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基因组高度可变，对于最流行的M组病毒，已将其分为9种亚型。 亚型之间的遗传差异可高达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，我们已经为所有亚型产生了M组共有（con/con）env基因。 这种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蛋白能与sCD、mAb和患者血清结合。 Biacore分析表明，它不仅可以与中和抗体和非中和抗体结合，而且可以经历构象变化，以天然gp 120的形式与17 b mAb结合。 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，它包含血清抗体的交叉反应表位。 理论预测表明，所有良好表征的T细胞表位和它们的切割位点都保留在该蛋白上。 该数据表明，con/con Env蛋白上的抗体和CTL表位可以被加工并呈递给免疫系统。 因此，con/con Env蛋白可以作为所有HIV-1亚型的通用免疫原。 在本提案中，我们将通过测量豚鼠和小鼠中的交叉进化枝中和活性和细胞免疫应答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应答。 用裸DNA免疫动物，然后用rgp 120或表达Env蛋白的重组牛痘病毒（rVV）加强免疫。 我们将收集豚鼠的血清样本，以确定con/con Env蛋白是否会引起更高滴度的交叉进化枝中和抗体，以及rgp 120或rVV是否可以进一步增强体液免疫应答。 我们还将从免疫的小鼠中分离脾细胞，以通过与亚型特异性Env免疫原比较来确定con/con Env蛋白是否可以单独或与rVV加强一起诱导强的交叉进化枝细胞免疫应答。 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。