DataSheet_1_4-1BB Signaling Boosts the Anti-Tumor Activity of CD28-Incorporated 2nd Generation Chimeric Antigen Receptor-Modified T Cells.docx

While chimeric antigen receptor-modified T (CAR-T) cells have shown great success for the treatment of B cell leukemia, their efficacy appears to be compromised in B cell derived lymphoma and solid tumors. Optimization of the CAR design to improve persistence and cytotoxicity is a focus of the current CAR-T study. Herein, we established a novel CAR structure by adding a full length 4-1BB co-stimulatory receptor to a 28Z-based second generation CAR that targets CD20. Our data indicated that this new 2028Z-4-1BB CAR-T cell showed improved proliferation and cytotoxic ability. To further understand the mechanism of action, we found that constitutive 4-1BB sensing significantly reduced the apoptosis of CAR-T cells, enhanced proliferation, and increased NF-κB pathway activation. Consistent with the enhanced proliferation and cytotoxicity in vitro, this new structure of CAR-T cells exhibited robust persistence and anti-tumor activity in a mouse xenograft lymphoma model. This work provides evidence for a new strategy to optimize the function of CAR-T against lymphoma.

尽管嵌合抗原受体修饰的T细胞（chimeric antigen receptor-modified T cells，CAR-T）在B细胞白血病的治疗中已取得显著成效，但其在B细胞源性淋巴瘤及实体瘤中的治疗效果却明显受限。优化CAR设计以提升T细胞的存续能力与细胞毒性，是当前CAR-T研究的核心方向之一。本研究构建了一种新型CAR结构：在靶向CD20的基于28Z的第二代CAR基础上，融合了全长4-1BB共刺激受体。实验数据显示，该新型2028Z-4-1BB CAR-T细胞的增殖能力与细胞毒性均得到显著增强。为进一步阐明其作用机制，我们发现组成型4-1BB信号感应可显著降低CAR-T细胞的凋亡率、增强其增殖能力，并上调核因子κB（NF-κB）通路的激活水平。与体外实验中观察到的增殖与细胞毒性增强相一致，该新型CAR-T细胞在小鼠异种移植淋巴瘤模型中展现出优异的存续能力与抗肿瘤活性。本研究为优化CAR-T细胞对抗淋巴瘤的功能提供了全新的策略与实验依据。