CNS INFLAMMATION IN NERVOUS AND MENTAL DISEASE

神经和精神疾病中的中枢神经系统炎症

• 批准号: 2392989
• 负责人: Joel S Pachter
• 金额: $ 24.01万
• 依托单位: UNIVERSITY OF CONNECTICUT SCH OF MED/DNT
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-04-01 至 2000-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2392989
• 关键词: antibody; astrocytes; blood brain barrier; cell migration; central nervous system; chemoattractants; cytomegalovirus; electron microscopy; fluorescence microscopy; human tissue; inflammation; interferon gamma; interleukin 1; interleukin 2; leukocyte activation /transformation; lipopolysaccharides; monocyte; phorbols; tissue /cell culture; transforming growth factors; tumor necrosis factor alpha; vascular endothelium

Cells of the monocyte/macrophage lineage are now thought to be prominent effector cells that leave the circulation and play a pathogenetic role in several neurologic disorders that affect mental health status, including AIDS dementia complex, multiple sclerosis and Alzheimer's disease. However, little is known of the signals that promote the extravasation of monocytes through the restrictive blood-brain barrier (BBB), or the cells with which they interact once they enter the brain. To address these issues, a cell culture model of the human BBB will be used to analyze - for the first time - the distinct phases of monocyte migration through the BBB in response to a variety of stimuli. The long-term objective of this proposal is to test the hypothesis that monocyte migration across the BBB can be promoted by a variety of factors, e.g., specific cytokines, chemotaxins and other substances, which affect the activation state of either monocytes or brain microvessel endothelial cells (BMEC). Initial studies will assess the effects of monocyte stimulation/activation with lipopolysaccharide (LPS), phorbol myristate acetate (PMA) and interferon- gamma (IFN-gamma). These agents have been shown to promote monocyte adhesion to/migration across peripheral vasculature, but have yet to be analyzed with respect to monocyte interaction with the BBB. This is critical, as BBB endothelium may behave distinctively from that of peripheral vessels. Subsequent studies will analyze the role of endothelial stimulation/activation by LPS and cytokines tumor necrosis factor-alpha (TNF-alpha), IFN-gamma and interleukins-l and -2 (IL-1, IL-2) - substances again known to foster monocyte migration across the peripheral circulation, and which, in the case of the cytokines, have been shown to be up-regulated in the brain concurrent with monocytic infiltration. Combinations of monocyte/BMEC stimulation will also be performed to see if this further enhances monocyte migration. The effect of BMEC infection with cytomegalovirus (CMV) will be evaluated as well, as CMV infects BMEC in AIDS, and has been shown to augment monocyte adhesion to infected peripheral vessel endothelial cells. CMV may thus aid in recruiting monocytes to the brain. The effects of monocyte chemotactic peptides MCP-1 and TGF-beta will additionally be analyzed, as these may be released by astrocytes during CNS inflammatory disease, and could also foster monocyte trafficking to the brain. These studies will be performed in the presence and absence of astrocyte-conditioned media, as such media has been shown to influence BBB permeability and, consequently, glial- derived factors might influence monocyte migration. BBB integrity will be analyzed during the course of these studies by both electron and fluorescence microscopy, to determine whether monocyte migration requires or induces endothelial cell damage. Antibody "blocking" experiments will be also be performed to identify cell adhesion molecule:ligand pathways operant in monocyte migration across the BBB. Lastly, the effects of monocyte:astroglial interactions on monocyte migration across the BBB model will be evaluated as well. These experiments will illuminate factors that regulate monocyte entry into the brain, and thus identify potential targets for therapeutic intervention in a variety of crippling CNS diseases.

单核细胞/巨噬细胞谱系的细胞现在被认为是突出的 效应细胞，离开循环系统，并发挥致病作用， 影响心理健康状况的几种神经系统疾病，包括 艾滋病痴呆综合症，多发性硬化症和阿尔茨海默病。 然而，很少有人知道的信号，促进外渗， 单核细胞通过限制性血脑屏障（BBB），或细胞 一旦它们进入大脑就会与之相互作用。解决这些 问题，人血脑屏障的细胞培养模型将用于分析- 第一次-单核细胞迁移的不同阶段，通过 BBB对各种刺激的反应。长期目标是 一项提议是检验单核细胞迁移穿过血脑屏障的假设 可以通过各种因素来促进，例如，特异性细胞因子， 化学趋化因子和其他物质，影响活化状态， 单核细胞或脑微血管内皮细胞（BMEC）。初始 研究将评估单核细胞刺激/活化的作用， 脂多糖（LPS）、佛波醇肉豆蔻酸酯（PMA）和干扰素- γ（IFN-γ）。这些药物已被证明可以促进单核细胞 粘附/迁移穿过外周血管系统，但尚未 关于单核细胞与BBB的相互作用进行分析。这是 关键，因为BBB内皮细胞的行为可能与 外周血管后续研究将分析 LPS和细胞因子对内皮细胞的刺激/活化肿瘤坏死 因子-α（TNF-α）、IFN-γ和白细胞介素-1和-2（IL-1、IL-2） - 物质再次已知促进单核细胞迁移穿过 外周循环，并且，在细胞因子的情况下， 显示在脑中与单核细胞同时上调 浸润单核细胞/BMEC刺激的组合也将被考虑。 以观察这是否进一步增强单核细胞迁移。效果 还将评估BMEC感染巨细胞病毒（CMV）的风险， CMV感染艾滋病患者的BMEC，并已显示可增加单核细胞粘附 感染的外周血管内皮细胞。因此，巨细胞病毒可能有助于 向大脑募集单核细胞。单核细胞趋化因子的作用 肽MCP-1和TGF-β将另外进行分析，因为这些肽可能 在CNS炎症性疾病期间由星形胶质细胞释放， 促进单核细胞向大脑运输。这些研究将在 在存在和不存在星形胶质细胞条件培养基的情况下， 已被证明影响血脑屏障通透性，因此，神经胶质细胞， 衍生因子可能影响单核细胞迁移。BBB完整性将是 在这些研究过程中，电子和 荧光显微镜，以确定单核细胞迁移是否需要 或诱导内皮细胞损伤。抗体“阻断”实验将 也可用于鉴定细胞粘附分子：配体途径 在单核细胞穿过BBB的迁移中起作用。最后，影响 单核细胞：星形胶质细胞在单核细胞跨血脑屏障迁移中的相互作用 模型也将得到评估。这些实验将阐明 调节单核细胞进入大脑， 在各种中枢神经系统瘫痪中进行治疗干预的靶点 疾病