NOVEL TECHNOLOGIES APPLIED TO A DENQUE DNA VACCINE

登革热病毒在世界热带地区造成重大的公共卫生负担，现在威胁到在更温和的气候中扩散。 目前还没有可接受的疫苗来预防登革热。 该项目旨在开发预防登革热的DNA疫苗。 现有的登革DNA疫苗构建体将通过向疫苗质粒上的登革基因添加溶酶体相关膜蛋白（LAMP）的细胞内运输序列来改进。这些序列将抗原靶向与MHC II类相关的细胞内区室，并增强接种动物的免疫应答。 疫苗将通过在由聚（磷酸酯）和其他正在开发的聚合物制成的缓释微球中递送质粒来进一步改进。 预计这些制剂将提高DNA免疫的效率，减少所需的剂量。 微球还将用于共同递送粒细胞-巨噬细胞集落刺激因子（GMCSF）和选择的其他细胞因子以增强适当的免疫应答。将在非人灵长类动物研究中检测在小鼠中有效诱导中和抗体的制剂。最有可能在人类中成功的候选物的选择将基于疫苗诱导免疫力的能力来进行，所述免疫力在用活登革病毒攻击后防止非人灵长类动物中的病毒血症。 该项目的结果将用于选择进入人体试验GMP生产的疫苗制剂。

Dengue viruses cause a significant public health burden in tropical regions of the world and now threaten to proliferate in more temperate climates. There is currently no acceptable vaccine to prevent dengue. This project seeks to develop a DNA vaccine that will prevent dengue fever. Existing dengue DNA vaccine constructs will be improved by the addition of the intracellular trafficking sequences of the lysosome associated membrane protein (LAMP) to dengue genes on the vaccine plasmid. These sequences target the antigen to MHC class II associated intracellular compartments and enhance the immune response of vaccinated animals. The vaccines will be further improved by delivering plasmids in sustained release microspheres made from poly(phosphoester) and other polymers under development. These preparations are expected to increase the efficiency of DNA immunization and reduce the number of doses required. The microspheres will also be used to co-deliver granulocyte- macrophage colony stimulating factor (GMCSF) and other cytokines selected to enhance the appropriate immune response. Formulations that are effective in inducing neutralizing antibodies in mice will be tested in non-human primate studies. Selection of the candidates most likely to succeed in humans will be made based on the ability of vaccines to induce immunity that prevents viremia in non-human primates after challenge with live dengue virus. The results of this project will be directed to a vaccine formulation chosen to enter GMP production for human trials.