HIV-1 Replication and Pathogenesis in vivo

为ARRA第1- 2年提供资金 本项目的目标是确定HIV-1如何与pDC相互作用，并阐明pDC的作用 HIV-1复制和发病机制中的细胞。作为病毒感染的主要感受器，改变的pDC水平/活性 可能在HIV-1疾病进展过程中起关键作用。然而，pDC细胞在F-IIV感染中的作用和 其发病机制知之甚少，主要是由于缺乏稳健的体内模型。DKO-hu I-4SC型号是 非常适合这个目的。在稳定的功能性人免疫系统的情况下，功能性pDC细胞在哺乳动物中发育。 DKO-hu小鼠所有淋巴器官中的正常比例。HIV-1建立持续感染，免疫 人CD 4 T细胞的过度活化和耗竭。我们还表明，在HIV-1感染期间，PDC 细胞在DKO-hu HSC小鼠中被生产性感染、活化、耗尽和功能受损。HIV-1， 致病性R3 A Env还在体外有效地激活PDC，这与其对CD 4的高结合亲和力有关 受体和辅助受体。根据我们的初步发现和报告，从狡猾的感染猴子或艾滋病毒- 感染的患者，假设HIV-1与PDC细胞密切相互作用，并且PDC的慢性接合 在持续的HIV感染期间，会消耗或损害PDC活性。PDC活性降低或改变 导致慢性HIV感染、超免疫激活和艾滋病进展。 提出了以下修改的具体目标来检验这些假设。首先，我们将调查 通过对候选信号通路（SA 2a）进行遗传分析，发现其由HIV感染诱导。三是 pOC细胞在早期和晚期慢性HIV-1中的增殖和存活 用遗传方法活化pDC。此外，我们还将定义pOC细胞中的信号缺陷 第二，我们要明确角色 pDC活化中的每种相关受体（CD 4、CCR 5、CXCR 4、BDCA 2、TLR 7和TLR 9）， 特异性抑制剂和遗传方法。此外，我们还将从模拟或培养的pDC细胞中纯化pDC细胞。 HIV感染的DKO-hu小鼠，以鉴定HIV感染后失调的基因。我们将定义 HIV感染诱导的pDC细胞中的信号传导缺陷，通过遗传分析候选信号传导， 途径。第三，我们将研究用激动剂或抑制剂刺激或抑制pDC活化是否有效。 在HIV感染之前或期间，TLR 7/TLR 9的拮抗配体将影响HIV复制， 免疫发病机制此外，我们将用缀合的pDC特异性mAb治疗DKO-hu小鼠， 用皂草素毒素，其特异性地消耗pDC，以测试pDC在感染期间的作用。 因此，我们将重点关注pDC细胞在HIV发病机制中的最基本问题。阐明 HIV-1与pDC细胞相互作用的机制及其在HIV-1感染和AIDS中的作用 发病机制不仅有助于我们理解HIV发病机制中的pDC生物学， 开发新的治疗策略。

forARRA years 1-2funding The goals of this project are to define how HIV-1 interacts with pDC and to elucidate the role of pDC cells in HIV-1 replication and pathogenesis. As the major sensor of viral infections, altered pDC level/activity may playa critical role during HIV-1 disease progression. However, the role of pDC cells in F-IIV infection and pathogenesis is poorly understood, mainly due to the lack of robust in vivo models. The DKO-hu I-4SC model is ideal for this purpose. With a stable functional human immune system, functional pDC cells are developed in normal proportion in all lymphoid organs in DKO-hu mice. HIV-1 establishes persistent infection, with immune hyperactivation and depletion of human CD4 T cells. We have also shown that, during HIV-1 infection, PDC cells are productively infected, activated, depleted and functionally impaired in DKO-hu HSC mice. HIV-1 with the pathogenic R3A Env also efficiently activates PDC in vitro, correlated with its high binding affinity to CD4 receptor and coreceptors. Based on our preliminary findings and reports from Sly-infected monkeys or HIV- infected patients, postulate that HIV-1 intimately interacts with PDC cells, and chronic engaging of PDC during persistent HIV infection wifl deplete or impair PDC activity. The reduced or altered PDC activity contributes to chronic HIV infection, hyperimmune activation and AIDS progression. The following modified specific aims are proposed to test these hypotheses. First, we wil iinvestigate the Induced by HIV infection, by genetically analyzing the candidate signaling pathways (SA2a). Third, we will proliferation and survival of pOC cells during early and late-chronic HIV-1 pDC activation with genetic approaches. In addition, we will also define the signaling defects in pOC cells Second, we will define the role of each relevant receptor (CD4, CCR5, CXCR4, BDCA2, TLR7 and TLR9) in pDC activation with specific inhibitors and with genetic approaches. In addition, we will also purify pDC cells from mock- or HIV-infected DKO-hu mice to identify genes that are deregulated by HIV infection. We will define the signaling defects in pDC cells induced by HIV infection, by genetically analyzing the candidate signaling pathways. Third, we will study if stimulation or inhibition of pDC activation with the agonistic or antagonistic ligands of TLR7/TLR9 before or during HIV infection will affect HIV replication and immuno-pathogenesis. In addition, we will treat DKO-hu mice with the pDC-specific mAb conjugated with the Saporin toxin, which specifically depletes pDC, to test the role of pDC during infection. We will thus focus on the most fundamental questions of pDC cells in HIV pathogenesis. Elucidation of the mechanism by which HIV-1 interacts with pDC cells and their role in HIV-1 infection and AIDS pathogenesis will facilitate not only our understanding of pDC biology in HIV pathogenesis, but also development of novel therapeutic strategies.