Meningeal Mast Cells: Key effectors of stroke pathology

脑膜肥大细胞：中风病理学的关键效应器

• 批准号: 8623155
• 负责人: GARY K STEINBERG
• 金额: $ 23.37万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-03-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8623155
• 关键词: Address; Adverse effects; Affect; Brain; Brain Edema; Brain Injuries; Brain Pathology; C5a anaphylatoxin receptor; Cell physiology; Cells; Complement; Data; Development; Diphtheria Toxin; Disease; Drug Targeting; Effector Cell; Encephalitis; Engraftment; Enzymes; Event; Evolution; Fc Receptor; Goals; IL6 gene; Immune; Immunotherapy; In Vitro; Inflammation; Inflammatory; Injection of therapeutic agent; Intrathecal Injections; Knock-in Mouse; Knockout Mice; Lesion; Measures; Mediating; Mediator of activation protein; Meningeal; Meninges; Modeling; Molecular; Molecular Mechanisms of Action; Mus; Outcome; Pathology; Pathway interactions; Play; Process; Recovery; Relative (related person); Reporting; Role; Site; Spleen; Stroke; Surface; Testing; Therapeutic; Tissues; Transgenic Mice; Wild Type Mouse; cytokine; diphtheria toxin receptor; disability; effective therapy; gain of function; immunoregulation; improved; injured; innovation; loss of function; mast cell; mast cell protease 4; mouse model; neutrophil; new therapeutic target; novel; novel therapeutics; post stroke; public health relevance; receptor; repaired; response; selective expression; therapeutic target; tool

DESCRIPTION (provided by applicant): Stroke, a leading cause of serious long-term disability in the US, is in need of therapeutics that reduce damage and promote recovery. Post-stroke inflammation is a critical determinant of damage and recovery and is thus a promising therapeutic target. Mast cells (MCs), which play critical roles in the development of inflammatory processes in other pathologies, were recently ascribed a role in the exacerbation of post-stroke brain inflammation and damage. This suggests that MCs could be key determinants of stroke-induced inflammation and hence are an attractive therapeutic target. The primary focus of this proposal is to elucidate the mechanism of action of mast cells in exacerbating stroke pathology, with the long-term goal of identifying novel therapeutic strategies for stroke. Our overall hypothesis is that mast cells residing in the meninges are key effectors of stroke pathology. This is tested in Aim 1 using two different approaches. The gain-of-function approach (Aim 1a) uses a "mast cell knock-in mouse" model in which the MC-deficiency of genetically MC- deficient mice is selectively repaired by engraftment of in vitro grown mast cells. Direct engraftment of MCs into the meninges of these MC-deficient mice will determine the involvement of meningeal-located MCs in stroke pathology. This is complemented by the loss-of-function approach (Aim1b) where meningeal MCs are depleted by meningeal injection of diphtheria toxin (DT) into a novel mouse model that selectively expresses the DT receptor on MCs. Together, innovative use of these mouse models enables us to determine if meningeal MCs are necessary and sufficient for the detrimental effects of MCs after stroke. Aim 2 addresses the molecular mechanism of action of MCs using the mast cell knock-in mouse model. Through engraftment of MCs from various receptor knock-out mice we will investigate the mechanism of meningeal MC activation (Aim 2a), and by engraftment of MCs from cytokine knock-out mice we will identify mast cell-secreted factors important for the downstream effects of MCs on stroke pathology (Aim 2b). Identifying a crucial role for meningeal MCs after stroke will highlight the importance o the meninges in modulating brain pathology. As the meninges are relatively accessible (e.g., by intrathecal injection) this concept could potentially present a new strategy for stroke therapeutic that may overcome the hurdle of targeting drugs to the injured brain and reduce unwanted side effects of systemic immunomodulation. Furthermore, by establishing the mechanism of action of MCs we begin to delineate the molecular pathways involved in modulating the response to stroke, an essential step to finding novel therapeutic targets. Together, our proposed studies address significant gaps in the understanding of post-stroke inflammatory events that contribute to stroke pathology and may identify new strategies for stroke therapeutics.

描述（由申请人提供）：中风是美国严重长期残疾的主要原因，需要减少损害并促进康复的治疗剂。中风后炎症是损害和恢复的关键决定因素，因此是一个有希望的治疗靶标。肥大细胞（MCS）在其他病理学中在炎症过程的发展中起着关键作用，最近在加剧后冲程后脑炎症和损伤中扮演了作用。这表明MC可以是中风引起的炎症的关键决定因素，因此是一个有吸引力的治疗靶标。该提案的主要重点是阐明肥大细胞在加剧卒中病理学中的作用机理，其长期目标是确定中风的新型治疗策略。我们的总体假设是，驻留在脑膜中的肥大细胞是中风病理学的关键效应因子。使用两种不同的方法在AIM 1中测试了这一点。功能收益方法（AIM 1A）使用“肥大细胞敲入小鼠”模型，其中通过植入体外种植的肥大细胞的植入来选择性地修复遗传缺陷小鼠的MC缺乏。将MC直接植入这些MC缺陷型小鼠的脑膜中，将确定脑膜化的MC在中风病理学中的参与。这是通过功能丧失方法（AIM1B）补充的，在这种方法中，脑膜MC被脑膜注射白喉毒素（DT）耗尽为一种新型的小鼠模型，该模型有选择地表达MCS上的DT受体。共同使用这些小鼠模型的创新使用使我们能够确定中风后MC的有害效果是否必要且足够。 AIM 2使用肥大细胞敲入小鼠模型解决了MC的分子机理。通过植入各种受体敲除小鼠的MC，我们将研究脑膜MC激活的机制（AIM 2A），并通过细胞因子敲除小鼠的MC植入MC，我们将确定对桅杆细胞分泌的因素，对下游效应很重要中风病理学的MC（AIM 2B）。识别中风后脑膜MC的关键作用将突出脑膜在调节脑病理学中的重要性。由于脑膜相对易于获取（例如，通过鞘内注射），该概念可能会呈现出中风治疗的新策略，该策略可能克服将药物靶向受伤的大脑的障碍，并减少全身免疫调节的不必要的副作用。此外，通过建立MC的作用机理，我们开始描述调节中风反应的分子途径，这是寻找新型治疗靶标的必不可少的步骤。我们提出的研究共同解决了有助于中风病理学的势头炎症事件的明显差距，并可能确定了中风治疗的新策略。