Nanoparticle Induced Circuit Excitation

描述（由申请人提供）：提出了一组实验来验证和进一步开发一种新的基于纳米颗粒的技术，纳米颗粒诱导电路激发（NICE），用于远程和非侵入性地调节细胞的活性。生物学的一个基本目标是了解每种细胞类型在复杂生物体中的作用。细胞功能的决定性测试是选择性地打开或关闭活动物中单个细胞类型的活性，并检查对生理功能的影响。最近的工具，如光激活的离子通道，如通道视紫红质，开创了在遗传定义的细胞膜电位的外部控制，并建立了一个新的手段，神经科学家的调查。然而，这些光学方法具有限制其应用的实际缺点，包括需要手术植入侵入性光纤;不能同时刺激多个解剖区域中的细胞;以及难以并行调节多种细胞类型。 我们通过使用纳米粒子用无线电波远程激活定义的细胞群来应对这一挑战。用链霉亲和素包被的氧化铁用于装饰细胞，其在细胞特异性启动子的控制下表达生物素受体蛋白。这些相同的细胞也被工程化以表达TRPV 1，TRPV 1是一种单组分、温度敏感的离子通道，其可以检测生理范围内的温度的微小变化，并且通过构象变化允许分级的钙进入。将金属包被的细胞暴露于限定的电磁场会增加局部温度并激活TRPV 1通道，从而导致Ca 2+电流和细胞激活。我们有初步的数据证实了这种方法在体外的有效性，现在建议扩展我们的研究，以进一步验证体外技术，并调节体内功能，如激素释放和神经活动。我们还将建立一种方法，使用修饰的TRPV 1和由其他金属制成的纳米颗粒组合激活不同的细胞，这些金属可以在不同的波长下激发。我们将使用这个工具来研究特定的外周和中枢神经系统细胞群在能量代谢中的作用。我们建议分三个阶段开发这种方法：1）验证NICE在体外的安全性和实用性，并通过用调谐到不同波长的不同颗粒装饰不同的细胞类型来改进方法，以激活各种组合的不同细胞群的集合。2)建立NICE调节激素释放以调节体内糖尿病动物葡萄糖代谢的能力。3)表明NICE可用于刺激电兴奋细胞的动作电位以改变行为，并使用NICE研究特定下丘脑群体（NPY和POMC）控制食欲的作用。 随着时间的推移，NICE可以适用于临床应用，例如：经工程改造以表达NICE构建体的诱导多能干细胞可以充当自体移植物以使得能够对细胞功能进行外部控制。这些应用是遥远的，但并非不可想象的，所提出的研究可能为纳米颗粒的临床应用奠定基础。

DESCRIPTION (provided by applicant): A set of experiments is proposed to validate and further develop a new nanoparticle based technology, Nanoparticle induced Circuit excitation (NICE), for modulating the activity of cells remotely and non-invasively. A fundamental goal of biology is to understand the role of each cell type in a complex organism. The definitive test of cell function is to selectively turn on or off the activity of a single cell type in a living animal and examine the effect on physiological function. Recent tools, such as light activated ion channels such as channel rhodopsin, have pioneered the external control of membrane potential in genetically defined cells and established a new means for investigation by neuroscientists. However, these optical methods have practical disadvantages limiting their application including the need for surgical implantation of invasive fiber optics; the inability to stimulate cells in multiple anatomical regions simultaneously; and the difficulty of modulating multiple cell types in parallel. We address this challenge by using nanoparticles to activate defined cell populations remotely with radiowaves. Ferrous oxide coated with streptavidin is used to decorate cells, which express a biotin acceptor protein under the control of cell specific promoters. These same cells are engineered to also express TRPV1, a single component, temperature-sensitive ion channel that can detect small changes in temperature within the physiological range and by conformational change allow graded calcium entry. Exposing the metal coated cells to a defined electromagnetic field increases the local temperature and activates TRPV1 channels resulting in a Ca2+ current and cell activation. We have preliminary data that confirms the efficacy of this method in vitro and now propose to extend our studies to further validate the technology in vitro and to modulate in vivo functions such as hormone release and neural activity. We will also establish a means for combinatorial activation of different cells using a modified TRPV1 and nanoparticles fabricated from other metals that can be excited at different wavelengths. We will use this tool to examine the roles of specific peripheral and CNS cell populations in energy metabolism. We propose to develop this method in three stages: 1) Validate the safety and utility of NICE in vitro and refine the methodology by decorating different cell types with distinct particles tuned to different wavelengths to activate ensembles of different cell populations in various combinations. 2) Establish the ability of NICE to modify hormone release to regulate glucose metabolism in diabetic animals in vivo. 3) Show that NICE can be used to stimulate action potentials in electrically excitable cells to modify behavior and use NICE to investigate the role of specific hypothalamic populations in (NPY and POMC) to control appetite. In time, NICE may be adapted for clinical uses, e.g: induced pluripotent stem cells engineered to express NICE constructs may act as autografts to enable external control of cell function. These applications are distant but not inconceivable and the studies proposed may form the foundation for the clinical use of nanoparticles.