TRANSENDOTHELIAL MIGRATION OF ACTIVATED MONOCYTES IN HIV

HIV 中激活的单核细胞的跨内皮迁移

• 批准号: 2037758
• 负责人: HOLLY H BIRDSALL
• 金额: $ 18.75万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-12-15 至 1997-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2037758
• 关键词: B lymphocyte; HIV infections; T lymphocyte; astrocytes; cell adhesion; cell migration; cytomegalovirus; flow cytometry; human immunodeficiency virus 1; human tissue; immunocytochemistry; interleukin 1; laboratory rat; leukocyte activation /transformation; leukocyte adhesion molecules; monoclonal antibody; monocyte; nervous system infection; tissue /cell culture; vascular endothelium

Perivascular collections of macrophages and endogenous microglial cells appear to be major reservoirs of HIV- l within the central nervous system (CNS) and a source of viral and host cell products which have been implicated in the pathophysiology of dementia and other neurologic manifestations of HIV-l infection. Mechanisms responsible for the accumulation of these mononuclear leukocytes (MNL) in the CNS and, specifically, the contribution of peripheral blood leukocytes to these interstitial infiltrates have not been determined, nor is it clear whether the virus is carried to the CNS within infected PBL. Preliminary studies demonstrate that HIV- l infection stimulates cell surface expression of molecules on MNL which mediate adhesive interactions with endothelium and neural cells. Moreover we have found that peripheral blood monocytes from HIV- l infected subjects are frequently activated. They display increased quantities of these same adhesins and are more likely to adhere to cultured neural cells in vitro. The experiments proposed in this application will evaluate the ability of MNL from HIV-I infected subjects to migrate across endothelial cell monolayers. Using in vitro methods which allow us to harvest, enumerate and compare the phenotypes of leukocytes which have the capacity to adhere to, and migrate across endothelium, we propose to investigate whether HIV- l infected cells are particularly abundant in this population and evaluate whether infection with putatively "neurotropic" strains of HIV- l enhances their ability to migrate across endothelium. Factors which may modulate endothelial transmigration of MNL will also be investigated, including the effects of astrocytes growing in contiguity with endothelial monolayers, infection of endothelial cells with cytomegalovirus and stimulation with cytokines, such as IL- l, that are likely to be released by activated MNL or endothelial cells. Adhesive interactions between MNL, which have demonstrated their ability to migrate through endothelial barriers, and neural cells will be investigated in an attempt to identify the molecular basis for these interactions. Monoclonal antibodies (mAbs) specific for beta integrins, selectins and other molecules known to mediate heterotypic adhesive cellular interactions will be used in an attempt to block the binding of MNL to neural cells. We also plan to raise antibodies to ligands that resist the ability of presently available mAbs to block adhesive interactions in order to fully characterize the array of molecules used by HIV-l infected and/or activated MNL to attach to neural cells. Upon completion, we postulate that the proposed investigations will provide a better understanding of the mechanisms in HIV- l infected individuals which regulate trafficking of MNL across blood vessels and cause them to be retained within the CNS.

血管周围巨噬细胞和内源性小胶质细胞的聚集 似乎是中枢神经系统内 HIV-1 的主要储存库 （中枢神经系统）以及病毒和宿主细胞产品的来源 与痴呆和其他神经系统疾病的病理生理学有关 HIV-1感染的表现。负责的机制 这些单核白细胞（MNL）在中枢神经系统中的积累， 具体来说，外周血白细胞对这些的贡献 间质浸润尚未确定，也不清楚是否 病毒在受感染的 PBL 内被携带至中枢神经系统。初步研究 证明 HIV-1 感染刺激细胞表面表达 MNL 上介导与内皮细胞粘附相互作用的分子 神经细胞。此外，我们还发现外周血单核细胞 HIV-1感染者经常被激活。他们显示增加 这些相同的粘附素的数量并且更有可能粘附 体外培养神经细胞。本文提出的实验 应用程序将评估 HIV-I 感染受试者的 MNL 能力 迁移穿过内皮细胞单层。使用体外方法 这使我们能够收获、枚举和比较表型 具有粘附和迁移能力的白细胞 内皮细胞，我们建议研究 HIV-1 感染细胞是否 该人群中特别丰富，并评估是否感染 与假定的“嗜神经”HIV-l 菌株一起使用可增强其 迁移穿过内皮。可能调节内皮细胞的因素 MNL 的迁移也将受到调查，包括 星形胶质细胞与单层内皮细胞​​相邻生长，感染 内皮细胞与巨细胞病毒和细胞因子刺激， 例如 IL-1，可能由激活的 MNL 或 内皮细胞。 MNL 之间的粘合相互作用， 证明了它们穿过内皮屏障迁移的能力，并且 将研究神经细胞，试图识别分子 这些交互的基础。特异性单克隆抗体 (mAb) β整合素、选择素和其他已知介导异型的分子 粘附性细胞相互作用将被用来试图阻止 MNL 与神经细胞的结合。我们还计划提高抗体 抵抗目前可用单克隆抗体阻断能力的配体 粘附相互作用，以充分表征阵列 HIV-1感染和/或激活的MNL使用的分子附着于神经 细胞。完成后，我们假设拟议的调查将 提供对 HIV-1 感染机制的更好理解 监管 MNL 跨血管贩运的个人，以及 使它们保留在中枢神经系统内。