MODULATION OF CELL-MEDIATED IMMUNE FUNCTION BY OPIATES

因为它们损害细胞介导的免疫，阿片类药物被牵连 作为注射药物中HIV-1感染进展的辅助因子 使用（IDU）人群。 然而，关于这方面的数据很少。 阿片类药物对感染关键部位细胞防御的影响 艾滋病，例如，中枢神经系统（CNS）。 在本申请中， 实验提出了检验假设，阿片类调节 小胶质细胞和星形胶质细胞（大脑的免疫细胞）的功能， 从而促进HIV-1和弓形虫的发病， 是艾滋病患者中枢神经系统疾病的最重要原因。 因为 研究表明，内源性阿片肽和可卡因有许多共同点， 由于吗啡的免疫调节活性，这些药剂还 追究 将采取两种方法，一种涉及体外 小鼠脑细胞培养模型和其他涉及小鼠模型 弓形体脑炎的症状 体外研究的目的是 从初步研究表明吗啡改变了 小胶质细胞和星形胶质细胞产生两种关键的免疫细胞， 介质：细胞因子和自由基。 纯化新生鼠 小胶质细胞、纯化的星形胶质细胞或这些胶质细胞的共培养物 将用于表征：1） 吗啡、内源性阿片肽和可卡因对细胞因子释放的影响 和星形胶质细胞产生的自由基， 小胶质细胞，2）吗啡，内源性阿片肽， 可卡因对小胶质细胞和星形胶质细胞介导的神经元细胞损伤的影响，3） 吗啡和可卡因对胶质细胞诱导HIV-1表达上调的影响 1在慢性感染的前单核细胞中的表达及其作用 这些药物对HIV-1诱导的神经毒性的影响，以及4） 吗啡对小胶质细胞防御T.弓形虫及其影响 T上的吗啡gondii介导的神经毒性。 的具体目标 体内研究将描述慢性吗啡 中枢神经系统弓形虫病。 对于体外研究， 免疫调节活性的内源性阿片样物质，发现内 将通过使用阿片受体激动剂来研究大脑， 对δ和κ位点具有高度选择性的拮抗剂。 的 体外和体内研究的重点，以及相关方法， 将是那些细胞因子（肿瘤坏死因子-α，转化生长 因子-β，白细胞介素[IL]-1，IL-6）和自由基（超氧化物， 一氧化氮）参与HIV-1或T. 刚地。 这项研究是我们早期工作的逻辑延伸。 阿片类药物和可卡因对外周免疫细胞的影响 大脑的免疫细胞不仅是药物的主要靶器官， 也是HIV-1感染的原因。 这些研究包括在具体的 目标将有助于我们了解如何实现长期目标， 阿片类药物是艾滋病的辅助因子， 在注射吸毒人群中发展成全面艾滋病。

Because they impair cell-mediated immunity, opiates have been implicated as a cofactor in the progression of HIV-1 infection in the injection drug use (IDU) population. However, little data are available regarding the impact of opiates on cellular defenses at critical sites of infection in AIDS, e.g., the central nervous system (CNS). In this application, experiments are proposed for testing the hypothesis that opiates modulate the function of microglia and astrocytes (the brain's immune cells) and thus promote the pathogenesis of HIV-1 and Toxoplasma gondii, two of the most important causes of CNS disease in AIDS patients. Because of studies showing that endogenous opioid peptides and cocaine share many of the immunomodulatory activities of morphine, these agents will also be investigated. Two approaches will be taken, one involving in vitro murine brain cell culture models and the other involving murine models of toxoplasmic encephalitis. The aims of the in vitro studies have evolved from preliminary studies demonstrating that morphine alters the production by microglia and astrocytes of two key classes of immune mediators: cytokines and free radicals. Purified neonatal murine microglial cells, purified astrocytes, or cocultures of these glial cells with neuronal cells will be used to characterize: 1) the effects of morphine, endogenous opioid peptides, and cocaine on cytokine release from microglia and astrocytes and on the generation of free radicals by microglia, 2) the influence of morphine, endogenous opioid peptides, and cocaine on microglia- and astrocyte-mediated neuronal cell injury, 3) the impact of morphine and cocaine on glial cell-induced upregulation of HIV- 1 expression in chronically infected promonocytic cells and the effect of these drugs on HIV-1-induced neurotoxicity, and 4) the effect of morphine on microglial cell defense against T. gondii and the influence of morphine on T. gondii-mediated neurotoxicity. The specific aim of the in vivo studies will be to characterize the effect of chronic morphine administration on CNS toxoplasmosis. For the in vitro studies, the immunomodulatory activities of endogenous opioids that are found within the brain will be studied by using opioid receptor agonists and antagonists that are highly selective for delta and kappa sites. The focus of the in vitro and in vivo studies, and the related methodologies, will be those cytokines (tumor necrosis factor-alpha, transforming growth factor-beta, interleukin[IL]-1, IL-6) and free radicals (superoxide, nitric oxide) implicated in the neuroimmunopathogenesis of HIV-1 or T. gondii. This research is a logical extension of our earlier work ont he effects of opiates and cocaine on peripheral immune cells to studies of immune cells of the brain, a principal target organ not only for drugs of abuse but also for HIV-1. The studies encompassed in the specific aims will contribute to our long-term objectives of understanding how opiates act as a cofactor in AIDS and of devising ways to interfere with the development of full-blown AIDS in the IDU population.