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: 7500255
• 负责人: Ted M Ross
• 金额: $ 66.72万
• 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/7500255
• 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; 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不同地理位置的HIV-1循环人群之间的内在多样性，以及开发能够引发针对变异HIV-1毒株的持久保护性免疫力的疫苗的需要。虽然在所有病毒蛋白中都观察到变异，但最大的多样性集中在病毒包膜糖蛋白上，这显然反映了这些蛋白质在引发宿主免疫识别和反应中的主要作用，从而导致包膜蛋白在持续感染期间不断进化。在当前的应用中，我们设计了新型病毒样颗粒（VLP）免疫原，可以优化粘膜和系统性Env特异性免疫反应，以评估恒河猴通过阴道暴露（HIV最常见的途径）免受异源SHIV攻击的保护作用。全球 1 次传输）。我们构建了 DNA 质粒来表达 SHIV 基因序列的 VLP，其中每个 DNA 构建体都从单个 DNA 质粒表达非感染性慢病毒 VLP。每个 VLP 基因插入片段表达 gag、pol、env、vpu、tat 和 rev 基因序列，这些序列由巨细胞病毒立即早期启动子通过质粒 DNA 表达。因此，VLP mRNA 剪接和核输出将受到病毒机制的控制，翻译的蛋白可以有效地从转染细胞中分泌 VLP。 VLP 的骨架中已设计了多种安全突变，以符合美国食品和药物管理局关于人类使用 HIV-1 DNA 疫苗的指南。在该提案中，表达 SHIV VLP 的基因插入片段将从 DNA 中表达。此外，将从转染相同DNA质粒的灵长类细胞的上清液中纯化SHIV VLP。我们建议构建并表征 SHIV VLP-DNA 质粒文库，每个质粒包含不同的 CCR5 (RS) 利用 HIV-1 的 B 型或 C 型包膜糖蛋白。恒河猴将采用初免/加强方案（DNA初免/颗粒加强）进行疫苗接种，以激发体液和细胞免疫，并评估对异源进化枝 B SHIV 攻击的保护作用。该提案的目标是评估和比较具有初级包膜的 VLP 免疫原之间的免疫应答诱导与具有代表共有包膜序列（进化枝 B 或进化枝 C）的包膜的 VLP 免疫原引发的免疫。 SHIV-1 VLP 还将评估其对异源 SHIV 攻击的免疫力和保护作用。使用共有包膜作为天然寡聚体可以将共有包膜引起的保护性免疫与与攻击病毒不匹配的初级寡聚包膜的混合物引起的保护性免疫进行比较。最后，将通过进化枝 B SHIV 攻击来评估由包含代表进化枝 C (Con C) 共有包膜序列的包膜的 SHIV-1 VLP 引发的免疫反应的广度和保护功效。