Elicitation of broad immunity using VLPs with consensus envs

使用具有共识环境的 VLP 引发广泛免疫

• 批准号: 7229376
• 负责人: Ted M Ross
• 金额: $ 70.36万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-28 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7229376
• 关键词: AIDS vaccine development; Address; Animals; Antibody Formation; Antigens; CCR5 gene; Cells; Cellular Immunity; Consensus; Cytomegalovirus; DNA; DNA Vaccines; Data; Early Promoters; Engineering; Evaluation; Evolution; Facility Construction Funding Category; Gagging; Genes; Geographic Locations; Glycoproteins; Goals; Guidelines; HIV-1; Human; Immune; Immune response; Immunity; Infection; Length; Libraries; Localized; Macaca mulatta; Messenger RNA; Modeling; Mutation; Nuclear Export; Population; Primates; Proteins; RNA Splicing; Role; Route; Safety; Structure; Subfamily lentivirinae; Surface; System; Translating; Treatment Protocols; United States Food and Drug Administration; Vaccinated; Vaccines; Vagina; Variant; Vertebral column; Viral; Viral Proteins; Virus; Virus-like particle; design; env Gene Products; nonhuman primate; novel virus; particle; plasmid DNA; pol genes; response; rev Genes; simian human immunodeficiency virus; transmission process

DESCRIPTION (provided by applicant): Among the greatest challenges facing AIDS vaccine development is the intrinsic diversity among circulating populations of HIV-1 in various geographical locations and the need to develop vaccines that can elicit enduring protective immunity to variant HIV-1 strains. While variation is observed in all of the viral proteins, the greatest diversity is localized to the viral envelope glycoproteins, evidently reflecting the predominant role of these proteins in eliciting host immune recognition and response that result in progressive evolution of the envelope proteins during persistent infection. In the current application, we have designed novel virus-like particle (VLP) immunogens that can optimize mucosal and systemic Env-specific immune responses for evaluation against protection from heterologous SHIV challenge in rhesus macaques by vaginal exposure (the most common route of HIV-1 transmission worldwide). We have constructed DNA plasmids to express VLPs from SHIV gene sequences where each DNA construct expresses a non-infectious lentiviral VLP from a single DNA plasmid. Each VLP gene insert expresses the gag, pol, env, vpu, tat, and rev gene sequences that are expressed from a cytomegalovirus immediate-early promoter via plasmid DNA. Thus, VLP mRNA splicing and nuclear export will be controlled by viral mechanisms and translated proteins efficiently secrete VLPs from transfected cells. Several safety mutations have been engineered into the backbone of the VLP to match the U.S. Food and Drug Administration guidelines for the use of HIV-1 DNA vaccines for human use. In this proposal, gene inserts expressing SHIV VLPs will be expressed from DNA. In addition, SHIV VLPs will be purified from the supernatant of primate cells transfected with the same DNA plasmids. We propose to construct and characterize a library of SHIV VLP-DNA plasmids, each containing a different CCR5 (RS)-utilizing clade B or clade C envelope glycoprotein of HIV-1. Rhesus macaques will be vaccinated in a prime/boost regimen (DNA prime/particle boost) for the elicitation of both humoral and cellular immunity, and protection from heterologous clade B SHIV challenge will be evaluated. The goals of this proposal are to assess and compare the induction of immune responses between VLP immunogens with primary envelopes to the elicitation of immunity by VLP immunogens with an envelope representing the consensus envelope sequences (clade B or clade C). SHIV-1 VLPs will also be assessed for elicitation of immunity and protection to a heterologous SHIV challenge. The use of a consensus envelope as a native oligomer allows for the comparison of protective immunity elicited by consensus envelopes to that elicited by a mixture of primary oligomeric envelopes that are mismatched to the challenge virus. Finally, the breadth and protective efficacy of immune responses elicted by a SHIV-1 VLP containing an envelope representing the consensus envelope sequence of clade C (Con C) will be evaluated with a clade B SHIV challenge.

描述（由申请人提供）：艾滋病疫苗开发面临的最大挑战之一是在各个地理位置的HIV-1循环种群中的内在多样性，并且需要开发疫苗，这些疫苗可以引起对变异HIV-1菌株的持久保护性免疫。尽管在所有病毒蛋白中都观察到变异，但最大的多样性位于病毒包膜糖蛋白上，显然反映了这些蛋白在引起宿主免疫识别和反应中的主要作用，从而导致持久感染过程中包膜蛋白的逐步演变。在当前的应用中，我们设计了新型病毒样颗粒（VLP）免疫原，可以优化粘膜和全身ENV特异性免疫反应，以评估阴道暴露（全球HIV-1传播的最常见途径）在恒河猴中的防御性SHIV挑战的保护。我们已经构造了DNA质粒来表达SHIV基因序列的VLP，其中每个DNA构建体从单个DNA质粒表达非感染的慢病毒VLP。每个VLP基因插入物都表示通过质粒DNA从巨细胞病毒立即启动子表达的GAG，POL，ENV，VPU，TAT和REV基因序列。因此，VLP mRNA剪接和核输出将由病毒机制控制，并翻译的蛋白质有效地从转染的细胞中分泌VLP。已经在VLP的骨架上设计了一些安全突变，以符合美国食品和药物管理局的使用指南，以供HIV-1 DNA疫苗用于人类使用。在此提案中，表达SHIV VLP的基因插入将从DNA表示。另外，SHIV VLP将从使用相同DNA质粒转染的灵长类动物细胞的上清液中纯化。我们建议构建和表征SHIV VLP-DNA质粒的库，每个库中含有不同的CCR5（RS），以利用HIV-1的CCR5（RS）来维修进化枝B或进化枝C包膜糖蛋白。恒河猕猴将在质量/增强方案（DNA Prime/颗粒增强剂）中接种疫苗，以促进体液和细胞免疫，并将评估避免异源进化枝B S SHIV挑战的保护。该提案的目标是评估和比较VLP免疫原子与主要信封之间的免疫反应的诱导，以通过VLP免疫原子具有代表共识包络序列的信封（进化枝B或进化枝C）对免疫的诱导。 SHIV-1 VLP还将被评估，以引起免疫力和保护异源SHIV挑战。将共识包膜用作天然低聚物的使用可以比较共识信封引起的保护性免疫与由原代低聚物信封的混合物引起的保护性免疫，这些寡素信封与挑战病毒不匹配。最后，通过包含代表进化枝C（con c）共识包络序列的信封的SHIV-1 VLP所产生的免疫反应的宽度和保护效果，并通过进化枝B SHIV挑战进行评估。