Interplay between meningeal lymphatics, high-density lipoproteins and border macrophages in cerebral amyloid angiopathy

脑淀粉样血管病中脑膜淋巴管、高密度脂蛋白和边界巨噬细胞之间的相互作用

• 批准号: 10674681
• 负责人: Gwendalyn J Randolph
• 金额: $ 57.84万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10674681
• 关键词: ATP binding cassette transporter 1; Address; Affect; Alzheimer' s Disease; Amyloid beta-Protein; Behavior; Bile fluid; Blood; Blood Circulation; Blood Vessels; Blood flow; Brain; Cell membrane; Cells; Cerebral Amyloid Angiopathy; Cerebral hemisphere hemorrhage; Cholesterol; Chronic; Coupling; Data; Dendritic Cells; Deposition; Disease; Disease Progression; Endocytosis; Experimental Models; Genetic; Health; High Density Lipoproteins; Hour; Human; Image; Impairment; Investigational Therapies; Knock-in Mouse; Laboratories; Leptomeninges; Lesion; Light; Link; Lipoproteins; Liquid substance; Literature; Liver; Lymph; Lymphatic; Macrophage; Mediating; Mediator; Membrane Transport Proteins; Meningeal; Meningeal lymphatic system; Meninges; Modeling; Mus; Natural Immunity; Organ; Penetration; Peptides; Phagocytosis; Phenotype; Plasma; Process; Proteins; Role; Signal Transduction; Site; Testing; Therapeutic Intervention; Thinness; Tissues; Tunica Adventitia; Vascular Diseases; abeta deposition; apolipoprotein E-4; arteriole; blood-brain barrier crossing; brain parenchyma; confocal imaging; cranium; epidemiology study; improved; interest; interstitial; intravital imaging; lymph flow; lymphatic circulation; lymphatic vasculature; monocyte; mouse model; neuroimmunology; porcine model; restraint; reverse cholesterol transport; spatial relationship; tool; trafficking; two-photon; vascular inflammation; β-amyloid burden

ABSTRACT – project 3 The Randolph lab studies vascular inflammation and has a long-standing interest in the egress of cells and molecules that impact chronic vascular diseases. With a track record in studying the trafficking of monocytes (and the cells they become), we later began studying the transit of apoA1-enriched high-density lipoprotein (HDLA1) through tissues. We demonstrated that liver-derived HDLA1 leaves most tissue parenchyma through lymphatics to mediate reverse cholesterol transport, a process whereby cholesterol from cells in various body organs is picked up by HDLA1 and returned to the liver for disposal in bile. Reverse cholesterol transport regulates macrophage phenotype in various diseases, as macrophages readily accumulate cholesterol. On the other hand, macrophages also efficiently transfer cholesterol to HDLA1 via the membrane transporter ABCA1 in a process called cholesterol efflux. If cholesterol efflux is impaired, for example from reduction of HDLA1, cholesterol accumulates in signaling domains at the plasma membrane to affect the phenotype and activation status of macrophages. Overall, macrophages and lymphatics provide two distinct means for tissue clearance of metabolites, debris, and other mediators--one via endocytosis or phagocytosis and the other via fluid transport--and HDLA1 bridges these mechanisms. We have developed and validated a knock-in mouse line expressing photoactivatable GFP linked to apoA1, to quantitatively track endogenous HDLA1 after photo- activating a tissue of interest. Although little HDLA1 crosses the blood-brain barrier to enter the brain, HDLA1 enters the meningeal interstitium. Indeed, preliminary data reveal that the HDLA1 can be tagged by shining 405 nm light on the thinned skullbone as the HDLA1 passes through the meninges. Phototagged meningeal HDLA1 reaches the blood circulation one hour later, but only under conditions when the meningeal draining lymphatic vasculature is intact. Epidemiological studies in cerebral amyloid angiopathy (CAA), a disease broadly associated with Alzheimer’s disease (AD) and characterized by A deposition in the adventitia of the penetrating and meningeal arterioles, identify HDLA1 levels as inversely correlated with cerebral hemorrhage associated with CAA. A connection between HDLA1 and CAA is directly supported by genetic and experimental therapeutic interventions in mice. However, detailed mechanistic studies to unravel how HDLA1 affects CAA have not been conducted. Using the 5XE4fl/fl murine model of CAA developed by the Holtzman laboratory, we will herein focus on unraveling the role of HDLA1 in CAA by coupling use of our HDLA1 phototag tool with approaches to interrogate its connection to lymphatic and blood flow (aim 1), to monocyte/macrophage phenotype (aim 2), and to disease progression overall (aim 3). We here will test the hypothesis that HDLA1 restrains CAA and that its meningeal transit is impaired during CAA. By contrast, in states of health, we propose that it functionally maintains meningeal interstitial flow into lymphatics by interacting with and governing the phenotype of meningeal macrophages, including parenchymal border macrophages (PBM).

摘要-项目3 兰多夫实验室研究血管炎症，长期以来一直对细胞的排出感兴趣， 影响慢性血管疾病的分子。在研究单核细胞的运输方面有着良好的记录 (and之后，我们开始研究富含apoA 1的高密度脂蛋白的转运 （HDLA 1）通过组织。我们证明，肝源性HDLA 1通过 胆固醇逆向转运是一个过程，胆固醇从细胞在各种身体 器官被HDLA 1拾取并返回肝脏以在胆汁中处置。胆固醇逆向转运 调节各种疾病中的巨噬细胞表型，因为巨噬细胞容易积累胆固醇。上 另一方面，巨噬细胞也通过膜转运蛋白ABCA 1有效地将胆固醇转移到HDLA 1， 一个叫做胆固醇流出的过程如果胆固醇流出受损，例如HDLA 1减少， 胆固醇在质膜的信号传导域中积累，从而影响表型和活化 巨噬细胞的状态。总的来说，巨噬细胞和巨噬细胞提供了两种不同的组织清除方法 代谢物，碎片和其他介质-一种通过内吞作用或吞噬作用，另一种通过液体 运输-HDLA 1桥接这些机制。我们已经开发并验证了一种敲入小鼠系 表达与apoA 1连接的光活化GFP，以定量追踪光活化后的内源性HDLA 1。 激活感兴趣的组织。尽管很少的HDLA 1穿过血脑屏障进入大脑， 进入了脑膜脑膜鞘实际上，初步数据显示HDLA 1可以通过发光405标记 当HDLA 1穿过脑膜时，在变薄的颅骨上显示1.5nm的光。光标记脑膜HDLA 1 一小时后到达血液循环，但只有在脑膜引流淋巴管 血管系统完好脑淀粉样血管病（CAA）的流行病学研究， 与阿尔茨海默病（AD）相关，特征为血管外膜A β沉积， 穿透和脑膜小动脉，确定HDLA 1水平与脑出血呈负相关 与CAA有关。HDLA 1和CAA之间的联系直接受到遗传和实验的支持。 在小鼠中的治疗干预。然而，详细的机制研究，以解开HDLA 1如何影响CAA 尚未进行。使用Holtzman实验室开发的CAA的5XE 4fl/fl小鼠模型，我们 本文将通过结合使用我们的HDLA 1光标记工具与 询问其与淋巴和血流（aim 1），单核细胞/巨噬细胞 表型（目的2）和疾病总体进展（目的3）。我们在这里将测试假设，HDLA 1 抑制CAA，并且在CAA期间其脑膜运输受损。相反，在健康状态下，我们 提出它通过与淋巴管相互作用和相互作用，在功能上维持脑膜间质流入淋巴管 控制脑膜巨噬细胞的表型，包括实质边缘巨噬细胞（PBM）。