PLASMID DNA TO INDUCE IMMUNITY TO INTRACELLULAR PATHOGEN

通过注射裸质粒DNA作为“免疫原”来控制传染病的免疫方法已经在有限数量的病毒模型中进行了测试，这些初步研究的结果引起了很大的兴奋。质粒DNA免疫有望提供一种刺激体液和细胞免疫反应的独特方法，它代表了传统疫苗开发方法的一种有吸引力的替代方案。事实上，诱导特定细胞介导的免疫反应的能力是一种系统，在许多临床可接受的疫苗配方中，这是一个未实现的目标。这是疫苗开发中的关键考虑因素，因为细胞介导的免疫反应是消除大多数细胞内病原体所必需的。在我们的第一阶段研究中，我们成功地证明了利用编码毒力因子的质粒DNA进行基因免疫可以诱导对细胞内单核细胞增多性李斯特菌的免疫。这种免疫导致了体外测量的细胞毒细胞的发展，并对存活的单核细胞增多性乳杆菌的攻击产生了保护性免疫。在我们提议的第二阶段研究中，我们将扩展这些研究，以优化和验证这一有前景的方法的使用，以发展对兼性细胞内病原体的保护性细胞介导性免疫。拟议的商业应用：用于控制许多感染性病原体的疫苗仍有待开发。最值得注意的是，缺乏能够导致对细胞内病原体产生保护性细胞介导免疫的疫苗。需要开发改进的遗传免疫试剂，因为这项技术适用于对兼性细胞内寄生虫的有效免疫。

The method of immunization for the control of infectious diseases in which naked plasmid DNA is injected as the "immunogen" has been tested in a limited number of viral models and the results of these initial studies have caused much excitement. Plasmid DNA immunization promises to offer a unique method of stimulating both humor and cellular immune responses and it represents an attractive alternative to conventional approaches of vaccine development. Indeed, the ability to indue a specific cell-mediated immune response is a system an unfulfilled goal of many vaccine formulations acceptable for clinical use. This is critical consideration in vaccine development, as a cell-mediated immune response is required for the elimination of most intracellular pathogens. In our Phase I study w4e successful demonstrated that immunity to the intracellular pathogen Listeria monocytogenes can be induced by genetic immunization using plasmid DNA encoding a virulence factor for immunization. This immunization lead to the development of cytotoxic cells as measured in vitro and to protective immunity against challenge with viable L. monocytogenes. In our proposed Phase II studies we will expand these studies in order to optimize and validate the use of this promising approach to develop protective cell-mediated immunity to facultative intracellular pathogens. PROPOSED COMMERCIAL APPLICATION: Vaccines for the control of many infectious agents remain to be developed. Most notable is the absence of vaccines that can cause the development of protective cell-mediated immunity to intracellular pathogens. Development of improved reagents for genetic immunization is required as is the demonstration that this technology is suitable for effective immunization against facultative intracellular parasites.