Ontogenetic niche of B cells at the CNS borders in homeostasis, aging and autoimmunity

CNS 边界 B 细胞在稳态、衰老和自身免疫中的个体发育生态位

基本信息

批准号：
10446266
负责人：
MARCO COLONNA
金额：
$ 62.45万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-02-01 至 2027-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10446266
关键词：
Age Aging Antigens Applications Grants Arachnoid mater Autoantigens Autoimmune Diseases Autoimmune Responses Autoimmunity B-Cell Activation B-Cell Antigen Receptor B-Cell Development B-Lymphocytes Behavioral Bioinformatics Blood Blood Circulation Blood Vessels Bone Marrow Bone Marrow Transplantation Brain CNS autoimmunity CXCL12 gene Calvaria Cell Compartmentation Cells Central Nervous System Diseases Cephalic Cerebrospinal Fluid Clone Cells Data Development Disease Dura Mater Environment Fibroblasts Gene Expression Gene Expression Profile Goals Grant Hematopoietic Homeostasis Homing Human Immune Immune Tolerance Immune system Immunoglobulins Immunologic Surveillance Invaded Knock-out Knockout Mice Knowledge Light Lupus Lymphocyte Lymphocytic Infiltrate MS4A1 gene Mature B-Lymphocyte Mediating Membrane Meningeal Meninges Minor Modeling Monoclonal Antibodies Multiple Sclerosis Mus Nervous system structure Neuraxis Neurologic Neurons Neuropsychiatric Systemic Lupus Erythematosus Parabiosis Pathogenicity Pathology Periosteum Peripheral Plasma Cells Plasmablast Play Publishing Reactive Plasma Cell Role Science Seminal Source Specificity Specimen Spinal Cord Spleen Subarachnoid Space Surface Syndrome Systemic Lupus Erythematosus Techniques Testing Tissues Treatment Efficacy Update Work aged autoreactive B cell autoreactivity base bone confocal imaging cranium experience experimental study flat bone follow-up human model lupus-like lymphoid organ mouse model neuroinflammation preservation reconstitution recruit response rituximab theories transcriptomics young adult

项目摘要

PROJECT SUMMARY B cells have an important pathogenic role in neurological autoimmune disorders, such as multiple sclerosis (MS) and neuropsychiatric systemic lupus erythematosus (NP-SLE), one of the most disabling manifestations of SLE. The relevance of B cells in central nervous system (CNS) autoimmunity is underscored by the therapeutic efficacy of mAb-mediated B cell depletion in MS. How autoreactive B cells are generated and infiltrate the CNS remains enigmatical. The CNS is enclosed within three membranes: pia, arachnoid, and dura. Between the arachnoid and pia lies the subarachnoid space, which contains cerebrospinal fluid that harbors assorted immune cells, including B cells. During neuroinflammation, blood lymphocytes infiltrate the meninges to mount local humoral and/or cellular responses. Thus, meningeal B cells are thought to exclusively derive from the systemic circulation. However, we recently showed that in young adult mice meningeal B cells mainly derive from the bone marrow of cranial flat bones, known as calvaria, through special vascular channels. During aging, in contrast, age-associated-B cells (ABC) migrate from the periphery into the dura, where they may differentiate into Ig- secreting plasma cells. We hypothesize that meningeal B cells that derive from calvaria and differentiate locally are tolerant to CNS-Ag. By contrast, B cells that originate from the periphery and hence are not educated by the local antigenic milieu, may differentiate into autoreactive plasma cells upon CNS-Ag encounter. In Aim 1, we will investigate mechanisms of meningeal B cell tolerance to local antigens under steady-state. Preliminary data suggest that self-Ag experience during B cell development induces meningeal B cell depletion. Alongside, we will examine meningeal B cell activation upon foreign Ag encounter. Finally, we will investigate the impact of the microenvironment in dura B cell development, focusing on CXCL12 produced by dura fibroblasts. In Aim 2, we will investigate autoreactivity of meningeal B cells and plasma cells in the SWAP-70/DEF6 double knock-out (DKO) model of lupus. Preliminary data show accumulation of plasmablasts in the meninges of DKO mice. We will compare the transcriptional profiles and B cell receptor (BCR) repertoires of B cells and plasma cells from the dura and spleen to determine whether systemic B cells clones disseminate equally in lymphoid organs and meninges, or whether the CNS environment recruits specific clones that further differentiate into plasma cells. In parallel, DKO mice will be examined for behavioral alterations and CNS pathology. We will also identify the utmost expanded BCR clones in the dura of DKO mice and generate monoclonal antibodies to ascertain specificity for autoantigens. In Aim 3, we will obtain a single-cell transcriptomic profile of human dura immune cells isolated from autoptic specimens, filling a critical gap in our knowledge of human meninges. Overall, this proposal will advance our understanding of B cells in the CNS and mechanisms that promote neuroinflammation. To achieve this, we will leverage the complementary expertise of the Colonna lab, which studies neuroinflammation, and the Pernis lab, which studies autoimmunity in both humans and mouse models.

项目概要 B 细胞在神经性自身免疫性疾病（例如多发性硬化症 (MS)）中具有重要的致病作用以及神经精神系统性红斑狼疮 (NP-SLE)，这是 SLE 中最严重的致残表现之一。治疗强调了 B 细胞在中枢神经系统 (CNS) 自身免疫中的相关性 mAb 介导的 B 细胞耗竭在 MS 中的功效。自身反应性 B 细胞如何产生并浸润中枢神经系统仍然是个谜。中枢神经系统被三层膜包围：软脑膜、蛛网膜和硬脑膜。之间蛛网膜和软脑膜位于蛛网膜下腔，其中含有具有各种免疫功能的脑脊液细胞，包括 B 细胞。在神经炎症期间，血液淋巴细胞浸润脑膜以附着在局部体液和/或细胞反应。因此，脑膜 B 细胞被认为完全源自全身系统。循环。然而，我们最近发现，在年轻成年小鼠中，脑膜 B 细胞主要来源于骨颅骨扁骨的骨髓（称为颅骨）通过特殊的血管通道。相比之下，在衰老过程中，年龄相关 B 细胞 (ABC) 从外周迁移到硬脑膜，在那里它们可能分化为 Ig- 分泌浆细胞。我们假设源自颅骨并局部分化的脑膜 B 细胞对 CNS-Ag 具有耐受性。相比之下，源自外周的 B 细胞因此不受外周细胞的教育。局部抗原环境，可能在 CNS-Ag 遇到时分化为自身反应性浆细胞。在目标 1 中，我们将研究稳态下脑膜 B 细胞对局部抗原的耐受机制。初步数据表明 B 细胞发育过程中的自身抗原经历会导致脑膜 B 细胞耗竭。旁边，我们将检查外来 Ag 遇到时脑膜 B 细胞的激活情况。最后，我们将调查该事件的影响硬脑膜 B 细胞发育中的微环境，重点关注硬脑膜成纤维细胞产生的 CXCL12。在目标 2 中，我们将研究 SWAP-70/DEF6 双敲除中脑膜 B 细胞和浆细胞的自身反应性 (DKO) 狼疮模型。初步数据显示 DKO 小鼠脑膜中存在浆母细胞积聚。我们将比较 B 细胞和浆细胞的转录谱和 B 细胞受体 (BCR) 库硬脑膜和脾脏以确定全身 B 细胞克隆是否在淋巴器官和脑膜，或者中枢神经系统环境是否招募进一步分化为浆细胞的特定克隆。在与此同时，DKO 小鼠将接受行为改变和中枢神经系统病理学检查。我们还将确定在 DKO 小鼠的硬脑膜中最大程度地扩增 BCR 克隆，并生成单克隆抗体来确定自身抗原的特异性。在目标 3 中，我们将获得人类硬脑膜免疫的单细胞转录组谱从自体光学标本中分离出的细胞，填补了我们对人类脑膜知识的一个关键空白。总体而言，这该提案将增进我们对 CNS 中 B 细胞和促进神经炎症机制的理解。为了实现这一目标，我们将利用 Colonna 实验室的互补专业知识，该实验室研究神经炎症，以及佩尼斯实验室，该实验室研究人类和小鼠模型的自身免疫。