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

摘要 微电极阵列(MEA)在直接脑-机接口(BCI)治疗中具有巨大的应用潜力 控制机器人假体以改善与丧失相关的衰弱状况患者的生活 指四肢或四肢功能。MEA还有可能恢复视觉、听力、 通过对感觉神经元施加图案化的电流刺激来获得触觉。就像这些一样有希望 治疗是，在植入MEA的当前技术状态下，有一个主要缺点是它们的记录 随着时间的推移，刺激质量会下降，植入物最终会变得不起作用。它们的用途是 治疗持续患者一生的慢性疾病的治疗设备需要稳定的MEA 几十年，而不是几个月到几年。导致慢性种植失败的潜在机制 MEAs尚未完全阐明。一种可能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异物反应。因以下原因引起的炎症 小胶质细胞和星形胶质细胞的激活可导致胶质增生和形成包裹着 装置，防止对神经元的有效记录和刺激。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反应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(SNPs)作为一种 用于微电极的多功能表面改性。PEDOT/SNP包覆MEAs 与标准裸金属电极相比，具有更好的电化学性能和负载容量 由于其具有高比表面积的多孔结构，因此具有治疗性化合物。这些特性使Meas 包被PEDOT/SNP是高靶向性基因传递的理想平台，因为二氧化硅纳米颗粒可以 有效地装载了DNA。这项建议旨在开发这项技术，以有效地基因修饰小胶质细胞 局部植入MEA以减少炎症并测量炎症对录音的影响 质量和增产效率，以及设备的长期稳定性。此外，我将调查如何改变 在异物反应中影响种植体周围组织的重塑。我将采取的方法是 靶向炎症途径的CRISPR基因治疗载体负载SNP包被的MEAs 在小胶质细胞中。CRISPR载体将以电化学的方式传递给直接与 植入的装置。这项技术的发展对提高糖尿病的治疗价值具有巨大的潜力。 通过减少炎症和胶质增生来提高植入设备的性能和寿命，并 增加我们对大脑对植入设备的反应的基本了解。一旦确立，这一点 技术将成为高靶向性基因传递的通用平台，既有时空的，也有细胞类型的 专一性。

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.