Determining the role of macrophages in the developing cardiac conduction system

确定巨噬细胞在心脏传导系统发育中的作用

基本信息

批准号：
10395422
负责人：
Shannon Elizabeth Paquette
金额：
$ 4.68万
依托单位：
BROWN UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-01-01 至 2023-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10395422
关键词：
Ablation Address Adult Affect Arrhythmia Attention Autonomic nervous system Calcium Calcium Signaling Cardiac Cardiac Myocytes Cardiac conduction system Cardiac development Cardiac health Cardiovascular system Cells Complex Computers and Advanced Instrumentation Connexin 43 Connexins Data Development Echocardiography Economic Burden Electric Stimulation Electrocardiogram Embryo Embryo Loss Embryonic Development Embryonic Heart Fellowship Fetal Heart Goals Health Heart Heart Abnormalities Heart Atrium Heart Diseases Heart Rate Homeostasis Image Immune Infection Inherited Institution Ion Channel Gating Ions Knowledge Larva Longevity Lung Maintenance Mediating Medical Mentorship Microscopy Modeling Morbidity - disease rate Morphology Mus Myocardial dysfunction Myocardium Natural regeneration Nodal Optics Organ Pattern Periodicity Pharmaceutical Preparations Physiology Regulation Reporting Research Resolution Risk Role Sentinel Series Short QT syndrome Signal Transduction Stress Stretching System Taxes Techniques Time Tissues Transgenic Organisms Universities Ventricular Work Zebrafish atrioventricular node calcium indicator cardiogenesis cell type cellular targeting constriction coronary vasculature electrical potential experience experimental study fetal genetic manipulation heart function immunoregulation in vivo insight light gated macrophage mutant new therapeutic target novel novel therapeutic intervention optogenetics response response to injury

项目摘要

PROJECT SUMMARY/ABSTRACT Macrophages are well-characterized as sentinel immune cells that coordinate cellular responses to injury and infection. However, emerging evidence demonstrates that macrophages have novel, non-canonical functions critical for developmental regulation, tissue homeostasis, and regeneration. Likewise, cardiac macrophages have essential functions in patterning the coronary vasculature, valvular remodeling, and in modulating adult heart conduction. Considering the substantial morbidity and economic burden associated with abnormal cardiogenesis and arrhythmias, further elucidating the roles of cardiac macrophages in normal heart development and function is critical for devising novel therapeutic strategies. In adult mammalian hearts, macrophages electrically couple to cardiomyocytes at the atrioventricular node via Connexin 43, a gap junction protein. These macrophages directly modulate electrical activity of nodal cardiomyocytes, and thus cardiac conduction. However, it is not known if macrophages (1) are required during embryogenesis to establish proper conduction or (2) if macrophage-derived signals modulate heart function in the developing heart. Therefore, this proposal will address a critical knowledge gap in the field of cardiac development in two aims. In Aim 1, I will establish the electrical potential of embryonic macrophages to modulate fetal cardiac conduction. In Aim 2, I will determine how loss of embryonic macrophage affects conduction and adult heart health. In my approach, I utilize zebrafish, a well-established developmental model whose salient features include rapid ex vivo development, optical transparency, and high amenability to genetic manipulation. This proposal will be carried out at Brown University, an exemplar academic research institution with extensive access to advanced instrumentation. With the guidance and mentorship of her sponsor, Dr. Jessica Plavicki, and co-sponsor, Dr. Chris Moore, the applicant is prepared and equipped to carryout this fellowship. My exciting preliminary data reveal previously undescribed roles of macrophages in embryonic cardiac conduction and cardiogenesis. Using transgenic zebrafish with macrophage-specific expression of a genetically encoded calcium indicator, GCaMP6s, I found that seeded macrophages have synchronous bursts of calcium activity in time with ventricular beating. In optogenetic experiments, I show that larval heart rate can be modulated by stimulating or silencing macrophage electrical activity via macrophage-specific expression of light-gated ion channels. This poses an intriguing question of whether developmental arrythmias could be corrected by specifically targeting macrophages. Loss of embryonic macrophages, via drug-inducible ablation or in embryonic macrophage mutants, altered ventricular chamber formation and function in embryonic zebrafish, as well as adult cardiomyocyte compaction and gross heart morphology. Successful completion of this fellowship will clarify and expand our knowledge of non-canonical macrophage functions in the developing heart, as well as provide valuable insight into the cell types modulating embryonic heart function.

项目概要/摘要巨噬细胞是协调细胞对损伤反应的前哨免疫细胞和感染。然而，新出现的证据表明巨噬细胞具有新颖的、非典型的对发育调节、组织稳态和再生至关重要的功能。同样，心脏巨噬细胞在构建冠状脉管系统、瓣膜重塑和调节成人心脏传导。考虑到与此相关的巨大发病率和经济负担心脏发生异常和心律失常，进一步阐明心脏巨噬细胞在正常心脏中的作用发育和功能对于设计新的治疗策略至关重要。在成年哺乳动物心脏中，巨噬细胞与房室结处的心肌细胞电耦合通过间隙连接蛋白 Connexin 43。这些巨噬细胞直接调节节点的电活动心肌细胞，从而产生心脏传导。然而，尚不清楚巨噬细胞 (1) 在胚胎发生以建立适当的传导或（2）巨噬细胞衍生的信号是否调节心脏功能正在发育的心脏。因此，该提案将解决心脏领域的关键知识差距两个目标的发展。在目标 1 中，我将建立胚胎巨噬细胞调节的电位胎儿心脏传导。在目标 2 中，我将确定胚胎巨噬细胞的损失如何影响传导和成人心脏健康。在我的方法中，我利用斑马鱼，这是一种成熟的发育模型，其显着特征其特点包括快速的离体发育、光学透明性和对基因操作的高度适应性。该提案将在布朗大学进行，布朗大学是一所具有广泛研究成果的模范学术研究机构。获得先进的仪器。在她的赞助商 Jessica Plavicki 博士的指导和指导下，共同发起人克里斯·摩尔博士表示，申请人已准备好并有能力开展这项研究金。我令人兴奋的初步数据揭示了巨噬细胞在胚胎心脏中以前未描述的作用传导和心脏发生。使用具有巨噬细胞特异性表达基因的转基因斑马鱼编码的钙指示剂，GCaMP6s，我发现种子巨噬细胞具有同步的钙爆发活动与心室搏动同步。在光遗传学实验中，我证明幼虫心率可以调节通过光门控离子的巨噬细胞特异性表达刺激或沉默巨噬细胞电活动渠道。这就提出了一个有趣的问题：发育性心律失常是否可以通过以下方法纠正：专门针对巨噬细胞。通过药物诱导消融或在胚胎中损失胚胎巨噬细胞巨噬细胞突变体，改变胚胎斑马鱼以及成年斑马鱼的心室形成和功能心肌细胞压实和大体心脏形态。成功完成本次研究金将澄清并扩展我们对发育中心脏中非典型巨噬细胞功能的了解，并提供对调节胚胎心脏功能的细胞类型有宝贵的见解。