Molecular mechanisms regulating leukocyte trafficking

调节白细胞运输的分子机制

• 批准号: 9890986
• 负责人: Matthias Majetschak
• 金额: $ 18.69万
• 依托单位: UNIVERSITY OF SOUTH FLORIDA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-03-11 至 2022-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9890986
• 关键词: Adrenergic Agents; Adrenergic Receptor; Affect; Autoimmune Diseases; Bioluminescence; CXCR; CXCR4 Receptors; CXCR4 gene; Catecholamines; Cell Line; Cell surface; Cells; Chemotaxis; Complex; Data; Development; Disease; Energy Transfer; Exploratory/Developmental Grant; Family; G-Protein-Coupled Receptors; GTP-Binding Proteins; Health; Human; IL8RB gene; Immune; Immune system; Infection; Inflammation; Innate Immune System; Interleukin-8B Receptor; Lead; Leukocyte Trafficking; Leukocytes; Malignant Neoplasms; Mediating; Modeling; Molecular; Molecular Biology; Molecular Target; Mus; Nervous system structure; Patients; Pattern; Peripheral Blood Mononuclear Cell; Peritonitis; Pharmacology; Play; Population; Process; Prostate; Protein Family; Receptor Signaling; Recombinants; Regulation; Rodent; Role; Series; Signal Transduction; Smooth Muscle; Smooth Muscle Myocytes; Stress; System; Testing; Transmembrane Domain; Vascular Smooth Muscle; cell motility; chemokine; chemokine receptor; experimental study; fighting; human migration; immune function; immunoregulation; in vivo; innate immune function; insight; member; migration; monocyte; receptor; receptor expression; receptor function; recruit; response; symposium; tissue injury; treatment strategy

Project Summary/Abstract The autonomous nervous system regulates innate immune functions during the stress or “fight and flight” response through the release of endogenous catecholamines, which activate the G protein-coupled receptor (GPCR) family of adrenergic receptors (ARs) expressed in the immune system. The roles of α1-ARs in the regulation of innate immune functions, however, are poorly understood and the molecular mechanisms underlying cross-talk between the neurohormonal and innate immune system remain to be determined. The family of chemokine receptors (CRs) is essential for the regulation of leukocyte recruitment and plays important roles in all aspects of inflammation and in numerous disease processes. Recently, we discovered that α1-ARs form hetero-oligomeric complexes with chemokine (C-X-C motif) receptor (CXCR) 4 and with atypical chemokine receptor (ACKR) 3, and that α1B-AR within heteromeric CXCR4:α1B-AR complexes regulates CXCR4-mediated migration of human vascular smooth muscle cells. It is unknown whether heteromeric complexes between CRs and α1-ARs exist in leukocytes. We observed in pilot experiments that hetero-oligomeric complexes between α1A/B/D-AR and CXCR4 are detectable on the cell surface of THP-1 cells and in freshly isolated human peripheral blood mononuclear cells. Furthermore, we performed preliminary intermolecular bioluminescence resonance energy transfer (BRET) experiments and detected that α1b-AR is able to form heteromeric complexes with multiple members of the CR family. This leads to our working hypothesis that the formation of hetero-oligomeric complexes between α1-ARs and CRs is a common molecular mechanism through which the neurohormonal system interacts with the innate immune system to regulate CR-mediated leukocyte trafficking in health and disease. To test this hypothesis, we will focus on monocytes as a major cell population in the innate immune system and on heteromers between CRs and α1B-AR to provide proof-of-concept. We propose the following specific aims: 1. To study the distribution and function of CR:α1B-AR heteromeric complexes in human monocytes. We will determine which CRs are able to form heteromers with α1B-AR, define the patterns of receptor heteromerization and assess the effects of receptor heteromerization on CR signaling and function. 2. To assess the roles of α1-ARs and of CR:α1B-AR heteromeric complexes in the regulation of monocyte recruitment during inflammation in vivo. Here we will utilize MacBlue mice in a peritonitis model to evaluate the roles of α1-ARs and CR:α1B-AR heteromers in the regulation of monocyte migration in inflammation. The proposed exploratory/developmental studies will provide the scientific basis to establish receptor heteromerization as a mechanism through which the neurohormonal system controls CR-mediated leukocyte trafficking. These data could lead to a paradigm shift in the understanding of the regulation of leukocyte recruitment and are expected to identify new molecular targets to modulate innate immune functions in numerous disease processes, which has the potential to facilitate the development of new treatment strategies for patients.

项目总结/摘要 自主神经系统在压力或“战斗和逃跑”期间调节先天免疫功能 通过释放内源性儿茶酚胺来激活G蛋白偶联受体 在免疫系统中表达的肾上腺素能受体（AR）的GPCR家族。α1-ARs在肿瘤发生中的作用 然而，对先天免疫功能的调节知之甚少， 神经激素和先天免疫系统之间潜在的相互作用仍有待确定。的 趋化因子受体（CRs）家族对于白细胞募集的调节是必需的，并且起重要作用 在炎症的各个方面和许多疾病过程中发挥作用。最近，我们发现α1-AR 与趋化因子（C-X-C基序）受体（CXCR）4和非典型趋化因子形成异源寡聚复合物 CXCR 4：α1B-AR复合物中的α1B-AR调节CXCR 4介导的 人血管平滑肌细胞的迁移。目前尚不清楚CR之间的异聚复合物是否 白细胞中存在α1-AR。我们在初步实验中观察到， α 1 A/B/D-AR和CXCR 4可在THP-1细胞的细胞表面和新鲜分离的人外周血中检测到 血单核细胞此外，我们进行了初步的分子间生物发光共振， 能量转移（BRET）实验，并检测到α1b-AR能够与 CR家族的多个成员。这导致我们的工作假设，异源寡聚体的形成 α1-AR和CRs之间的复合物是一种常见的分子机制，通过这种机制，神经激素 系统与先天免疫系统相互作用，以调节健康状况下CR介导的白细胞运输， 疾病为了验证这一假设，我们将重点放在单核细胞作为一个主要的细胞群体在先天免疫， 系统和CRs和α1B-AR之间的异聚体，以提供概念验证。我们提议下列 具体目标：1.研究CR：α1B-AR异聚体复合物在人体内的分布和功能 单核细胞我们将确定哪些CR能够与α1B-AR形成异聚体，定义 受体异聚化并评估受体异聚化对CR信号传导和功能的影响。2. 评价α1-AR和CR：α1B-AR异聚体复合物在单核细胞调节中的作用， 体内炎症过程中的募集。在这里，我们将利用MacBlue小鼠腹膜炎模型，以评估 α1-AR和CR：α1B-AR异聚体在炎症单核细胞迁移调节中的作用。的 拟议的探索性/开发性研究将为建立受体提供科学依据。 异聚化作为神经激素系统控制CR介导的白细胞的机制 贩卖人口这些数据可能会导致对白细胞调节的理解发生范式转变， 招募，并预计将确定新的分子靶点，以调节先天免疫功能，在许多 疾病过程，这有可能促进为患者开发新的治疗策略。