. As promising as these therapies are, there is a major shortcoming to the current state of the art in implanted MEAs in that their recording and stimulation quality degrades over time, and the implants eventually become non-functional. Their use as therapeutic devices to treat chronic conditions that persist for the patient's life requires MEAs that are stable over decades rather than months to years. The underlying mechanisms leading to failure for chronically implanted MEAs have yet to be fully elucidated. One candidate is degradation of the electrode or insulation material leading to mechanical device failure. Another important factor is the host foreign body response. Inflammation due to activation of microglia and astrocytes can lead to gliosis and the formation of a “glial scar” encapsulating the device and preventing efficient recording and stimulation of neurons. Recently, gene therapy-based interventions using CRISPR/Cas systems for gene knockout have shown great promise in modifying the immune response. Recent work in the Cui lab has shown the efficacy of using functionalized silica nanoparticles (SNPs) as a versatile surface modification for microelectrodes. MEAs coated with polyethylenedioxythiophene (PEDOT)/SNP have improved electrochemical properties over standard bare metal electrodes and the capacity to be loaded with therapeutic compounds due to their porous structure with a high surface area. These properties make MEAs coated with PEDOT/SNP an ideal platform for highly targeted gene delivery, as the silica nanoparticles can be efficiently loaded with DNA. This proposal aims to develop this technology to efficiently gene modify microglia locally around implanted MEAs to reduce inflammation and to measure the effect of inflammation on recording quality and stimulation efficiency, as well as long-term device stability. In addition, I will investigate how changes in the foreign body response affect the remodeling of tissue surrounding the implant. I will take the approach of loading SNP coated MEAs with DNA encoding CRISPR gene therapy vectors targeting inflammatory pathways in microglia. The CRISPR vectors will be electrochemically delivered to cells directly interfacing with the implanted devices. The development of this technology has great potential to enhance the therapeutic value of implanted devices by increasing their performance and longevity by reducing inflammation and gliosis and to increase our fundamental understanding of how the brain responds to implanted devices. Once established, this technology will be a versatile platform for highly targeted gene delivery, having both spatiotemporal and cell-type specificity.