Chang Hyeyoun, Foulke John G, Chen Luping, Tian Fang, Gu Zhizhan
American Type Culture Collection (ATCC), Manassas, VA 20110, USA.
Cancers (Basel). 2024 May 22;16(11):1965. doi: 10.3390/cancers16111965.
Recent studies highlight the integral role of the interferon gamma receptor (IFNγR) pathway in T cell-mediated cytotoxicity against solid but not liquid tumors. IFNγ not only directly facilitates tumor cell death by T cells but also indirectly promotes cytotoxicity via myeloid phagocytosis in the tumor microenvironment. Meanwhile, full human ex vivo immune checkpoint drug screening remains challenging. We hypothesized that an engineered gamma interferon activation site response element luciferase reporter (GAS-Luc2) can be utilized for immune checkpoint drug screening in diverse ex vivo T cell-solid tumor cell co-culture systems. We comprehensively profiled cell surface proteins in ATCC's extensive collection of human tumor and immune cell lines, identifying those with endogenously high expression of established and novel immune checkpoint molecules and binding ligands. We then engineered three GAS-Luc2 reporter tumor cell lines expressing immune checkpoints PD-L1, CD155, or B7-H3/CD276. Luciferase expression was suppressed upon relevant immune checkpoint-ligand engagement. In the presence of an immune checkpoint inhibitor, T cells released IFNγ, activating the JAK-STAT pathway in GAS-Luc2 cells, and generating a quantifiable bioluminescent signal for inhibitor evaluation. These reporter lines also detected paracrine IFNγ signaling for immune checkpoint-targeted ADCC drug screening. Further development into an artificial antigen-presenting cell line (aAPC) significantly enhanced T cell signaling for superior performance in these ex vivo immune checkpoint drug screening platforms.
近期研究突显了干扰素γ受体（IFNγR）通路在T细胞介导的针对实体瘤而非液体肿瘤的细胞毒性中的重要作用。IFNγ不仅直接促进T细胞介导的肿瘤细胞死亡，还通过肿瘤微环境中的髓系吞噬作用间接促进细胞毒性。与此同时，完整的人源体外免疫检查点药物筛选仍然具有挑战性。我们假设一种工程化的γ干扰素激活位点反应元件荧光素酶报告基因（GAS-Luc2）可用于多种体外T细胞-实体瘤细胞共培养系统中的免疫检查点药物筛选。我们全面分析了美国典型培养物保藏中心（ATCC）大量人肿瘤和免疫细胞系中的细胞表面蛋白，确定了那些内源性高表达已确立和新型免疫检查点分子及结合配体的细胞系。然后，我们构建了三种表达免疫检查点PD-L1、CD155或B7-H3/CD276的GAS-Luc2报告基因肿瘤细胞系。当相关免疫检查点配体结合时，荧光素酶表达受到抑制。在存在免疫检查点抑制剂的情况下，T细胞释放IFNγ，激活GAS-Luc2细胞中的JAK-STAT通路，并产生可量化的生物发光信号用于抑制剂评估。这些报告基因细胞系还检测到用于免疫检查点靶向抗体依赖的细胞介导的细胞毒性（ADCC）药物筛选的旁分泌IFNγ信号。进一步开发成人工抗原呈递细胞系（aAPC）可显著增强T细胞信号，从而在这些体外免疫检查点药物筛选平台中实现卓越性能。
