A Universal Env Immunogen for all HIV-1 Subtypes

适用于所有 HIV-1 亚型的通用包膜免疫原

• 批准号: 6797893
• 负责人: FENG GAO
• 金额: $ 23.1万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-15 至 2006-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6797893
• 关键词: AIDS vaccines; HIV envelope protein; cellular immunity; conformation; guinea pigs; human immunodeficiency virus 1; humoral immunity; immunologic substance development /preparation; laboratory mouse; monoclonal antibody; neutralizing antibody; protein engineering; recombinant virus; vaccine development; vaccinia virus; vector vaccine; virus antigen; virus classification; virus genetics

DESCRIPTION (provided by applicant): HIV genomes are highly variable and have been classified into nine subtypes for most prevalent group M viruses. The genetic divergence among the subtypes can be up to 30%. This high level of genetic variation has become a major hurdle for AIDS vaccine development. To overcome this problem, we have generated a group M consensus (con/con) env gene for all subtypes. The genetic distance between this con/con env gene and any subtype env gene is about the half of that between different subtypes. Western blot and ELISA assays show that the con/con Env protein can bind to the sCD, mAbs and patient sera. The Biacore assay shows that it not only can bind to the neutralizing antibodies and non-neutralizing antibodies but also can undergo conformational changes to bind to 17b mAb as native gp120s. Our preliminary results show that the con/con Env protein expresses linear, discontinuous and glycan antibody epitopes, and it contains cross-reactive epitopes for serum antibodies. Theoretical prediction shows that all well-characterized T cell epitopes and their cleavage sites are preserved on this protein. This data suggests that antibody and CTL epitopes on the con/con Env protein can be processed and presented to the immune system. Therefore, the con/con Env protein may serve as a universal immunogen for all HIV-1 subtypes. In the current proposal we will determine whether such artificially derived proteins can induce broader immune responses than subtype-specific Env immunogens by measuring both cross-clade neutralization activity and cellular immune responses in guinea pigs and mice. The animals will be immunized with naked DNA and then boosted with either rgp120 or recombinant vaccinia viruses (rVV) expressing Env proteins. We will collect serum samples from guinea pigs to determine if higher titers of cross-clade neutralizing antibodies will be elicited by the con/con Env protein, and if humoral immune responses can be further augmented by either rgp120 or rVV. We will also isolate the splenocytes from immunized mice to determine if the con/con Env protein can induce strong cross-clade cellular immune responses alone or with rVV boost by comparing to subtype specific Env immunogens. Results from this study will determine if con/con Env protein can serve as a universal immunogen for all HIV-1 subtypes and will be used as a guideline to design broadly reactive immunization strategies.

描述（由申请人提供）：HIV 基因组变化很大，并且已将最流行的 M 组病毒分为九个亚型。 亚型之间的遗传差异可达30%。 这种高水平的遗传变异已成为艾滋病疫苗开发的主要障碍。 为了克服这个问题，我们为所有亚型生成了 M 组共识 (con/con) env 基因。 该con/con env基因与任何亚型env基因之间的遗传距离约为不同亚型之间遗传距离的一半。 Western blot 和 ELISA 检测表明 con/con Env 蛋白可以与 sCD、mAb 和患者血清结合。 Biacore 测定显示，它不仅可以结合中和抗体和非中和抗体，而且可以发生构象变化，以作为天然 gp120 结合 17b mAb。 我们的初步结果表明，con/con Env 蛋白表达线性、不连续和聚糖抗体表位，并且包含血清抗体的交叉反应表位。 理论预测表明，所有明确表征的 T 细胞表位及其切割位点均保留在该蛋白上。 该数据表明 con/con Env 蛋白上的抗体和 CTL 表位可以被处理并呈递给免疫系统。 因此，con/con Env蛋白可以作为所有HIV-1亚型的通用免疫原。 在当前的提案中，我们将通过测量豚鼠和小鼠的跨进化枝中和活性和细胞免疫反应来确定这种人工衍生的蛋白质是否可以诱导比亚型特异性 Env 免疫原更广泛的免疫反应。 这些动物将用裸露 DNA 进行免疫，然后用 rgp120 或表达 Env 蛋白的重组痘苗病毒 (rVV) 进行加强免疫。 我们将从豚鼠收集血清样本，以确定 con/con Env 蛋白是否会引发更高滴度的跨进化枝中和抗体，以及 rgp120 或 rVV 是否可以进一步增强体液免疫反应。 我们还将从免疫小鼠中分离脾细胞，通过与亚型特异性 Env 免疫原进行比较，以确定 con/con Env 蛋白是否可以单独诱导强烈的跨进化枝细胞免疫反应，或者与 rVV 加强一起诱导。 这项研究的结果将确定 con/con Env 蛋白是否可以作为所有 HIV-1 亚型的通用免疫原，并将用作设计广泛反应性免疫策略的指南。