Exploring antibody-Fc effector function in humanized mouse models of HIV latency

探索 HIV 潜伏期人源化小鼠模型中的抗体 Fc 效应子功能

• 批准号: 9050087
• 负责人: Priti Kumar
• 金额: $ 22.09万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-12-01 至 2017-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9050087
• 关键词: Animal Model; Anti-Retroviral Agents; Antibodies; Binding; Biological Assay; CCR5 gene; CD4 Positive T Lymphocytes; Capsid; Carrying Capacities; Cell Count; Cells; Code; Collaborations; Complement; Coupled; DNA; Dinitrophenols; Disease; Disease remission; Dose; Elements; Epitopes; Frequencies; Generations; Genomic DNA; Glycoproteins; Grant; HIV; HIV Infections; Human; Immune; Individual; Injection of therapeutic agent; Intramuscular; Investigation; Knowledge; Leukocytes; Life; Light; Measurement; Medicine; Modeling; Monitor; Mouse Strains; Mus; Muscle; Natural Killer Cells; Patients; Peripheral; Persons; Pharmaceutical Preparations; Phase; Plasma; Population; Prevention; Production; Proviruses; Recombinants; Recruitment Activity; Role; Serotyping; Skeletal Muscle; Surface; System; T memory cell; Testing; Tetanus Helper Peptide; Tetracyclines; Therapeutic; Therapeutic Effect; Time; Treatment Efficacy; Viral; Viral Load result; Viral reservoir; Viremia; antiretroviral therapy; base; college; complement system; expectation; gp160; gutless adenoviral vector; humanized mouse; interest; man; mouse model; neutralizing antibody; nonhuman primate; novel; novel strategies; peptidomimetics; peripheral blood; prevent; promoter; prophylactic; public health relevance; simian human immunodeficiency virus; small molecule; success; transgene expression

 DESCRIPTION (provided by applicant): There is currently considerable emphasis on strategies for eradicating HIV from infected individuals. Although much effort is focused on reactivating integrated provirus using small molecules, a second possibility is using broadly neutralizing antibodies (bNAbs) that are highly potent and active against diverse strains and clades of HIV. Recent evidence demonstrating the ability of bNAbs in delaying viral rebound after stopping antiretroviral treatment (ART) indicate that these antibodies may be able to clear or remove cells expressing envelope glycoprotein on their surface, effectively reducing the pool size of persistently-infected cells. We propose to investigate a role for bNAbs in actively eliminating or reducing the size of the persistent viral reservoir, in novel humanized models of ART-suppressed HIV infection that support antibody-effector function. In the first of three specific aims, we will construct `gutted' or helper-dependent adenoviral (HDAd) vectors, encoding the heavy and light chains of three second-generation bNAbs, in view of the downstream intramuscular application in animal models described in Aims 2 and 3. In the second aim, these vectored bNABs will be tested in HIV-infected humanized BLT mice, in which viral loads will be suppressed to undetectable levels by ART, for measurements of the latent viral pool size by genomic DNA qPCR and viral outgrowth assays. In particular, novel humanized mouse models that have active complement and functional natural killer cells will be used to assess the role of bNAb effector function in shrinking the persistently infected reservoir. In the final aim, the vectored bNAbs will be tested for their ability to shrink viral reservoirs in humanized mice derived using peripheral blood leukocytes from ART-suppressed HIV+ patients with undetectable plasma viral loads. On the basis of the investigations to be conducted in the R21 phase of this application, we anticipate establishing a critical role for bNAb-effector activit targeting persistent viral reservoirs. The R33 phase of the application will extend these studies to the testing of tetracycline-regulable bnAbs encoded in HDAds, possible due to large carrying capacity of HdAds (~30 kb). In addition to exploring newer, more potent bNAbs, we will also test the use of the recently described eCD4-Ig, that encodes both soluble CD4-Ig and a CCR5 peptidomimetic and ARM-Hs, which are bivalent small molecules capable of binding the CD4 binding pocket of gp160 and also recruiting anti-dinitrophenol antibodies for effector activity. This approach of using HDAds encoding bNAbs may also be combined with latency reversal agents, in order to clear out infected cells. The results of these investigations should accelerate the use of bNAbs as an adjunct to ART in the treatment of HIV disease, with the potential for functional eradication due to elimination or prevention of reactivation of persistently-infected cells.

 描述(由申请人提供)：目前相当重视从感染者身上根除艾滋病毒的战略。虽然很多工作都集中在使用小分子重新激活整合的前病毒上，但第二种可能性是使用广泛的中和抗体(BNAbs)，这种抗体对不同的HIV毒株和分支具有高度的效力和活性。最近的证据表明，bNAbs在停止抗逆转录病毒治疗(ART)后能够延缓病毒反弹，表明这些抗体可能能够清除或清除表面表达包膜糖蛋白的细胞，有效地缩小持续感染细胞的池大小。我们建议在支持抗体效应器功能的ART抑制的HIV感染的新型人源化模型中，研究bNAbs在主动消除或减少持久病毒库大小方面的作用。在三个特定目标中的第一个目标中，我们将构建编码三个第二代bNAbs重链和轻链的‘内切’或辅助依赖腺病毒(HDAd)载体，鉴于在AIMS 2和3中描述的动物模型的下游肌肉内应用。在第二个目标中，这些载体bNAbs将在HIV感染的人源化BLT小鼠中进行测试，其中病毒载量将被ART抑制到无法检测的水平，用于通过基因组DNA定量聚合酶链式反应和病毒生长分析来测量潜在的病毒池大小。特别是，具有活跃补体和功能性自然杀伤细胞的新型人源化小鼠模型将被用来评估bNAb效应器功能在缩小持续感染的宿主中的作用。 在最终目标中，将测试矢量化的bNAbs缩小病毒存储空间的能力。 人源化小鼠，来自无法检测到血浆病毒载量的ART抑制的HIV+患者的外周血白细胞。在这项应用的R21阶段将进行的研究的基础上，我们预计将建立针对持久病毒库的bNAb效应激活蛋白的关键作用。R33阶段的应用将把这些研究扩展到HDAD编码的四环素可调节bNAbs的测试，这可能是因为HdAds的载量很大(~30kb)。除了探索更新、更有效的bNAbs外，我们还将测试最近描述的eCD4-Ig的使用，它既编码可溶的CD4-Ig，也编码CCR5模拟肽和ARM-HS，这是能够结合gp160的CD4结合口袋的二价小分子，也可以招募抗二硝基酚抗体来发挥效应。这种使用HDAd编码bNAbs的方法也可以与潜伏期反转剂相结合，以清除受感染的细胞。这些调查的结果应该加快。 在艾滋病毒疾病治疗中使用bNAbs作为抗逆转录病毒疗法的辅助手段，由于消除或防止持续感染的细胞重新激活，有可能实现功能性根除。