IMMUNOTHERAPY WITH ELECTROFUSED DENDRITIC TUMOR HYBRIDS

电融合树突状肿瘤杂交体的免疫治疗

• 批准号: 6658985
• 负责人: SUYU SHU
• 金额: $ 33.3万
• 依托单位: CLEVELAND CLINIC FOUNDATION
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-01 至 2004-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6658985
• 关键词: antigen presentation; beta galactosidase; biomedical equipment development; cell fusion; colony stimulating factor; dendritic cells; disease /disorder model; electric field; hybrid cells; interleukin 4; ionophores; laboratory mouse; model design /development; neoplasm /cancer immunotherapy; neoplasm /cancer vaccine; neoplastic cell; nonhuman therapy evaluation; vaccine development

DESCRIPTION: (Applicant's Abstract) The efficacy of cancer immunotherapy depends highly on the potency and duration of the induced immune response. To date, cancer vaccinations have utilized intact tumor cells, naive proteins, CTL-defined peptides, nucleic acids, cell membranes and recombinant viruses as well as genetically modified tumors. Although some approaches have been to increase the antigen presenting capacity of tumor cells, in most cases, the dominant role of host antigen-presenting cells (APCs) has been demonstrated. Among various APCs, dendritic cells (DCs) seem to have the essential properties required for eliciting T-cell responses: migration and homing, antigen processing and presentation and co-stimulation. Recently, DCs have been used to present tumor antigens. This is generally achieved by pulsing DCs with peptides, tumor lysates or RNA derived from neoplastic cells. It has also been demonstrated that immunization with DC-tumor fused chimeric cells results in the regression of established metastases. Fused cells should have the ability to elicit both MHC class I and II-restricted responses by processing and presenting known and undefined tumor antigens. In most reported cases, however, fusion has been accomplished with the use of PEG, resulting in low efficiency and high toxicity. With this approach, it may be the technical rather than conceptual aspects that limit its application. The applicant has recently demonstrated that fusion of DCs and tumor cells by applying electric field pulses is at least 10-fold more efficient than that by PEG. Interestingly, electrofusion of immature DCs with tumor cells resulted in hybrid cells having characteristics of mature DCs with high expression of MHC class II, B7.1 and B7.2 molecules. To analyze biological and immunological functions of these artificially generated chimeric cells, the current application will utilize the well-characterized model tumor-associated antigen, B-galactosidase, to address fundamental issues. Subsequent experiments will use several weakly and poorly immunogenic tumors. The goal of the current application is to develop in murine models, the principles and methodologies for utilizing DCs fused with entire tumor cells for active and adoptive immunotherapy of cancer. The specific aims are: 1) To optimize electrofusion techniques; 2) To characterize antigen processing and presentation, MHC restriction and trafficking patterns of fused cells; 3) To analyze characteristics of immune responses elicited by DC-tumor fused cells; 4) To explore the therapeutic potential of the chimeric cells; and 5) To develop methods for primary in vitro immunization for generating tumor-specific T cells.

描述：（申请人摘要）癌症免疫疗法的功效 很大程度上取决于诱导的免疫反应的效力和持续时间。到 迄今为止，癌症疫苗接种利用了完整的肿瘤细胞、天然蛋白质、 CTL定义的肽、核酸、细胞膜和重组病毒为 以及转基因肿瘤。尽管一些方法已经 增加肿瘤细胞的抗原呈递能力，在大多数情况下， 宿主抗原呈递细胞（APC）的主导作用已被证明。 在各种 APC 中，树突状细胞 (DC) 似乎具有以下基本特性 引发 T 细胞反应所需：迁移和归巢、抗原 处理和呈现以及共同刺激。最近，DC已被用于 呈现肿瘤抗原。这通常是通过脉冲直流来实现的 来自肿瘤细胞的肽、肿瘤裂解物或RNA。也曾被 证明用 DC 肿瘤融合嵌合细胞进行免疫会导致 已形成转移的消退。融合细胞应该具备的能力 通过处理和引发 MHC I 类和 II 类限制性反应 呈现已知和未定义的肿瘤抗原。然而，在大多数报道的案例中， 使用PEG完成融合，效率低 且毒性高。通过这种方法，它可能是技术性的而不是 限制其应用的概念方面。申请人最近 证明通过施加电场使树突状细胞和肿瘤细胞融合 脉冲的效率比 PEG 至少高 10 倍。有趣的是， 未成熟 DC 与肿瘤细胞的电融合产生了具有以下特征的杂交细胞： 高表达 MHC II 类、B7.1 和 B7.1 的成熟 DC 的特征 B7.2分子。分析这些物质的生物学和免疫功能 人工生成的嵌合细胞，当前的应用将利用 充分表征的模型肿瘤相关抗原 B-半乳糖苷酶，以解决 根本问题。后续的实验会使用一些弱的和差的 免疫原性肿瘤。当前应用的目标是在小鼠中开发 模型、利用DC与整个系统融合的原理和方法 用于癌症主动和过继免疫治疗的肿瘤细胞。具体目标 是：1）优化电熔技术； 2) 表征抗原 融合蛋白的加工和呈现、MHC 限制和贩运模式 细胞； 3) 分析DC肿瘤引起的免疫反应特征 融合细胞； 4）探索嵌合细胞的治疗潜力；和 5) 开发初级体外免疫方法以产生 肿瘤特异性T细胞。