Role of gp120 in Neuropathogenesis in a New Model of HIV Infection in Mice

gp120 在小鼠 HIV 感染新模型神经发病机制中的作用

• 批准号: 7065917
• 负责人: DAVID J VOLSKY
• 金额: $ 18.16万
• 依托单位: ST. LUKE'S-ROOSEVELT INST FOR HLTH SCIS
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-01 至 2008-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7065917
• 关键词: HIV infections; astrocytes; brain; infection; macrophage; model; receptor; role; tissue mosaicism

DESCRIPTION (provided by applicant): We have recently established a novel model for HIV-1 infection in healthy immunocompetent mice. Mice inoculated i.v. or i.p. with EcoHIV, a chimeric HIV-1 carrying MLV envelope that mediates HIV-1 entry into mouse cells, become persistently infected, with production of antibodies to viral proteins and presence of virus in the spleen, peritoneal macrophages, and PBL. A large proportion of inoculated animals show evidence of early virus infiltration into the brain and elevated expression of genes such as MCP-1, STAT1, and IL-1b, which are associated with inflammation in brain tissue in humans. In contrast, relatively few animals displayed brain lesions indicative of overt brain disease. Thus EcoHIV is neurotropic and neuropathogenic in mice but it does not express HIV-1 gp120 and it appears to cause attenuated, "preclinical" brain disease in mice. HIV-1 gp120 is thought to contribute to neuropathogenesis through interaction with surface receptors on macrophages, astrocytes, and neurons. Preliminary studies indicate that HIV-1 carrying native gp120 induces a wider range of inflammatory molecules in mouse astrocytes in culture than EcoHIV. We hypothesize that expression of selected gp120 segments, such as V3, by EcoHIV will facilitate HIV-1-mediated neuropathogenesis in mice. The exploratory studies proposed here will evaluate this hypothesis in two Aims. In Aim 1, we will construct a series of chimeric EcoHIV with increasingly large HIV-1 gp120 regions around V3, including those responsible for interaction with surface receptors, inserted into MLV Env of EcoHIV. The chimeras will be tested for infectivity in vitro and in vivo and for their ability to induce inflammatory proteins in mouse macrophages and astrocytes in culture compared to EcoHIV. The first such chimera we constructed, EcoHIV-V3, was found to be infectious in vivo. In Aim 2, we will compare selected gp120- expressing chimeras and EcoHIV for induction of neuropathogenesis in mice. We will determine the kinetics of virus infection and neuroinvasion in vivo, the expression of selected molecular markers of HIV-1 neuropathogenesis in the brain, and the development of neuropathology. The proposed studies may help to define the role of HIV-1 gp120 in HIV-1-mediated neuropathogenesis in mice in distinction from contribution of the viral genome lacking gp120. The studies employ an animal model, molecular, and pathological analyses of animal tissues, and molecular virology and recombinant DMA technologies. In the larger public health context, our studies will establish the utility of this animal model of HIV-1 infection in research on HIV-1 pathogenesis, including that in the central nervous system, development of HIV-1 vaccine, and convenient inexpensive testing of antiviral compounds in vivo.

描述（由申请人提供）：我们最近在健康免疫活性小鼠中建立了一种新的HIV-1感染模型。经i. v.或i. p.接种EcoHIV（一种携带MLV包膜的嵌合HIV-1，介导HIV-1进入小鼠细胞）的小鼠持续感染，产生病毒蛋白抗体，脾脏、腹腔巨噬细胞和PBL中存在病毒。大部分接种的动物显示早期病毒浸润到大脑中的证据，以及MCP-1，STAT 1和IL-1b等基因的表达升高，这些基因与人类脑组织中的炎症有关。相比之下，相对较少的动物显示出明显的脑部疾病的脑部病变。因此，EcoHIV在小鼠中是嗜神经性和神经致病性的，但它不表达HIV-1 gp 120，并且似乎在小鼠中引起减弱的“临床前”脑疾病。HIV-1 gp 120被认为通过与巨噬细胞、星形胶质细胞和神经元上的表面受体相互作用而促进神经发病。初步研究表明，携带天然gp 120的HIV-1比EcoHIV在培养的小鼠星形胶质细胞中诱导更广泛的炎症分子。我们假设，选择的gp 120片段，如V3，EcoHIV的表达将促进HIV-1介导的小鼠神经发病机制。本文提出的探索性研究将从两个方面评估这一假设。在目标1中，我们将构建一系列嵌合EcoHIV，其中V3周围的HIV-1 gp 120区域越来越大，包括那些负责与表面受体相互作用的区域，插入EcoHIV的MLV Env中。将测试嵌合体的体外和体内感染性，以及与EcoHIV相比，其在培养物中诱导小鼠巨噬细胞和星形胶质细胞中的炎性蛋白的能力。我们构建的第一个这样的嵌合体EcoHIV-V3被发现在体内具有感染性。在目标2中，我们将比较选择的gp 120表达嵌合体和EcoHIV诱导小鼠神经发病机制。我们将确定体内病毒感染和神经侵袭的动力学，HIV-1神经发病机制的选定分子标记物在大脑中的表达，以及神经病理学的发展。拟议的研究可能有助于确定HIV-1 gp 120在HIV-1介导的小鼠神经发病机制中的作用，以区别于缺乏gp 120的病毒基因组的贡献。这些研究采用动物模型、动物组织的分子和病理学分析以及分子病毒学和重组DNA技术。在更大的公共卫生背景下，我们的研究将建立这种HIV-1感染的动物模型在HIV-1发病机制研究中的实用性，包括在中枢神经系统中，HIV-1疫苗的开发，以及方便廉价的体内抗病毒化合物测试。