HIV-1 Replication and Pathogenesis in vivo

ARRA第1-2年资助 该项目的目标是确定HIV-1如何与PDC相互作用，并阐明PDC的作用 细胞在HIV-1复制和发病机制中的作用。作为病毒感染的主要感受器，改变了PDC的水平/活性 可能在HIV-1疾病的发展过程中发挥关键作用。然而，PDC细胞在F-IIV感染和 发病机制尚不清楚，主要是由于缺乏可靠的体内模型。DKO-HU I-4SC型号是 非常适合这一目的。有了稳定的功能性人体免疫系统，功能性PDC细胞在 DKO-HU小鼠各淋巴器官比例正常。HIV-1建立持续感染，具有免疫力 人CD4T细胞的过度激活和耗竭。我们还表明，在HIV-1感染期间，PDC 在DKO-Hu HSC小鼠中，细胞被生产性地感染、激活、耗尽和功能受损。HIV-1与 致病的R3A Env在体外也能有效地激活PDC，这与其与CD4的高结合亲和力有关 受体和辅受体。根据我们的初步发现和来自Sly感染猴子或HIV的报告- 感染患者，假设HIV-1与PDC细胞密切相互作用，并慢性参与PDC 在持续的HIV感染期间，会耗尽或损害PDC的活性。PDC活性降低或改变 有助于慢性艾滋病毒感染、高免疫力激活和艾滋病的进展。 为了检验这些假说，我们提出了以下修改后的具体目标。首先，我们将调查 通过遗传分析候选信号通路(SA2a)，由HIV感染诱导。第三，我们将 慢性HIV-1早期和晚期POC细胞的增殖和存活 用遗传方法激活PDC。此外，我们还将定义PoC小区中的信号缺陷 第二，我们将明确角色 PDC活化过程中各相关受体(CD4、CCR5、CXCR4、BDCA2、TLR7和TLR9)的表达 特定的抑制剂和遗传方法。此外，我们还将从模拟-OR中纯化PDC细胞 以确定受艾滋病毒感染的DKO-HU小鼠的基因是否受艾滋病毒感染的影响。我们将定义 通过对候选信号的遗传学分析，研究HIV感染诱导的PDC细胞信号缺陷 小路。第三，我们将研究是否刺激或抑制PDC的激活与激动剂或 HIV感染前或感染期间TLR7/TLR9的拮抗配体将影响HIV的复制和 免疫发病机制。此外，我们还将用偶联的PDC特异性mAb治疗DKO-Hu小鼠 使用Saporin毒素，它专门消耗PDC，以测试PDC在感染过程中的作用。 因此，我们将集中讨论PDC细胞在HIV发病机制中最基本的问题。澄清： HIV-1与PDC细胞相互作用机制及其在HIV-1感染和艾滋病中的作用 发病机制不仅有助于我们理解pDC在HIV发病机制中的生物学作用，而且 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.