Translational linkage strategies for DNA vaccines against cancer

描述（由申请人提供）：本项目的目标是开发有效的分子定义的免疫佐剂，用于针对癌症的主动免疫，并与针对感染性病原体的免疫的更有效的免疫佐剂直接相关。虽然对癌症的耐受性是可逆的，但针对癌症自身抗原的免疫面临与耐受性和免疫调节相关的实质性障碍。有效的免疫佐剂对于针对固有地免疫原性差的癌症自身抗原的成功主动免疫是必要的。最近，我们已经获得的数据表明，在用基因融合佐剂免疫的动物中，来自适应性免疫应答的细胞的稳健活化。我们使用遗传佐剂（质粒DNA），其结合联合收割机微生物基因，包括VP 22（疱疹病毒）和外毒素A（铜绿假单胞菌），与优化的自身抗原（酪氨酸酶相关蛋白1 = TYRP 1），以产生增强协同和高效免疫应答的融合基因产物。基于广泛的初步筛选和我们对这些分子如何调节获得性免疫细胞活化的理解，已经仔细选择了编码各种候选微生物基因融合体的DNA。将引发免疫细胞最有效活化的微生物基因融合佐剂组合到单个质粒上，通过来自口蹄疫病毒（FMDV）的18个氨基酸的“2A序列”连接，以产生双顺反子DNA疫苗。具体目的1检查与单个基因融合体相比，组合由2A序列偶联的两个或更多个基因融合体是否可以增加免疫细胞活化的水平。具体目标2研究了最有效的2A连锁基因融合嵌合体的T细胞活化机制。具体目标3评估多拷贝DNA微生物融合疫苗作为可与IL-12/Fc融合DNA构建体一起应用以对抗不同肿瘤的组合药剂是否有效。

DESCRIPTION (provided by applicant): The goal of this project is to develop effective molecularly-defined immune adjuvants for active immunization against cancer, and with direct relevance for more potent immune adjuvants for immunization against infectious pathogens. Although tolerance to cancer is reversible, immunization against cancer self-antigens faces substantial hurdles related to tolerance and immune regulation. Potent immune adjuvants will be necessary for successful active immunization against cancer self-antigens, which are inherently poorly immunogenic. Recently, we have acquired data that demonstrates robust activation of cells from the adaptive immune response in animals immunized with gene-fusion adjuvants. We use genetic adjuvants (plasmid DNA) that combine microbial genes, including VP22 (Herpesvirus) and Exotoxin A (Pseudomonas aeruginosa), with an optimized self-antigen (tyrosinase-related protein 1 = TYRP1) to generate fusion gene products that potentiate a synergistic and highly effectual immune response. DNA encoding a variety of candidate microbial gene-fusions have been carefully selected based on extensive preliminary screening and on our understanding of how these molecules regulate the activation of acquired immune cells. The microbial gene-fusion adjuvants that elicit the most potent activation of immune cells will be combined onto a single plasmid, linked by an 18 amino acid "2A sequence" from the foot-and-mouth disease virus (FMDV), to generate a bicistronic DNA vaccine. Specific Aim 1 examines whether combining two or more gene-fusions coupled by the 2A sequence can increase the level of immune cell activation compared to a single gene-fusion. Specific Aim 2 studies the mechanism of T-cell activation from the most potent 2A-linked gene-fusion chimeras. Specific Aim 3 evaluates whether multi-copy DNA microbial fusion vaccines are effective, as combinatorial agents that can be applied with an IL-12/Fc fusion DNA construct against different tumors.