Role of Microglia in Cerebral Small Vessel Disease (CSVD)/Vascular Cognitive Impairment (VCI)

小胶质细胞在脑小血管病 (CSVD)/血管认知障碍 (VCI) 中的作用

• 批准号: 10662565
• 负责人: JONATHAN R WEINSTEIN
• 金额: $ 60.53万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-15 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10662565
• 关键词: Affect; Age; Astrocytes; Attenuated; Axon; Biological Markers; Brain; Brain imaging; Cell Lineage; Cell Separation; Cells; Cerebral Ischemia; Cerebral small vessel disease; Cerebrovascular Disorders; Cerebrovascular system; Cholesterol; Chronic; Clinical; Cognitive; Cognitive deficits; Collaborations; Complement; Complex; Corpus Callosum; Data; Data Set; Dementia; Diagnostic; Diet; Diffuse; Diffusion Magnetic Resonance Imaging; Disease; Disease Progression; Elements; Endothelial Cells; Exhibits; Functional disorder; Gene Expression; Genes; Genetic; Goals; Human; Image; Immune; Impaired cognition; Impairment; Infiltration; Inflammation; Injury; Ischemia; Ischemic Brain Injury; Knowledge; Laboratories; Laser Speckle Imaging; Learning; Leukoencephalopathy; LoxP-flanked allele; Macrophage; Macrophage Colony-Stimulating Factor Receptor; Magnetic Resonance Imaging; Mediator; Memory; Microglia; Modality; Modeling; Molecular Target; Monitor; Mus; Myelogenous; Myeloid Cells; Nature; Neurocognition; Neuroimmune; Neurologic; Oligodendroglia; Oncogenes; Outcome; Outcome Assessment; Pathogenesis; Pathologic; Pathology; Pattern; Peripheral; Pharmacotherapy; Phenotype; Population; Positron-Emission Tomography; Process; Radiology Specialty; Receptor Signaling; Recovery; Rest; Rodent; Rodent Model; Role; Series; Signal Transduction; TGFB1 gene; Tamoxifen; Therapeutic; Therapeutic Intervention; Time; Tissues; Transforming Growth Factors; Transgenic Mice; Universities; Vascular Cognitive Impairment; Vascular Dementia; antagonist; attenuation; cell type; cerebrovascular; clinically relevant; cognitive testing; critical period; genetic approach; glial activation; gray matter; imaging study; improved; in vivo; knock-down; longitudinal positron emission tomography; mouse model; neurobehavioral; neuroimaging; neuroinflammation; neurovascular; new therapeutic target; novel; novel marker; optical imaging; overexpression; pharmacologic; prevent; radioligand; radiotracer; response; scale up; sensory stimulus; single-cell RNA sequencing; tractography; transcriptome; transcriptomics; two-photon; uptake; vascular cognitive impairment and dementia; white matter; white matter injury

PROJECT SUMMARY: Microglia, the brain’s resident immune cells, are implicated in the pathophysiology of chronic ischemic cerebral small vessel disease (CSVD) and vascular cognitive impairment (VCI), a clinically important cause of dementia that preferentially affects white matter (WM). Colony stimulating factor 1 receptor (CSF1R) is a key regulator of myeloid lineage cells. Genetic loss of CSF1R blocks the normal population of resident microglia and systemic treatment with CSF1R antagonists such as PLX5622 results in a marked depletion of microglia in the CNS. Here we propose to evaluate the role of microglia and CSF1R signaling in a novel rodent model of CSVD/VCI developed in the laboratory of our colleague Dr. Edith Hamel (McGill University). Mice overexpressing transforming growth factor-beta1 (TGFOE) and fed a high cholesterol diet (HCD) display impaired cerebrovascular reactivity, diffuse leukoencephalopathy, and cognitive dysfunction that resembles human CSVD/VCI. We will first assess effects of TGFOE and HCD on regional and cell type specific gene expression in microglia and other myeloid cells using single cell RNA sequencing. Next we will determine if treatment with PLX5622 influences neurological, neuroimaging, and/or neurovascular outcomes in TGFOE mice (+/-HCD). We will assess longitudinal WM integrity outcomes using state-of- the-art 14 Tesla MRI with diffusion tensor imaging (DTI) and quantitative tractography. We will also use sophisticated assessments of resting-state functional connectivity (optical imaging of intrinsic signals) and neurocognition. Furthermore, we will perform longitudinal 2-photon brain imaging studies to track changes in the cerebrovasculature during critical periods of CSVD/ VCI disease initiation and progression. We will confirm the microglia-specific nature of our findings using an orthogonal genetic approach by crossing TGFOE mice with a Csf1rflox/flox : HexbCreERT2 bigenic line that exhibits stable, microglia-specific knockdown of Csf1r. We will then feed the trigenic TGFOE : Csf1rflox/flox : HexbCreERT2 line HCD and carry out the same comprehensive set of longitudinal parameters described above. We anticipate that both pharmacologic depletion of microglia and genetic deletion of CSF1R signaling specifically in microglia will attenuate WM inflammation and injury and result in improvement in multiple outcome parameters. In aim 3 we will collaborate with our colleagues in Radiology to use a novel CSF1R radioligand to carry out longitudinal positron emission tomography (PET) on TGFOE mice (+/-HCD) at multiple time points during disease initiation and progression. This will provide critical information on temporal and spatial in vivo expression patterns of CSF1R in the context of CSVD/VCI and generate foundational data for a novel biomarker for neuroinflammation that can be readily scaled up from mouse to humans. Overall, this microglia- and CSF1R signaling-targeted, WM-centric approach will provide important mechanistic information on the pathogenesis of ischemic WM injury in CSVD/VCI and elucidate new potential diagnostic and therapeutic approaches.

项目摘要：小胶质细胞是大脑的常驻免疫细胞，与以下疾病的病理生理学有关 慢性缺血性脑小血管病（CSVD）和血管性认知障碍（VCI）是临床上常见的疾病 痴呆症的重要原因，优先影响白质（WM）。集落刺激因子1受体 (CSF1R) 是骨髓谱系细胞的关键调节因子。 CSF1R 的遗传缺失阻碍了正常群体 驻留小胶质细胞和 CSF1R 拮抗剂（如 PLX5622）的全身治疗可导致显着的 中枢神经系统中小胶质细胞的耗竭。在这里，我们建议评估小胶质细胞和 CSF1R 信号传导的作用 我们的同事 Edith Hamel 博士的实验室开发了一种新型 CSVD/VCI 啮齿动物模型 （麦吉尔大学）。过度表达转化生长因子-β1 (TGFOE) 并喂食高胆固醇的小鼠 饮食（HCD）显示脑血管反应性受损、弥漫性白质脑病和认知功能障碍 类似于人类 CSVD/VCI。我们将首先评估 TGFOE 和 HCD 对区域和细胞类型的影响 使用单细胞 RNA 测序在小胶质细胞和其他骨髓细胞中进行特定基因表达。接下来我们将 确定 PLX5622 治疗是否影响神经学、神经影像学和/或神经血管 TGFOE 小鼠的结果 (+/-HCD)。我们将使用现状评估纵向 WM 完整性结果 最先进的 14 特斯拉 MRI，具有扩散张量成像 (DTI) 和定量纤维束成像。我们还将使用 静息态功能连接的复杂评估（内在信号的光学成像）和 神经认知。此外，我们将进行纵向 2 光子脑成像研究来跟踪 CSVD/VCI 疾病发生和进展关键时期的脑血管系统。我们将 使用正交遗传方法通过交叉证实我们的发现的小胶质细胞特异性 具有 Csf1rflox/flox 的 TGFOE 小鼠：HexbCreERT2 双基因系，表现出稳定的小胶质细胞特异性敲低 Csf1r。然后，我们将喂养三基因 TGFOE：Csf1rflox/flox：HexbCreERT2 系 HCD 并进行相同的操作 上述综合纵向参数集。我们预计这两种药理学 小胶质细胞的耗竭和小胶质细胞中 CSF1R 信号传导的基因删除将减弱 WM 炎症和损伤，并导致多个结果参数的改善。在目标 3 中，我们将合作 与放射科的同事一起使用新型 CSF1R 放射性配体进行纵向正电子 在疾病发生期间的多个时间点对 TGFOE 小鼠 (+/-HCD) 进行发射断层扫描 (PET) 进展。这将提供有关体内时间和空间表达模式的关键信息 CSF1R 在 CSVD/VCI 的背景下，并为新型生物标志物生成基础数据 神经炎症很容易从小鼠扩展到人类。总体而言，这种小胶质细胞和 CSF1R 以信号传导为目标、以 WM 为中心的方法将提供有关疾病发病机制的重要机制信息 CSVD/VCI 中的缺血性 WM 损伤并阐明新的潜在诊断和治疗方法。