Macrophage Activation & Substance P Receptor Expression

描述（由申请方提供）：P物质是一种神经肽，可影响外周组织和中枢神经系统中的宿主反应。因此，P物质及其受体，神经激肽-1受体，代表了神经和免疫系统之间最重要的联系之一。神经免疫相互作用将是本提案的重点，其总体目标是明确定义神经激肽-1受体用于增强宿主对病原体的反应的机制。这些研究将利用体内和体外感染模型，重点研究巨噬细胞、树突状细胞和小胶质细胞，以及神经肽P物质如何增强宿主来源或病原体来源的信号。神经激肽-1受体缺陷小鼠的使用将提供一个有价值的体内模型系统，以确定在宿主反应的差异相比，同源，野生型小鼠品系。细菌和病毒病原体将被用来定义在体内机制介导的P物质结合神经激肽-1受体。这些机制将集中在宿主反应的启动以及抗原特异性反应的发展上。研究还将侧重于P物质对抗原加工/呈递和巨噬细胞和树突细胞上神经激肽-1受体介导的共刺激的影响，作为调节宿主反应的机制。在体外培养的原代脑小胶质细胞将研究其对P物质的反应。此外，小胶质细胞培养将被用来质疑是否可以定义神经激肽-1受体介导的机制，这可能有助于解释中枢神经系统内神经肽介导的炎症反应。将用于这些研究的方法包括核糖核酸酶保护测定、T-PER匀浆中存在的分子的酶联免疫吸附测定、免疫荧光染色细胞的流式细胞术分析和已进行三色染色以鉴定表达分子的细胞来源的组织切片的共聚焦分析。遗传缺陷和转基因小鼠也将用作定义P物质介导的应答的模型。总之，这些研究将证明P物质是宿主对病原体免疫反应的组成部分。

DESCRIPTION (provided by applicant): Substance P is a neuropeptide that can affect host responses in peripheral tissues and in the central nervous system. As such, substance P and its receptor, the neurokinin-1 receptor, represent one of the most important links between the nervous and immune systems. Neuro-immunological interactions will be the focus of this proposal, with the overall goal of clearly defining the mechanisms used by neurokinin-1 receptors to augment the host response against pathogens. These investigations will make use of in vivo and in vitro models of infection, and focus on macrophages, dendritic cells, and microglia, and how the neuropeptide substance P can augment host-derived or pathogen-derived signals. The use of neurokinin-1 receptor-deficient mice will provide a valuable in vivo model system to define differences in the host responses when compared to congenic, wild-type mouse strains. Bacterial and viral pathogens will be used to define in vivo mechanisms mediated by substance P binding to neurokinin-1 receptors. Such mechanisms will focus on the initiation of host responses, as well as the development of antigen-specific responses. Studies will also focus on the effects of substance P on antigen processing/presentation and co-stimulation mediated by neurokinin-1 receptors on macrophages and dendritic cells as a mechanism for modulating the host response. In vitro cultures of primary brain microglia will be investigated for their responsiveness to substance P. In addition, microglia cultures will be used to question whether neurokinin-1 receptor-mediated mechanisms can be defined which might help to explain neuropeptide-mediated inflammatory responses within the central nervous system. The methods which will be used in these studies include ribonuclease protection assays, enzyme-linked immunosorbent assays of molecules present in T-PER homogenates, flow cytometric analyses of immunofluorescently stained cells, and confocal analyses of tissue sections which have been tri-color stained to identify the cellular source of expressed molecules. Genetically deficient and transgenic mice will also be used as models for defining substance P mediated responses. Taken together, these studies will demonstrate that substance P is an integral part of the host immune response against pathogens.