Optimizing Dual-Targeted and Dual-Armored CAR T Cells for Small Cell LungCancer

摘要 患者自身的T细胞可以利用基因治疗技术来表达受体，称为嵌合体 抗原受体或CARS，允许这些免疫T细胞识别肿瘤细胞表面的蛋白质， 进而允许这些修饰了CAR的T细胞识别并杀死患者自己的肿瘤细胞。这种方法 已经在一些血液系统恶性肿瘤中取得了成功，然而，到目前为止，它在固体方面还没有成功 肿瘤包括小细胞肺癌(SCLC)。小细胞肺癌逃避T细胞介导的两种机制 杀伤是指肿瘤微环境中抗原表达的丧失和T细胞功能的抑制。在……里面 在这项提议中，我们将尝试通过设计针对两种SCLC抗原的CAR T细胞来克服这些障碍 同时，这会产生多种因素(“盔甲”)，增强实体肿瘤中T细胞的活性。我们 假设这些双装甲、双靶向(DADT)CAR T细胞将更有效地对抗小细胞肺癌 比以前的T细胞介导和免疫疗法更有效。我们之前已经表明，CAR T细胞的靶向是 GD3抗原或DLL3抗原，这两种抗原都表达在大多数小细胞肺上 癌症，能够杀死临床前系统中的小细胞肺癌细胞。此外，我们还开发了多个 分泌IL-18或抗体衍生的单链可变片段等因子的装甲CAR T细胞 阻断免疫检查点受体PD-1的单链抗体，或阻断吞噬抑制信号的单链抗体 肿瘤细胞表面CD47的表达。所有这些盔甲通过增强体内模型系统中CAR T细胞的活性 不同的机制。在本提案的目标1中，我们将生成针对DLL3和GD3的CAR T细胞 同时，克服肿瘤中的抗原异质性和抗原丢失作为逃避T细胞的一种手段 细胞介导的杀戮。同时，在目标2中，我们将测试一对盔甲，以确定最多的一对 单抗原靶向CAR T细胞体内抗小细胞肺癌作用的研究 免疫系统。然后我们分析了以下小细胞肺癌肿瘤微环境中的免疫细胞 CAR T细胞治疗评估由装甲CAR T细胞介导的变化。最终，在目标3中，我们将 将这些方法结合起来，可以产生识别GD3和DLL3的CAR T细胞，并产生多种盔甲。 这些用于小细胞肺癌的DADT CAR T细胞可能适合于进一步的临床前试验，为临床试验做准备 超出了本提案的范围，代表了小细胞肺癌的一种新的治疗方法。考虑到我们强大的赛道 记录在CAR T细胞临床翻译中，我们完全期待有新的CAR T细胞适合临床试验 资金到位的结论。此外，这些新颖的CAR T细胞可能被用作探索相互作用的工具 T细胞和小细胞肺癌微环境之间的关系。小细胞肺癌放射治疗后肿瘤细胞的变化分析 本文提出的装甲车T细胞可能揭示小细胞肺癌生物学的新方面，并阐明其机制。 小细胞肺癌的免疫逃逸和治疗失败。

ABSTRACT A patient's own T cells can be modified using gene therapy technology to express receptors, termed chimeric antigen receptors or CARs, which allow these immune T cells to recognize proteins on the tumor cell surface, and in turn allow these CAR modified T cells to recognize and kill the patient's own tumor cells. This approach has been successful in some hematological malignancies, however, it has not been successful to date in solid tumors including small cell lung cancer (SCLC). Two mechanisms by which SCLC may evade T cell-mediated killing are loss of expression of antigens, and suppression of T cell function in the tumor microenvironment. In this proposal, we will attempt to overcome these barriers by designing CAR T cells that target two SCLC antigens simultaneously, and that produce multiple factors (“armors”) that enhance T cell activity in solid tumors. We hypothesize that these dual-armored, dual targeted (DADT) CAR T cells will be more effective against SCLC than previous T cell-mediated and immune therapies. We have previously shown that CAR T cells targeted to either the antigen GD3 or to the antigen DLL3, both of which are expressed on the majority of small cell lung cancers, are capable of killing SCLC cells in preclinical systems. Additionally, we have developed multiple armored CAR T cells that secrete factors such as IL-18, or an antibody-derived single-chain variable fragment (scFv) that blocks the immune checkpoint receptor PD-1, or an scFv blocking the phagocytosis-inhibitory signal CD47 on tumor cells. All of these armors enhance CAR T cell activity in our in vivo model systems through different mechanisms. In Aim 1 of this proposal, we will generate CAR T cells targeting DLL3 and GD3 simultaneously, to overcome antigen heterogeneity and antigen loss in tumors as a means of escape from T cell-mediated killing. Simultaneously, in Aim 2, we will test pairs of armors to identify the pair that is the most effective at enhancing the activity of single antigen-targeted CAR T cells against SCLC in vivo in immunocompetent systems. We then analyze the immune cells in the SCLC tumor microenvironment following CAR T cell treatment to assess changes mediated by the armored CAR T cells. Ultimately, in Aim 3, we will combine these approaches to generate CAR T cells that recognize GD3 and DLL3 and produce multiple armors. These DADT CAR T cells for SCLC may be suitable for further preclinical testing in preparation for clinical trials beyond the scope of this proposal, representing a novel therapeutic approach to SCLC. Given our robust track record in CAR T cell clinical translation, we fully anticipate having new CAR T cells suitable for clinical trials at the conclusion of funding. Additionally, these novel CAR T cells may be used as tools to explore the interactions between T cells and the SCLC microenvironment. The analysis of changes in SCLC tumors induced by the armored CAR T cells proposed here may reveal novel aspects of SCLC biology and illuminate mechanisms of immune escape and treatment failure in SCLC.