Chimeric antigen receptor T (CAR-T) cells targeting multiple antigens, may reduce the risk of immune escape following the loss of the target antigen and further increase the efficacy of treatment. We developed dual-targeting CAR-T cells that target CD19 and CD37 antigens and evaluated their antitumor effects. CD19/CD37 dual CAR-T cells were generated using co-transduction and simultaneous gene transfer of two types of lentiviral vectors transferring CD19CAR or CD37CAR genes, including the intracellular domains of CD28 and CD3ζ signaling domains. These dual CAR-T cells contained three fractions: CD19/CD37 bispecific CAR-T cells, single CD19CAR-T cells, and single CD37CAR-T cells. In the functional evaluation of CAR-T cells in vitro, CD19/CD37 dual CAR-T cells showed adequate proliferation and cytokine production in response to CD19 and CD37 antigen stimulation alone or in combination. Evaluation of intracellular signaling revealed that dual CAR-T cell-mediated signals were comparable to single CAR-T cells in response to CD19 and CD37 positive B Cell tumors. Although the cytotoxicity of CD19/CD37 dual CAR-T cells in both CD19 and CD37 positive B cell tumors was similar to that of single CD19 and CD37CAR-T cells, against CD19 and CD37 antigen-heterogeneous tumor, dual CAR-T cells demonstrated significantly superior tumor lysis compared with single CAR-T cells. Furthermore, CD19/CD37 dual CAR-T cells effectively suppressed antigen-heterogeneous Raji cells in a xenograft mouse model. Collectively, these results suggest that CD19/CD37 dual CAR-T cells may be effective target-antigen-loss B-cell tumor models in vitro and in vivo, which represents a promising treatment for patients with relapsed/refractory B-cell malignancies.

中文翻译：

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靶向 CD19 和 CD37 的双 CAR-T 细胞在靶抗原丢失 B 细胞肿瘤模型中有效。

靶向多种抗原的嵌合抗原受体 T (CAR-T) 细胞可以降低靶抗原丢失后免疫逃逸的风险，并进一步提高治疗效果。我们开发了针对 CD19 和 CD37 抗原的双靶向 CAR-T 细胞，并评估了其抗肿瘤效果。CD19/CD37双CAR-T细胞是通过两种类型的慢病毒载体的共转导和同时基因转移产生的，所述慢病毒载体转移CD19CAR或CD37CAR基因，包括CD28和CD3ze信号结构域的胞内结构域。这些双 CAR-T 细胞包含三个部分：CD19/CD37 双特异性 CAR-T 细胞、单个 CD19CAR-T 细胞和单个 CD37CAR-T 细胞。在体外CAR-T细胞的功能评估中，CD19/CD37双CAR-T细胞在单独或联合刺激CD19和CD37抗原时表现出足够的增殖和细胞因子产生。细胞内信号传导评估显示，双 CAR-T 细胞介导的信号与单 CAR-T 细胞对 CD19 和 CD37 阳性 B 细胞肿瘤的反应相当。尽管CD19/CD37双CAR-T细胞在CD19和CD37阳性B细胞肿瘤中的细胞毒性与单CD19和CD37CAR-T细胞相似，但针对CD19和CD37抗原异质肿瘤，双CAR-T细胞表现出显着的细胞毒性。与单个 CAR-T 细胞相比，具有更好的肿瘤溶解能力。此外，CD19/CD37双CAR-T细胞在异种移植小鼠模型中有效抑制抗原异质Raji细胞。总的来说，这些结果表明 CD19/CD37 双 CAR-T 细胞可能是体外和体内有效的靶抗原丢失 B 细胞肿瘤模型，这为复发/难治性 B 细胞恶性肿瘤患者提供了一种有前景的治疗方法。