Volumetric optical connectome microscopy of human cerebellar circuitry

项目摘要/摘要 寻求K99/R00独立之路奖的目标是将自己确立为独立人士 研究正常人和脑内脑回路结构与功能关系的首席研究员 精神错乱。拟议的项目，由高分辨率理解人脑的需求驱动 高通量工具和我在用于神经成像的生物医学光学方面的丰富经验，旨在建立一个 重建人类小脑电路和神经元结构的通用工具，了解 小脑退行性疾病的破坏性影响，并结合MRI模型寻找新的生物标志物 这可能会影响临床评估。 尽管自圣地亚哥·拉蒙·卡哈尔的开创性工作 绘制轴突束，我们关于800-1000亿个神经元如何连接在一起形成复合体的知识 人脑的功能仍然有限。目前，还没有体积显微镜技术可以绘制 人脑的电路和结构具有高度的完整性。在这里，我建议开发一种体积光学 连接组显微镜(VOCM)，用于以前所未有的分辨率重建人类小脑和 规模，并从全球角度绘制连接和神经元结构图。VOCM基于 偏振敏感光学相干层析成像和振动切片机对大范围离体脑的成像 以微米级的分辨率。重要的是，这项技术允许体积重建保持 超高精度，无组织扭曲；因此克服了所有组织学100年来的挑战 基于追踪人类大脑中的长纤维束和检查复杂的皮质折叠的方法。这个 VOCM生成的高质量数据将适用于MRI模型，以构建超高分辨率的 人类小脑提供了当前MRI工具所不能提供的解剖标记。 通过应用VOCM，该项目进一步探索了小脑疾病的3D病理模式。多系统 小脑萎缩型(MSA-C)是一种致命性神经退行性疾病，表现为严重的小脑和 脑干萎缩。尽管发病率很低，但MSA-C与其他 神经系统疾病。研究MSA-C的神经解剖学基础和病理轨迹可以 促进我们对小脑疾病和小脑病变的影响的理解。尤其是， 该项目将描述与神经退行性变相关的结构和电路中断 MSA-C然后，我们将使用高分辨率的体外数据集在体内进行预测，并允许进行MRI 否则，这是不可能的评估。 这项拟议的研究是在马萨诸塞州综合医院(MGH)的Martinos中心进行的，该中心是一家 开发尖端生物医学技术并与大型社区互动的理想环境 具有多学科背景的专家。我已经组建了一个强大的指导团队：Bruce Fischl博士，主任 马蒂诺斯中心计算核心；马蒂诺斯中心光学部主任大卫·博阿斯博士； 以及MGH共济失调中心主任Jeremy Schmahmann博士。我将利用核磁共振建模中的正式培训 并分析与小脑相关的脑部疾病和神经病理学。神经解剖学的课程作业， 神经生物学和中枢神经疾病补充了我的生物医学光学背景，并促进了我的 关于重要的神经科学问题的知识。拟议的培训和研究将为我做好准备 必要的技能、新工具和有趣的数据，以启动独立的研究计划并进一步写作 在R00阶段完成后的研究补助金。我预计这项研究将极大地推动我们的 脑科学的最新知识，对临床革命产生影响，并倡导公众意识 在更大的人群中保持大脑健康。

Project Summary/Abstract The goal in seeking a K99/R00 Pathway to Independence Award is to establish myself as an independent principal investigator to study the structural-functional relationship of the brain circuitry in normal and brain disorders. The proposed project, driven by the need for understanding the human brain with high-resolution high-throughput tools and my extensive experience in biomedical optics for neuroimaging, aims to establish a versatile tool to reconstruct the circuitry and neuronal architecture in human cerebellum, understand the disruptive impacts of cerebellar degenerative disease, and combine with MRI models to seek novel biomarkers that will potentially influence the clinical assessment. Despite the tremendous advances of light microscopy since Santiago Ramón y Cajal's pioneering work in drafting axonal tracts, our knowledge on how the 80-100 billions of neurons connect together to form complex functions in human brain is still limited. Presently, there is no volumetric microscopy technique that can map the circuitry and architecture of human brain with high integrity. Here I propose to develop a volumetric optical connectome microscopy (VOCM), for reconstructing the human cerebellum with unprecedented resolution and scales, and mapping the connectivity and neuronal architectures from a global perspective. VOCM is based on a polarization sensitive optical coherence tomography and a vibratome slicer to image large-scale ex vivo brain at a micrometer-scale resolution. Importantly, this technology allows volumetric reconstruction preserving an ultra-high accuracy without tissue distortions; therefore overcomes the 100 years challenge of all histology based methods in tracing long fiber tracts and inspecting sophisticated cortical folding in the human brain. The high-quality data generated by VOCM will be fit into MRI models to construct an ultra-high resolution atlas of human cerebellum to provide anatomical labels that are not available in current MRI tools. By applying VOCM, the project further explores 3D pathological patterns of cerebellar disorder. Multiple system atrophy cerebellar type (MSA-C) is a fatal neurodegenerative disease manifested by severe cerebellar and brainstem atrophy. Despite its rare incidence, MSA-C shares common phenotypic characteristics with other neurological diseases. Studying the neuroanatomical substrates and pathological trajectory of MSA-C could advance our understanding of the impact of cerebellar disorders and cerebellar affected diseases. Particularly, the project will characterize the architecture and circuitry disruptions associated with neurodegeneration in MSA-C. We will then use the high-resolution ex vivo dataset to make predictions in vivo, and allow an MRI assessment that would not be possible otherwise. The proposed research is conducted at Martinos Center, Massachusetts General Hospital (MGH), which is an ideal environment developing cutting edge biomedical technologies and interacting with a large community of experts with multidisciplinary background. I have formed a strong mentoring team: Dr. Bruce Fischl, director of the Computational Core at Martinos Center; Dr. David Boas, director of the Optics Division at Martinos Center; and Dr. Jeremy Schmahmann, director of the MGH Ataxia Unit. I will leverage formal trainings in MRI modeling and analysis, cerebellar related brain diseases and neuropathology. The coursework on neuroanatomy, neurobiology and central nervous diseases complement my biomedical optics background and advance my knowledge on important neuroscience questions. The proposed trainings and research will prepare me with necessary skills, new tools, and intriguing data to launch an independent research program and writing further research grants after the completion of the R00 phase. I expect that the research will dramatically advance our current knowledge on brain science, have an impact on clinical revolutions, and advocate public awareness of brain health in greater populations.