Monitoring neuronal activity with a blood test - Released Markers of Activity (RMA)

通过血液测试监测神经元活动 - 释放的活动标记 (RMA)

• 批准号: 10687503
• 负责人: Jerzy Olgierd Szablowski
• 金额: $ 140.85万
• 依托单位: RICE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-04 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10687503
• 关键词: Acoustics; Area; Bar Codes; Biochemical; Blood; Blood Tests; Blood specimen; Brain; Brain imaging; Brain region; Cells; Clinical; Color; Contrast Media; Data; Detection; Discipline; Environment; Equipment; FOS gene; Fright; Gene Expression; Genes; Genetic; Laboratories; Location; Magnetic Resonance Imaging; Mass Spectrum Analysis; Measures; Monitor; Neurons; Peptides; Physiological Processes; Physiology; Process Measure; Proteins; Reader; Reporter; Science; Serum Markers; Signal Transduction; System; Tissues; Viral Vector; activity marker; cost; cranium; fear memory; implantable device; in vivo; innovation; innovative technologies; neuroregulation; response; single molecule; tool; treatment of anxiety disorders

Project Summary Blood tests are among the most common clinical tools due to their low cost, simplicity, and ability to observe many markers at once. However, currently blood tests can only monitor a fraction of physiological processes that happen to have a serum marker. What if we made synthetic serum markers that can track other physiological processes? The PI has recently developed such markers called Released Markers of Activity or RMAs. RMAs are expressed in the brain in response to a physiological process, such as neuronal activity, but then exit into blood for simple detection. In our preliminary data, RMAs could monitor expression in as few as 10s-100s of cells in the brain and show signal levels up to 39,000-fold over baseline when monitoring a single brain region. The PI was able to use RMAs to measure neuronal (c-Fos) activity in specific brain regions with a simple blood test. Since this discovery, our laboratory has been working on the new paradigm of ‘imaging’ the brain with blood sampling. This approach has many advantages. First, typical reporters need to be measured within the brain where access is difficult and the signal is compromised by surrounding tissue. Our key innovation is to keep record of the RMA’s location in the brain, but access it with a simple blood test that is not compromised by the skull, tissue scattering, or high background from surrounding cells. Second, there is a large number of genes in each cell and tens of distinct brain regions, but available reporters can at most represent only a few signals (e.g. a few colors of fluorescent proteins). RMAs use biochemical detection and thus can be massively multiplexed similarly to how thousands of proteins can be detected in blood simultaneously using mass spectrometry. Third, RMAs can surveil large brain regions, unlike invasive locally-implanted devices. Finally, RMAs are inexpensive and easy to use - they are genetically encoded proteins and can use simple equipment such as a plate reader. The PI has a track record of developing innovative technologies that blend interfaces of multiple disciplines, such as genetically-encoded MRI contrast agents, Acoustically Targeted Chemogenetics (ATAC) for noninvasive neu- romodulation, or acoustically-targeted viral vectors (AAV.FUS). In this proposal, the PI will use cutting-edge single-molecule protein detection to increase sensitivity of RMAs from 10s-100s of cells to single neurons. Then we will develop ‘fast’ RMAs that can measure more rapid changes in gene expression. Finally, we will enable massively-multiplexed readout of RMAs using peptide barcoding to track gene expression in multiple brain re- gions at once, and, if feasible, in single cells in whole brain regions. Using RMAs we will enable a previously inaccessible study. We will monitor activity of neurons encoding a fear memory and measure whether activation of these neurons in safe environment is responsible for fear renewal, a finding that would have broad implications for treatment of anxiety disorders. New reporters, such as fluorescent proteins historically enabled broad discov- ery. RMAs too have the potential to transform broad areas of science as they can be adapted to noninvasively track different in vivo systems and tissues with single-cell sensitivity, massive multiplexity, and low cost.

项目概要 血液检测因其成本低、简单且能够观察而成为最常见的临床工具之一 然而，目前血液测试只能监测一小部分生理过程。 如果我们制造出可以追踪其他生理功能的合成血清标记，结果会怎样？ PI 最近开发了称为“已发布活动标记”或“RMA”的标记。 在大脑中表达以响应生理过程，例如神经活动，但随后退出 在我们的初步数据中，RMA 可以在短短 10 到 100 秒内监测表达。 当监测单个大脑区域时，大脑中的细胞显示的信号水平比基线高出 39,000 倍。 PI 能够使用 RMA 通过简单的血液测量特定大脑区域的神经元 (c-Fos) 活动 自从这一发现以来，我们的实验室一直致力于研究用血液对大脑进行“成像”的新范例。 这种方法有很多优点，首先，需要在大脑内测量典型的生产者。 在难以进入且信号受到周围组织影响的情况下，我们的关键创新是保持。 记录 RMA 在大脑中的位置，但可以通过简单的血液测试来访问它，该测试不会受到 头骨、组织分散或周围细胞的高背景。 其次，存在大量基因。 每个细胞和数十个不同的大脑区域，但可用的产生最多只能代表几个信号（例如 几种颜色的荧光蛋白）。 RMA 使用生化检测，因此可以进行大规模多重检测。 类似于如何使用质谱法同时检测血液中的数千种蛋白质。 与侵入性局部植入设备不同，RMA 可以监视较大的大脑区域。最后，RMA 价格低廉。 并且易于使用 - 它们是基因编码的蛋白质，可以使用简单的设备，例如酶标仪。 该 PI 拥有开发融合多个学科接口的创新技术的记录，例如 作为基因编码的 MRI 造影剂，声学靶向化学遗传学 (ATAC) 用于非侵入性神经成像 在此提案中，PI 将使用尖端技术。 单分子蛋白质检测可提高 10-100 个细胞对单个神经元的 RMA 敏感性。 我们将开发“快速”RMA，可以测量更快速的基因表达变化。 使用肽条码对 RMA 进行大规模多重读出，以追踪多个脑再灌注中的基因表达 一次离子，如果可能的话，在整个大脑区域的单个细胞中，我们将启用先前的离子。 我们将监测编码恐惧记忆的神经元的活动并测量是否激活。 安全环境中的这些神经元负责恐惧更新，这一发现将产生广泛的影响 用于治疗焦虑症的新生产者，例如荧光蛋白，使得历史上广泛的发现成为可能。 RMA 也有潜力改变广泛的科学领域，因为它们可以适应非侵入性。 以单细胞灵敏度、大规模多重性和低成本追踪不同的体内系统和组织。