Determinants of retroviral replication in non-native hosts for modeling HIV infection

用于模拟 HIV 感染的非本地宿主逆转录病毒复制的决定因素

• 批准号: 10655753
• 负责人: Amit Sharma
• 金额: $ 67.97万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-17 至 2023-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10655753
• 关键词: Affect; Binding; Binding Sites; Biological; Biological Models; CD4 Positive T Lymphocytes; Cells; Data; Development; Genes; Glycoproteins; Goals; HIV Infections; HIV-1; Human; Immune; In Vitro; Infection; Integral Membrane Protein; Integration Host Factors; Interferon Type I; Interferons; Laboratories; Link; Lymphocyte; Macaca; Maps; Modeling; Molecular; Molecular Conformation; Mucous Membrane; Mutation; Pathogenicity; Polysaccharides; Prevention; Primary Infection; Process; Production; Proteins; Research Proposals; Resistance; Role; SIV; Serial Passage; Structure; T-Lymphocyte Subsets; Time; Vaccines; Variant; Viral; Virion; Virus; Virus Diseases; Virus Replication; base; chronic infection; efficacious intervention; improved; in vivo; insight; macrophage; memory CD4 T lymphocyte; monocyte; neutralizing antibody; non-Native; prevent; rational design; response; simian human immunodeficiency virus; transmission process; virus tropism

PROJECT SUMMARY/ABSTRACT HIV-1 does not persistently infect macaques due to restriction by several species-specific host factors necessitating the use of chimeric SIV/HIV-1 viruses (SHIVs) as surrogates to model HIV-1 infection in macaques. Infection of macaques with SHIVs is the most preferred model system for vaccine and prevention studies because SHIVs encode HIV-1 Envelope glycoprotein (Env) – a key target of HIV-1 neutralizing antibodies. Because the goal of vaccines is to prevent new infection, SHIVs based on circulating, transmitted forms of Env variants are desired as challenge viruses. Existing SHIV/macaque models typically employ SHIVs that encode HIV-1 Env from laboratory-adapted viruses, whose neutralization sensitivities differ from circulating Env variants. This significantly limits the ability of the existing SHIV/macaque models to predict efficacious intervention(s) in humans. Development of SHIVs encoding circulating Env variants has been extremely challenging, mainly because such SHIVs replicate poorly in macaques, if at all. To increase their replication and pathogenicity, SHIVs require extensive adaptation in vivo via serial passage in macaques. The process of serial macaque passage results in accumulation of adaptive mutations in Env that facilitates robust replication. Serial passage is typically performed within the first two weeks of infection, a time during which macaques mount a robust type-I interferon (IFN) response to infection. The host IFN response presents an early barrier against infection because production of IFNs upregulates expression of several IFN-stimulated genes (ISGs), which results in induction of an ‘antiviral state’. Proteins encoded by certain ISGs, referred to as restriction factors, act as potent barriers against cross-species lentiviral transmission. Thus, macaque restriction factors have the potential to block SHIV infection as they can antagonize HIV-1 Env. We recently identified macaque interferon-induced transmembrane proteins (IFITMs) as ISGs that selectively restrict replication of SHIVs encoding circulating HIV-1 Env variants. Our preliminary results suggest that unpassaged SHIV is potently inhibited by IFN in macaque lymphocytes. In contrast, serial passaged SHIVs are resistant to IFN. We found that the loss to two N-linked glycans in Env upon serial passage is sufficient to increase replication and confer resistance to IFN. This research proposal will: 1) characterize the adaptive changes in Env of serial passaged SHIVs that increase replication and IFN resistance; 2) determine the role of N-linked Env glycans in SHIV infection of primary macaque immune cell subsets ex vivo, and mucosal transmission and pathogenicity of SHIVs in vivo; and 3) evaluate the contribution of five macaque IFITM homologs, which are upregulated by IFN, in restriction of unpassaged, IFN-sensitive SHIV. Upon completion, this study will provide mechanistic insights at the host-viral interface that drive selection, adaptation, and pathogenicity of SHIVs in macaques.

项目概要/摘要 由于受到几种物种特异性宿主因素的限制，HIV-1 不会持续感染猕猴 需要使用嵌合 SIV/HIV-1 病毒 (SHIV) 作为替代物来模拟猕猴中的 HIV-1 感染。 猕猴感染 SHIV 是疫苗和预防研究的首选模型系统 因为 SHIV 编码 HIV-1 包膜糖蛋白 (Env)，这是 HIV-1 中和抗体的关键靶点。 由于疫苗的目标是预防新的感染，因此基于循环、传播形式的 Env 的 SHIV 需要变种作为挑战病毒。现有的 SHIV/猕猴模型通常使用编码 SHIV 来自实验室适应病毒的 HIV-1 Env，其中和敏感性与循环的 Env 变体不同。 这极大地限制了现有 SHIV/猕猴模型预测有效干预措施的能力 人类。编码循环环境变体的 SHIV 的开发极具挑战性，主要是 因为此类 SHIV 在猕猴体内的复制能力很差（如果有的话）。为了增加其复制和致病性，SHIV 需要通过猕猴的连续传代在体内进行广泛的适应。猕猴连续传代的过程 导致 Env 中适应性突变的积累，从而促进稳健的复制。 连续传代通常在感染后的前两周内进行，在此期间猕猴 对感染产生强大的 I 型干扰素 (IFN) 反应。宿主干扰素反应是一个早期障碍 抗感染，因为干扰素的产生会上调一些干扰素刺激基因（ISG）的表达， 这导致诱导“抗病毒状态”。由某些 ISG 编码的蛋白质，称为限制性蛋白质 因素，作为跨物种慢病毒传播的有效屏障。因此，猕猴的限制因素 具有阻止 SHIV 感染的潜力，因为它们可以拮抗 HIV-1 Env。我们最近发现了猕猴 干扰素诱导跨膜蛋白 (IFITM) 作为选择性限制 SHIV 复制的 ISG 编码循环的 HIV-1 Env 变体。 我们的初步结果表明，猕猴淋巴细胞中的 IFN 能有效抑制未传代的 SHIV。 相反，连续传代的 SHIV 对 IFN 具有抗性。我们发现 Env 中两个 N 连接聚糖的丢失 连续传代后足以增加复制并赋予对 IFN 的抗性。该研究计划将： 1) 表征连续传代的 SHIV 的 Env 的适应性变化，这些变化增加了复制和 IFN 反抗; 2)确定N联Env聚糖在SHIV感染原代猕猴免疫细胞中的作用 SHIV 的离体亚群以及体内粘膜传播和致病性； 3）评估贡献 五种猕猴 IFITM 同源物，受 IFN 上调，限制未传代的 IFN 敏感 艾滋病毒。完成后，这项研究将提供宿主-病毒界面的机制见解，从而驱动选择， SHIV 在猕猴中的适应和致病性。