THE ROLE OF CYTOKINES IN THE PATHOGENESIS OF AIDS DEMENTIA COMPLEX

HIV-1感染通常伴有中枢神经损伤 系统。受影响的人往往表现出严重的、进行性的 行为和神经并发症。尽管精确的分子 以及与HIV脑病相关的细胞致病过程 仍不清楚，越来越多的证据表明对中枢神经系统的毒性是 间接地，部分地由宿主衍生的因素，如细胞因子， 为应对病毒感染而产生的。这项提案的重点是 假设一种关键的抗病毒细胞因子干扰素-α是系统性产生的 通过渗透免疫细胞或常驻脑细胞，有助于 HIV感染时的中枢神经系统损伤。为了检验这一假设，一个定义明确的 采用转基因的方法，将干扰素-α的表达 使用胶质纤维酸性蛋白-IFNalpha1靶向星形胶质细胞 融合基因构建。这种方法提供了一种独特而强大的 用于研究本质性神经致病后果的模型 完整中枢神经系统星形胶质细胞产生干扰素-α。初步 所谓G干扰素转基因小鼠的病理学特征 揭示了中枢神经系统广泛的结构和分子变化 从而直接支持了这样的观点，即干扰素-α很可能因此， 干扰素家族的其他成员可能在糖尿病的发生中起到了因果作用。 艾滋病毒脑病。在此，我们建议进一步扩大范围和 现有和新的神经病理评估的详细情况 将培育稳定的G干扰素小鼠品系。这项评估将采用 建立了一系列测试来检查中枢神经系统的分子和 细胞水平，包括核糖核酸酶保护试验、原位杂交、 Northern印迹杂交、蛋白质免疫印迹分析、常规光 免疫标记脑切片和电子显微镜的激光共聚焦显微镜 显微镜。将确定G干扰素小鼠中枢功能的改变 在行为、电生理和神经内分泌水平以及在哪里 可能与特定的分子和细胞变化有关。这个 将在#年评估不同致病因素对神经系统的影响 G干扰素小鼠的研究：I)GFAP-干扰素小鼠与小鼠的杂交 其他转基因背景(如GFAP-IL6或GFAP-gp120)，ii)内部 嗜神经性病毒的神经感染和回交繁殖 用SCID小鼠建立免疫剥夺的GFAP细胞因子转基因动物。 这些研究将概括多因素的性质 致病过程是HIV脑病的思想基础。最后， 特征良好的G干扰素小鼠将被用于鉴定和评估 体内药物的疗效针对有害的干扰素-中枢神经系统相互作用。这 研究提供了一种独特而有力的方法来阐明分子。 以及干扰素-α在体内中枢神经系统病理生物学的细胞学基础 促进治疗策略的开发和测试 减轻这种细胞因子对中枢神经系统的毒性作用。

HIV-1 infection is commonly accompanied by injury to the central nervous system. Affected individuals frequently exhibit serious, progressive behavioral and neurological complications. Although the precise molecular and cellular pathogenetic processes associated with HIV encephalopathy remain unknown, accumulating evidence suggest toxicity tot he CNS amy be mediated indirectly, in part, by host derived factors such as cytokines, produced in response to the viral infection. This proposal focuses on the hypothesis that a key antiviral cytokine IFN-alpha, produced systemically and by infiltrating immune cells or resident brain cells, contributes to CNS injury during HIV-infection. To test this hypothesis, a well defined transgenic approach was employed in which the expression of IFN-alpha was targeted to astrocytes using a glial fibrillary acidic protein-IFNalpha1 fusion gene construct. This approach has provided a unique and powerful model to study the neuropathogenic consequences of the constitutive production of IFN-alpha from astrocytes in the intact CNS. Preliminary pathological characterization of so-called GIFN transgenic mice has unveiled wide-ranging structural and molecular alterations of the CNS thereby directly supporting the view that IFN-alpha, and likely therefore, other members of the IFN family, may have a causal role in the genesis of HIV encephalopathy. Here, we propose to further expand the scope and detail of the neuropathological assessment in an existing as well as in new stable lines of GIFN mice to be developed. This assessment will employ an established battery of tests to examine CNS alterations the molecular and cellular levels., including RNase protection assay, in situ hybridization, northern blot hybridization, protein immunoblot assay, conventional light and laser confocal microscopy of immunolabeled brain sections and electron microscopy. Functional CNS alterations in the GIFN mice will be determined at the behavioral, electrophysiological and neuroendocrine levels and where possible be linked to specific molecular and cellular alterations. The neurological impact of different pathogenetic factors will be assessed in the GIFN mice by: i) cross-breeding of the GFAP-IFN mice with mice from other transgenic backgrounds (e.g. GFAP-IL6 or GFAP-gp120), ii) intra- neural infection with neurotropic viruses and, iii) back-cross breeding with SCID mice to develop immunodeprived GFAP-cytokine transgenic animals. These studies will recapitulate the multi-factorial nature of the pathogenetic process the thought to underlie HIV encephalopathy. Finally, the well characterized GIFN mice will be used to identify and assess in vivo the efficacy of drugs targeted at harmful IFN-CNS interactions. This study provides a unique and powerful approach to elucidate the molecular and cellular basis for the CNS pathobiology of IFN-alpha in vivo and will facilitate the development and testing of therapeutic strategies to alleviate the toxic CNS actions of this cytokine.