Genetic immunotherapy for malignancy: murine modeling

描述(由申请人提供)：过继免疫疗法作为恶性肿瘤的第四种治疗方式很有希望，但仍然存在重大障碍，包括肿瘤特异性、效应T细胞功能的维持和最佳激活策略。我们已经开发了一个用抗CD3和抗CD28激活T细胞的系统，然后再进行逆转录病毒转导，以产生表达基因工程的肿瘤特异性受体的T细胞。虽然初步实验显示出治疗前景，但体内此类细胞的动力学、功能和对IL-2的依赖性尚未得到严格研究。基因治疗修饰的原代T细胞在体内表达一种新的肿瘤特异性α/βT细胞受体(TCR)的效果仍有待证实。卵清蛋白在许多系统中已被用作替代肿瘤抗原。我们建议从OT-1T细胞受体转基因小鼠(OT-1TG)中构建编码卵白蛋白特异性T细胞受体α和β基因的双顺反子逆转录病毒表达载体。我们将使用Ly 5.1同基因供者比较基因治疗修饰的T细胞和OT-1 TG T细胞过继转移后的动力学、IL-2依赖性和抗原反应。利用分别转导表达卵清蛋白的小鼠淋巴瘤模型细胞EL-4和白血病模型细胞C1498，检测基因治疗修饰T细胞的治疗效果。这些研究将为未来利用转基因T细胞进行过继免疫疗法治疗淋巴瘤和白血病的临床试验建模提供重要数据。

DESCRIPTION (provided by applicant): Adoptive immunotherapy has great promise as a fourth treatment modality for malignancy, but significant obstacles remain, including tumor specificity, maintenance of effector T cell function and optimal activation strategy. We have developed a system of primary T cell activation with anti-CD3 and anti-CD28 followed by retroviral transduction to generate T cells expressing genetically engineered, tumor-specific receptors. While preliminary experiments show therapeutic promise, the kinetics, function and IL-2 dependence of such cells in vivo has not been rigorously studied. The efficacy of gene-therapy modified primary T cells expressing a new, tumor-specific alpha/beta T cell receptor (TCR) in vivo remains to be demonstrated. Ovalbumin has been used as a surrogate tumor antigen in many systems. We propose to create a bicistronic retroviral expression vector encoding the ovalbumin-specific T cell receptor alpha and beta genes from the OT-1 T cell receptor transgenic mouse (OT-1 Tg). We will use Ly 5.1 congenic donors to compare gene-therapy modified T cells to OT-1 Tg T cells for kinetics, IL-2 dependence and antigen response after adoptive transfer. Using the murine lymphoma model cell line EL-4 and the murine leukemia model cell line C 1498, each transduced to express ovalbumin, we will test the therapeutic efficacy of gene-therapy modified T cells. These studies will provide data important for modeling future clinical trials of adoptive immunotherapy with genetically modified T cells to treat lymphoma and leukemia.