MECHANISMS TO ENHANCE CYTOLYTIC T CELL RESPONSES TO HIV

描述（改编自申请人摘要）：本研究的重点是 增强对HIV-1抗原的细胞溶解反应的机制， 目标是开发一种临床有效的HIV-1疫苗。 两种新型 这些进展是这项研究应用于HIV-1的基础。 (1)一项战略 已经开发了用于将DNA疫苗的基因产物靶向至细胞的DNA疫苗。 进入主要组织相容性II类（MHC）的运输模式 II）用于加工和呈递抗原表位至细胞的途径 辅助性T细胞的免疫反应机制。 这种针对 抗原已显示导致细胞溶解性的显著增强， 对抗原的免疫反应。 (2)用于体内递送的非病毒系统 作为DNA-明胶纳米球凝聚体的基因被应用于 将DNA疫苗递送至抗原呈递细胞，以及 增加辅助性T细胞的Th 1 CD 4+亚群的细胞因子的共递送 从而增强免疫系统的溶细胞性T细胞应答。 的 拟议研究的主要目标是完善这些系统， 以HIV-1 gag蛋白为起始抗原， 这些方法，使他们可以考虑为人类临床 审判 本研究的设计是，首先，制备DNA表达质粒构建体， 编码含有信号的嵌合gag蛋白，跨膜和 LAMP溶酶体膜蛋白的细胞质靶向序列，和 为了测试用质粒作为裸DNA接种的小鼠， 增强抗原向CD 4+辅助性T细胞的呈递， 溶细胞T细胞应答。 实验还将测试对 免疫应答的修饰的gag基因所需的核 在不存在rev基因时mRNA的转运：gag基因构建体 含有INS抑制性不稳定元件突变的猿猴， 逆转录病毒1型组成型转运元件（CTE），或 the two. 接下来，在选择合适的质粒构建体后， 将DNA掺入纳米球中以研究DNA的细胞溶解反应。 与裸DNA相比，用纳米球接种的小鼠， 完善了纳米球制剂作为疫苗的应用。 最后，将测试适当的制剂与以下物质的共递送： 细胞因子，特别是IL-2，IL-12，γ-INF和GMCSF的gag DNA，在 细胞溶解反应的增强。

DESCRIPTION (Adapted from applicant's abstract): This research is focused on mechanisms to enhance the cytolytic response to HIV-1 antigens, with the goal of developing a clinically effective vaccine against HIV-1. Two novel advances underlie the application of this research to HIV-1. (1) A strategy has been developed for targeting gene products of DNA vaccines to a cellular trafficking pattern that accesses the major histocompatibility class II (MHC II) pathway for processing and presentation of antigenic epitopes to the helper T cell arm of the immune response mechanism. This targeting of antigen has been shown to result in a marked enhancement of the cytolytic immune response to the antigen. (2) A non-viral system for in vivo delivery of genes as a DNA-gelatin nanosphere coacervate is being applied for the delivery of the DNA vaccine to antigen-presenting cells, and for the co-delivery of cytokines that augment the Th1 CD4+ subset of helper T cells so as to potentiate the cytolytic T cell response of the immune system. The principle goals of the proposed research are to perfect these systems with the HIV-1 gag protein as the initial antigen, and to prove the feasibility of these approaches so that they may be considered for human clinical trials. The research design is, first, to prepare DNA expression plasmid constructs encoding a chimeric gag protein containing the signal, transmembrane and cytoplasmic targeting sequences of the LAMP lysosomal membrane protein, and to test mice vaccinated with the plasmid as naked DNA for the expected enhanced presentation of the antigen to CD4+ helper T cells and augmented cytolytic T cell response. The experiments also will test the effect on the immune response of modifications of the gag gene required for nuclear transport of the mRNA in the absence of the rev gene: gag gene constructs containing mutations in the INS inhibitory instability elements, the simian retrovirus type 1 constitutive transport element (CTE), or a combination of the two. Next, after selection of the appropriate plasmid construct, the DNA will be incorporated into nanospheres to study the cytolytic response of the mouse vaccinated with nanospheres as compared to naked DNA, and to perfect the nanosphere formulation for this application as a vaccine. Finally, the appropriate formulation will be tested for the co-delivery with gag DNA of cytokines, especially IL-2, IL-12, gamma-INF and GMCSF, in the augmentation of the cytolytic response.