Role of Myeloid Cells in HIV latency in the Periphery and the CNS

 描述：从艾滋病流行的最初几天起，单核细胞和巨噬细胞已被证明是建立和维持艾滋病毒感染的关键角色(1)。单核/巨噬细胞在感染过程的各个方面的重要性已被广泛记载(2)。最值得注意的是，它们在建立和维持中枢神经系统(CNS)感染方面的作用已得到充分认识(3)。在过去的几年里，我们的实验室在开发和实施用于艾滋病毒研究的人源化小鼠方面取得了重大进展。特别是，我们为使用骨髓/肝脏/胸腺(BLT)人源化小鼠和纯T细胞小鼠(TOM)分析潜伏期和根除建立了关键参数。具体地说，我们已经建立了有效的抗逆转录病毒疗法(ART)，导致病毒抑制，建立了潜伏感染HIV的T细胞的发展，系统地量化了潜伏感染细胞在每个组织中的频率，并证明了潜伏感染可以在诱导后被体外干扰，从而导致病毒的产生。最后，我们实施了新的方法来杀死感染艾滋病毒的T细胞，这些细胞构成了残留的活性储存库，尽管抗逆转录病毒治疗仍在体内持续存在。通过平行的研究，我们最近实现了一种新的动物模型，它不同于所有其他现有的用于研究HIV的人源化小鼠模型，一个重要的事实是：它不包含任何人类T细胞。相反，除了人类B细胞外，它还含有完整的髓系细胞，包括单核细胞、巨噬细胞和树突状细胞，所有这些都是HIV感染、发病机制、传播、持久性和疾病进展的重要靶点。只有存在于包括大脑在内的所有组织中的人类髓系细胞才是HIV感染的目标的模型的可用性(命名为MOM，仅针对髓系小鼠)允许首次在体内详细研究髓系细胞在艾滋病毒感染、传播、发病机制、潜伏期和持久性中的作用。作为这笔赠款的一部分，我们建议实现以下具体目标：1)确定人源化MOM对巨噬细胞和T细胞嗜性病毒感染HIV-1的易感性。假设：在没有人类T细胞的情况下，巨噬细胞足以维持HIV在体内的复制。MOM可以作为一种高度创新的模型，在体内详细研究HIV感染髓系细胞的生物学和发病机制。2)检测ART对人源化母亲体内HIV-1复制的影响。为了更好地了解髓系细胞在艾滋病毒持久性中的作用，需要建立强有力的药理干预措施，能够有效地抑制艾滋病毒在这一间隔中的复制。假设：高效三联抗逆转录病毒疗法能有效抑制体内巨噬细胞中的HIV复制。3)探讨巨噬细胞在人源化母体外周和脑内HIV潜伏储存库的建立和维持中的作用。假设：巨噬细胞是HIV的储存库，有助于HIV在体内的持续存在。

 DESCRIPTION: From the earliest days of the AIDS epidemic, monocytes and macrophages have been shown to be key players in the establishment and maintenance of HIV infection (1). The importance of monocyte/macrophages in all aspects of the infectious process has been extensively documented (2). Most notably, their role in the establishment and maintenance of infection in the central nervous system (CNS) has been fully appreciated (3). Over the last several years, our laboratory has made significant progress towards the development and implementation of humanized mice for HIV research. In particular, we have established critical parameters for the use of bone marrow/liver/thymus (BLT) humanized mice and T cell only mice (ToM) for the analysis of latency and eradication. Specifically, we have established effective antiretroviral therapy (ART) that results in viral suppression, established the development of latently HIV infected T cells, quantitated the frequency of latently infected cells systemically an per tissue, and demonstrated that latency can be disrupted ex-vivo after induction resulting in virus production. Finally, we implemented novel approaches to kill HIV infected T cells that compose the residual active reservoir that persist in vivo despite ART. Through a parallel line of investigation, we have recently implemented a novel animal model that differs from all other existing humanized mouse models used to study HIV in one important fact: it does not contain any human T cells. Instead, in addition to human B cells, it contains a complete complement of myeloid cells including monocytes, macrophages and dendritic cells all of which are important targets for HIV infection, pathogenesis, transmission, persistence and disease progression. The availability of a model in which only the human myeloid-cells present in all tissues including the brain are targets of HIV infection (designated MoM, for myeloid only mice) permits, for the first time, detailed in vivo study of the role of myeloid cells in HIV infection, dissemination, pathogenesis, latency and persistence. As part of this grant we propose to carry out the following Specific Aims: 1) To establish the susceptibility of humanized MoM to HIV-1 infection by macrophage- and T cell-tropic viruses. Hypothesis: Macrophages are sufficient to sustain HIV replication in vivo in the absence of human T cells. MoM can serve as a highly innovative model in which to study in detail the biology and pathogenesis of HIV infection in myeloid cells in vivo. 2) To determine the effect of ART on HIV-1 replication in humanized MoM. A better understanding of the role of myeloid cells in HIV persistence requires the establishment of robust pharmacological interventions capable of efficiently suppressing HIV replication in this compartment. Hypothesis: Highly active triple combination antiretroviral therapy is effective at suppressing HIV replication in macrophages in vivo. 3) To characterize the role of macrophages on the establishment and maintenance of the latent HIV reservoir in the periphery and in the brain of humanized MoM. Hypothesis: Macrophages represent a reservoir of HIV that contributes to HIV persistence in vivo.