HIV-1 Gene Products/Targeted/MHC II Antigen Presentation

描述(申请人提供)：这个项目的目标是开发一种DNA疫苗配方，有效地刺激免疫反应机制的所有手臂，并适用于人类HIV-1 DNA疫苗。这项研究的新焦点是将抗原作为含有溶酶体膜蛋白(LAMP)序列的嵌合体，该嵌合体将嵌合体运送到主要组织相容II类(MHC II)隔室进行抗原处理和递呈。这种方法旨在增加抗原特异性的CD4+T辅助(Th)淋巴细胞反应，这对最佳CD8+和体液免疫反应至关重要。我们对LAMP/Gag嵌合体疫苗的研究表明，将抗原靶向MHC II隔室导致小鼠所有手臂的免疫反应、抗体、CD4+辅助T细胞和CD8+细胞毒性T细胞显著增加，其中CD4抗体反应的增加是编码野生型抗原的DNA的10-100倍。我们提出的研究有以下具体目标：(1)灵长类动物对LAMP靶向HIV-I Gag的免疫反应正在NIAID的支持下进行，以确定小鼠对编码HIV-1 LAMP/Gag嵌合体的DNA的增强免疫反应是否适用于非人类灵长类动物。我们将合成人LAMP/GAG嵌合体，验证抗原的正确表达和运输，并检测免疫猴子的相关免疫反应。MHC II靶向编码Env、REV、TAT和Nef的DNA疫苗的合成和分析也将被启动，作为可能的人类临床研究的其他候选。(2)树突状细胞特异性蛋白，DC-LAMP和C型凝集素内吞受体，也进入MHC II隔室，表现出与多细胞LAMP靶向系统不同的Gag嵌合体的特性，正在分析可能独特的免疫反应机制，这可能对HIV-1 DNA疫苗配方有价值。(3)腺相关病毒载体(AAV)是最有前景的基因传递载体之一，目前正在与我们的DNA疫苗配方一起进行评估。最初有希望的结果是延长了免疫原性，并增强了对DNA初始AAV Boost方案的抗体反应，这鼓励了继续研究。

DESCRIPTION (provided by applicant):The goals of this project are to develop a DNA vaccine formulation that effectively stimulates all arms of the immune response mechanism and is applicable to a human HIV-1 DNA vaccine. The novel focus of this research is to target the antigen as a chimera containing sequences of the lysosome membrane protein (LAMP) that traffic the chimera to the major histocompatability class II (MHC II) compartment for antigen processing and presentation. This approach is designed to increase antigen-specific CD4+ T-helper (Th) lymphocyte responses that are critical for optimal CD8+and humoral immune responses. Our research with the LAMP/Gag chimera vaccine has shown that targeting of the antigen to the MHC II compartment results in a marked increase in all arms of the immune responses of mice, antibody, CD4+helper T cells, and CD8+cytotoxic T cells, with increases in CD4 antibody responses 10- to 100-fold greater than those resulting from DNA encoding wild type antigen. Our proposed research has the following specific aims: (1) Analysis of primate immune responses to LAMP-targeted HIV-I Gag is being conducted under the auspices of the NIAID to determine if the enhanced immune responses of mice to DNA encoding an HIV-1 LAMP/Gag chimera is applicable to a non-human primate. We will synthesize the human LAMP/Gag chimera, validate the correct expression and trafficking of the antigen, and assay relevant immune responses of the immunized monkeys. The synthesis and analysis of MHC II targeting of DNA vaccines encoding Env, Rev, Tat, and Nef as other candidates for possible human clinical studies will also be initiated. (2) Dendritic cell specific proteins, DC-LAMP and C-type lectin endocytic receptors, that also traffic to the MHC II compartment and demonstrate properties as Gag chimeras that differ from the multicellular LAMP targeting system, are being analyzed for possibly unique immune response mechanisms that may prove of value to a HIV-1 DNA vaccine formulation. (3) Evaluation of adeno-associated virus vector (AAV), one of the most promising gene delivery vehicles, is being conducted with our DNA vaccine formulations. Initial promising results of prolonged immunogenicity and enhanced antibody response to a DNA prime, AAV boost regimen, encourage continued investigation.