Diverse Homeostatic Roles for Distinct Macrophages in the Developing Lung Vasculature

不同巨噬细胞在发育中的肺血管系统中的多种稳态作用

基本信息

批准号：
10362528
负责人：
Cristina Maria Alvira
金额：
$ 64.66万
依托单位：
STANFORD 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：
2021-03-05 至 2025-02-28
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10362528
关键词：
Acute Adult Air Sacs Alveolar Alveolar Macrophages Alveolus Anastomosis - action Area Basement membrane Birth Blood Vessels Bronchopulmonary Dysplasia Cell Communication Cells Chronic Complex Complication Coronary artery Cues Data Data Set Development Disease Distal Embryo Embryonic Development Endothelial Cells Epithelial Cells Exhibits Gases Gene Expression Genes Genetic Transcription Growth Heart Heterogeneity Hyperoxia Image Immune Immunity Impairment In Situ In Situ Hybridization In Vitro Infant Injury Knockout Mice Life Ligands Location Lung Lung diseases Mediating Molecular Myofibroblast Natural Immunity Natural regeneration Neuropeptides Organ Pathway interactions Pattern Phenotype Physiological Play Population Premature Birth Process Pulmonary Circulation Recovery Resolution Retina Role Serine Proteinase Inhibitors Signal Pathway Signal Transduction Smooth Muscle Myocytes Spatial Distribution Surface Testing Tissues Transgenic Organisms Translating Vascular Permeabilities Vascular Smooth Muscle Vascular remodeling Vascularization angiogenesis arteriole blood vessel development chemokine conditional knockout genetic signature hindbrain in vivo injury recovery lung development macrophage mouse model novel strategies postnatal postnatal development pulmonary function rapid growth receptor recruit repaired single-cell RNA sequencing therapeutic development transcriptomics

项目摘要

Alveolarization, the final stage of lung development occurring primarily postnatally, markedly increases gas exchange surface area. Rapid growth of the pulmonary vasculature by angiogenesis during early alveolarization drives distal lung growth, and disrupted angiogenesis impairs alveolarization. In other organs, specialized macrophages support angiogenesis by promoting blood vessel formation, providing survival and migratory cues to EC, and facilitating vascular anastomoses. However, the role of macrophages in the developing pulmonary vasculature remains entirely unknown. We recently embarked on a project employing single cell RNA-sequencing to define macrophage diversity during late embryonic and early postnatal lung development. Macrophages are extremely heterogenous with diverse phenotypes that are lineage- and tissue- specific, and highly influenced by the microenvironment. Preliminary data in this proposal demonstrate a tremendous increase in macrophage diversity after birth. Specialized, highly proliferative macrophages present before birth are replaced after birth by a complex and dynamic mixture of diverse macrophage subtypes exhibiting unique gene signatures, developmental gradients in gene expression, and specific locations within the lung suggesting distinct functions in tissue remodeling, angiogenesis, and immunity. Interestingly, a subset of embryonic macrophages was found to completely encircle small arterioles and express numerous genes that regulate lung branching, angiogenesis, and EC phenotype. After birth, these cells transitioned to an intermediate subset present only during the first few weeks of postnatal life that expressed additional tissue remodeling genes. Taken together, our data suggest the hypothesis that distinct macrophage populations support alveolarization by regulating pulmonary vascular development through the expression of factors that influence vascular growth and remodeling, which will be tested through three specific aims. Aim 1 will combine multiplexed in situ hybridization, lineage tracing, studies in primary EC and macrophages, and advanced imaging in transgenic and knock-out mice to define the role of specific macrophage subsets in modulating EC phenotype and regulating lung parenchymal and vascular growth. Aim 2 will utilize multiplexed in situ hybridization, conditional knock out mouse models, and ligand-receptor profiling of single cell datasets from pulmonary EC and macrophages to probe pathways mediating macrophage-EC communication. Finally, Aim 3 will determine if chronic hyperoxia alters diversity and phenotype of the lung macrophages during acute injury and after recovery, and specifically impairs developmental and homeostatic functions of lung macrophages. The successful completion of these studies will provide a multifaceted view of the diverse functions of lung macrophages during embryonic and early postnatal development at single cell resolution, and identify new pathways that could be directly translated into novel strategies to modulate vascular growth and regeneration in diseases marked by impaired pulmonary angiogenesis.

肺泡化是肺发育的最后阶段，主要发生在出生后，显着增加气体交换表面积。早期血管生成导致肺血管系统快速生长肺泡化驱动远端肺生长，血管生成中断会损害肺泡化。在其他器官中，专门的巨噬细胞通过促进血管形成来支持血管生成，提供生存和 EC 的迁移线索，并促进血管吻合。然而，巨噬细胞在发育中的肺血管系统仍然完全未知。我们最近开始了一个项目，雇用单细胞 RNA 测序确定胚胎晚期和产后早期肺巨噬细胞多样性发展。巨噬细胞具有极其异质性，具有谱系和组织不同的表型具有特定性，且受微环境影响较大。该提案中的初步数据表明出生后巨噬细胞多样性急剧增加。存在专门的、高度增殖的巨噬细胞出生前的巨噬细胞在出生后被不同巨噬细胞亚型的复杂且动态的混合物所取代表现出独特的基因特征、基因表达的发育梯度以及体内的特定位置肺表明在组织重塑、血管生成和免疫方面具有不同的功能。有趣的是，其中一个子集人们发现胚胎巨噬细胞完全包围小动脉并表达许多基因调节肺分支、血管生成和 EC 表型。出生后，这些细胞转变为中间细胞子集仅在出生后的最初几周内出现，表达额外的组织重塑基因。综上所述，我们的数据表明了这样的假设：不同的巨噬细胞群支持肺泡化通过影响血管生长的因子的表达来调节肺血管发育和改造，将通过三个具体目标进行测试。目标 1 将在原位组合多路复用杂交、谱系追踪、原代 EC 和巨噬细胞研究以及转基因和敲除小鼠以确定特定巨噬细胞亚群在调节 EC 表型和调节肺中的作用实质和血管生长。目标 2 将利用多重原位杂交、条件敲除小鼠肺内皮细胞和巨噬细胞的模型和单细胞数据集的配体-受体分析，以探测途径介导巨噬细胞-EC 通讯。最后，目标 3 将确定慢性高氧是否会改变多样性和急性损伤期间和恢复后肺巨噬细胞的表型，特别是损害肺巨噬细胞的发育和稳态功能。这些研究的成功完成将提供胚胎期和产后早期肺巨噬细胞多种功能的多方面观点以单细胞分辨率进行开发，并确定可直接转化为新型药物的新途径在以肺功能受损为特征的疾病中调节血管生长和再生的策略血管生成。