SALMONELLA GP120 DNA VACCINE VECTOR

沙门氏菌 GP120 DNA 疫苗载体

• 批准号: 6658272
• 负责人: David Michael Hone
• 金额: $ 27.48万
• 依托单位: UNIVERSITY OF MD BIOTECHNOLOGY INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6658272
• 关键词: AIDS vaccines; HIV envelope protein gp120; HIV infections; Salmonella typhi; clinical research; disease /disorder model; drug screening /evaluation; human immunodeficiency virus 1; human tissue; laboratory mouse; vaccine development; vector vaccine

The tropism of Salmonella for dendritic cells and macrophages in the lymphoid tissue of the intestinal mucosal surface, naturally targets attenuated derivatives of this organism to these inductive sites and allows for the exploitation of this property in the development of a mucosal HIV- 1 DNA vaccine. Accordingly, we and others have recently reported that genetically-engineered, attenuated Salmonella strains are capable of delivering DNA vaccines to mouse tissues where they elicit humoral and cell-mediated immune responses against passenger antigens encoded by the DNA vaccine. Preliminary data generated in our laboratory also suggests that a single oral dose of a Salmonella HIGV-1 Env DNA vaccine induces similar numbers of interferon-gamma-secreting CD8+ T cells as those induced by the naked Env DNA vaccine injected intramuscularly as a single mug dose. The principle objective of this project is to obtain preclinical data on the safety and immunogenicity of HIV-1 Env DNA vaccines delivered by attenuated Salmonella in animal models. This data is required by Project 3 to test the principal hypothesis on our IPCAVD program that such vaccines are safe and immunogenic in human volunteers. We will obtain this data in the following specific aims: 1) to construct and characterize a prototype attenuated Salmonella typhi HIV-1 gp120 DNA vaccine vector: We will construct two HIV-1/Ba-L gp120 DNA vaccines and introduce them into our attenuated Salmonella typhi vector strain, CVD DELTA/ASD. The first will be comprised of a gp120 DNA vaccine of the HIV-1-Ba-L isolate (gp120Ba-L). This gp120 has been codon-optimized for expression in mammalian cells. The second will be compromised of a chimeric gene encoding a gp120-CD4 fusion protein that is expected to prime for broadly neutralizing antibodies against HIV-11 (see also Project 2); and 2) to obtain preclinical safety, immunogenicity and genetic toxicity data on the Salmonella HIV-1 DNA vaccines developed in aim 1. In the second phase of this study we will obtain preclinical safety, immunogenicity and genetic toxicity data on the Salmonella HIV-1 DNA vaccine vector constructs. Although Salmonella typhi is only fully virulent in humans, murine models have been developed for the assessment live lymphoid vaccine safety and immunogenicity. The information gained from these studies will be used in IND applications to conduct Phase 1 safety and immunogenicity studies in volunteers as described in Project 3.

沙门氏菌对肠粘膜表面淋巴组织中的树突状细胞和巨噬细胞的趋向性，自然地将这种生物体的减毒衍生物靶向这些诱导位点，并允许在粘膜HIV-1 DNA疫苗的开发中利用这一特性。因此，我们和其他人最近报道了基因工程减毒沙门氏菌菌株能够将 DNA 疫苗递送至小鼠组织，在小鼠组织中它们引发针对 DNA 疫苗编码的过客抗原的体液和细胞介导的免疫反应。我们实验室产生的初步数据还表明，单次口服剂量的沙门氏菌 HIGV-1 Env DNA 疫苗诱导的分泌干扰素 γ 的 CD8+ T 细胞数量与肌内注射单剂量裸 Env DNA 疫苗诱导的数量相似。该项目的主要目标是获得关于减毒沙门氏菌在动物模型中提供的 HIV-1 Env DNA 疫苗的安全性和免疫原性的临床前数据。项目 3 需要这些数据来测试我们的 IPCAVD 计划的主要假设，即此类疫苗在人类志愿者中是安全的且具有免疫原性。我们将通过以下具体目标获得这些数据：1）构建并表征减毒伤寒沙门氏菌 HIV-1 gp120 DNA 疫苗载体原型：我们将构建两种 HIV-1/Ba-L gp120 DNA 疫苗并将其引入我们的减毒伤寒沙门氏菌载体菌株 CVD DELTA/ASD 中。第一个疫苗将包含 HIV-1-Ba-L 分离株 (gp120Ba-L) 的 gp120 DNA 疫苗。该 gp120 已针对在哺乳动物细胞中的表达进行了密码子优化。第二个将受到编码 gp120-CD4 融合蛋白的嵌合基因的影响，预计该基因将广泛中和针对 HIV-11 的抗体（另见项目 2）； 2) 获得目标 1 中开发的沙门氏菌 HIV-1 DNA 疫苗的临床前安全性、免疫原性和遗传毒性数据。在本研究的第二阶段，我们将获得沙门氏菌 HIV-1 DNA 疫苗载体构建体的临床前安全性、免疫原性和遗传毒性数据。尽管伤寒沙门氏菌仅对人类具有完全毒性，但已开发出小鼠模型用于评估活淋巴疫苗的安全性和免疫原性。从这些研究中获得的信息将用于 IND 申请，以在志愿者中进行第一阶段安全性和免疫原性研究，如项目 3 中所述。