Overcoming Host Restriction Factors to Develop Better Animal Models for HIV/AIDS.

描述（由申请人提供）：HIV-1是人类艾滋病的主要原因，在大多数非人类物种中无法复制。因此，人类艾滋病最实用的动物模型是用SIVMAC或SIVMAC衍生的嵌合体感染恒河猴，这些嵌合体编码HIV-1包膜（SHIV）。然而，这些模型的实用性受到HIV-1和SIVMAC是不同病毒这一事实的限制。基于我们在过去几年中获得的对物种特异性限制因子的理解，我们已经产生了一种重组病毒，命名为向猴HIV (stHIV)，它几乎完全来源于HIV-1，但可以在体外的原代恒河猴和尾猴细胞中非常有效地复制。我们的初步数据表明，stHIV变异能够在恒河猴体内低水平复制，而在尾猴体内高水平复制。本提案的目的是产生具有增强复制能力和在动物中引起艾滋病的stHIV的改进衍生物，并利用这些病毒在体内研究HIV-1的发病机制。首先，我们将扩展我们最近的发现，即shiv变体可以在尾猴体内有效复制，并获得该病毒的分子克隆，该病毒在尾猴体内持续有效复制。基于这种病毒，我们将产生R5-tropic变体并启动粘膜传播研究。其次，我们将通过产生最小突变的HIV-1蛋白来减少shiv构建体中存在的SIVMAC序列，这些蛋白可以赋予对猕猴限制因子的抗性。第三，我们将确定SIVMAC蛋白在恒河猴体内stHIV复制中的作用。最后，我们将使用shiv模型来评估HIV-1辅助蛋白在病毒体内复制中的作用。最终，我们将产生与HIV-1毒株非常相似的HIV-1毒株，这种毒株在人类中传播，并在动物模型中引起艾滋病。如果成功，这些研究将彻底改变艾滋病治疗方法和疫苗的临床前探索和开发。

DESCRIPTION (provided by applicant): HIV-1, the predominant cause of AIDS in humans, is unable to replicate in most non-human species. Therefore, the most practical animal model of human AIDS consists of infection of rhesus macaques with SIVMAC or chimeras derived from SIVMAC that encode the HIV-1 envelope (SHIV). However, the usefulness of these models is limited by the fact that HIV-1 and SIVMAC are distinct viruses. Based on an understanding of species-specific restriction factors that we have acquired during the past few years, we have generated a recombinant viruses, named simian tropic HIV (stHIV), that are almost entirely derived from HIV-1 but can replicate very efficiently in primary rhesus and pigtailed macaque cells in vitro. Our preliminary data show that stHIV variants are able to replicate at low levels in rhesus and high levels in pigtailed macaques in vivo. The aims of this proposal are to generate improved derivatives of stHIV with enhanced ability to replicate and cause AIDS in animals and to use these viruses to study HIV-1 pathogenesis in vivo. First, we will expand our very recent findings that an stHIV variant can replicate efficiently in pigtailed macaques and derive a molecular clone of this virus that consistently replicates efficiently in pigtailed macaques in vivo. Based on this virus we will generate R5-tropic variants and initiate mucosal transmission studies. Second, we will reduce the SIVMAC sequences present in stHIV constructs by generating minimally mutated HIV-1 proteins that can confer resistance to macaque restriction factors. Third, we will determine the role of SIVMAC proteins in stHIV replication in rhesus macaques. Finally, we will use the stHIV model to assess the role of HIV-1 accessory proteins in virus replication in vivo. Ultimately, we will generate stHIVs that closely resemble HIV-1 strains that circulate in humans and cause AIDS in an animal model. If successful, these studies should revolutionize the preclinical exploration and development of AIDS therapeutics and vaccines. PUBLIC HEALTH RELEVANCE: HIV-1, the predominant cause of AIDS in humans, is unable to replicate in most nonhuman primate species and current animal models are limited. We have developed novel chimeric viruses based on HIV-1 and are proposing to test their utility as an HIV-1 infection model in monkeys and to generate additional HIV-1-derived viruses. If successful, this proposal will lead to improved animal models for HIV-1 infection and will considerably facilitate the development and testing of drug and vaccine interventions.