Wireless Optogenetics by relay nano-illuminators

中继纳米照明器的无线光遗传学

• 批准号: 8743294
• 负责人: Gang Han
• 金额: $ 33.5万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-26 至 2017-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8743294
• 关键词: Address; Animals; Area; Behavior; Behavior Control; Biocompatible; Biological; Brain; Brain region; Cell physiology; Chronic; Combinatorial Synthesis; Development; Diffusion; Disease; Exhibits; Fiber; Fiber Optics; Gene Transfer Techniques; Generations; Genes; Genetic; Goals; Growth; Halorhodopsins; Health; Human; Implant; In Vitro; Individual; Inflammation; Infrared Rays; Injection of therapeutic agent; Laboratories; Lanthanoid Series Elements; Lead; Left; Light; Mediating; Methods; Movement; Neurobiology; Neurons; Neurosciences; Opsin; Optics; Output; Particle Size; Penetration; Performance; Positioning Attribute; Property; Reaction; Resolution; Risk; Scheme; Science; Scientist; Signal Transduction; Slice; Solvents; Source; Surface; Temperature; Testing; Tissues; Transgenic Mice; Variant; Viral; Visible Radiation; Wireless Technology; awake; base; biomaterial compatibility; brain tissue; cranium; density; immunogenicity; in vivo; insight; interest; intravenous injection; microbial; nano; nanocrystal; nanoparticle; neural circuit; neuropsychiatry; novel; optical fiber; optogenetics; photonics; public health relevance; research study; spatiotemporal; tool

DESCRIPTION (provided by applicant): An important step toward better understanding neural circuit function was recently made possible thanks to the breakthrough development of optogenetic tools. In this approach, the microbial opsin genes [most notable, Channelrhodopsin (ChR-2) and halorhodopsin (NpHR)] are expressed in neurons either by viral transduction or transgenesis. Neurons expressing opsin can then be activated or inhibited by light at specific wavelengths. Due to its great spatiotemporal resolution, optogenetics is able to functionally dissect brain circuits, as well as to offer new insights into the causal relationship between brain activity and behavior and, possibly, lead to therapies for neuropsychiatric diseases. However, due to the limited tissue penetration of light at the wavelengths necessary to activate optogenetic constructs, the stimulation of behaving animals has to rely on chronically implanted, fiber-optics or mounted LEDs to deliver light into deep brain tissues. Although this method is very useful and has yielded a wealth of information about brain circuits, stimulation via fiber-optics also has important limitations, particularly in regard to chronic stimulation in awake animals. To address this challenging issue, we propose to develop a wireless optogenetic strategy to remotely activate opsins in vivo using a relay nano- illuminator. This approach is buil upon key technologic advances recently made in our laboratory in lanthanide-doped upconversion nanoparticles (UCNPs), a new generation of nanoparticles with unexpected properties. The most significant advantage of UCNPs is their unnatural inverse excitation and emission profiles; i.e., they are excited using biocompatible, low power, deep tissue-penetrant, near infrared radiation that is effectively converted to a higher energy output emission at various shorter wavelengths, including visible light for activation of opsins. We propose two specific aims. For Aim 1, we will characterize the ability of UNCPs to act as "relay illuminators" in vitro and in vivo. We will initially focus on the first generation of UCNP nanoparticles (CaF2 coated core/shell UCNP) that our preliminary experiments have demonstrated to exhibit robust emission from deep brain tissue. In Aim2, we will develop novel combinatorial synthesis to enhance optogenetic performance of lanthanide-doped UCNPs. This new strategy will overcome many of the limitations of current fiber-optic based approaches, and will enable new applications in both fundamental science and human health.

描述（由申请人提供）：由于光遗传学工具的突破性发展，最近朝着更好地理解神经回路功能迈出了重要的一步。在这种方法中，微生物视蛋白基因[最值得注意的是，视紫红质（ChR-2）和盐视紫红质（NpHR）]通过病毒转导或转基因在神经元中表达。然后，表达视蛋白的神经元可以被特定波长的光激活或抑制。由于其出色的时空分辨率，光遗传学能够从功能上剖析大脑回路，并为大脑之间的因果关系提供新的见解 活动和行为，并可能导致神经精神疾病的治疗。然而，由于激活光遗传构建体所需波长的光的有限组织穿透，行为动物的刺激必须依赖于长期植入的光纤或安装的LED来将光递送到深部脑组织中。虽然这种方法非常有用，并且已经产生了大量关于脑回路的信息，但通过光纤进行刺激也有重要的局限性，特别是在清醒动物的慢性刺激方面。为了解决这个具有挑战性的问题，我们提出开发一种无线光遗传学策略，使用中继纳米照明器在体内远程激活视蛋白。这种方法是建立在我们实验室最近在镧系元素掺杂的上转换纳米粒子（UCNPs），具有意想不到的性能的新一代纳米粒子的关键技术进展。UCNP的最显著的优点是它们的非自然逆激发和发射曲线;即，它们使用生物相容的、低功率的、深层组织穿透的、近红外辐射来激发，该近红外辐射在不同的温度下有效地转换成更高能量的输出发射。 更短的波长，包括用于激活视蛋白的可见光。我们提出两个具体目标。对于目标1，我们将描述UNCP在体外和体内充当“中继照明器”的能力。我们将首先关注第一代UCNP纳米颗粒（CaF 2包覆的核/壳UCNP），我们的初步实验已经证明，该纳米颗粒表现出来自深部脑组织的强大发射。在Aim 2中，我们将开发新的组合合成以增强镧系元素掺杂的UCNP的光遗传学性能。这一新策略将克服目前基于光纤的方法的许多局限性，并将在基础科学和人类健康方面实现新的应用。