CTLA-4尾部融合增强CAR-T抗肿瘤免疫

2023-08-07 09:24

这些发现阐明了通过与其他细胞工程技术正交的方式来以合成CCT融合的方式来产生治疗性T细胞和改善CAR-T功能的独特策略。

SCI

6 August 2023

CTLA-4 tail fusion enhances CAR-T antitumor Immunity

(Nature Immunology, IF: 30.5)

Xiaoyu Zhou, Hanbing Cao, Shao-Yu Fang, Ryan D. Chow, Kaiyuan Tang, Medha Majety, Meizhu Bai, Matthew B. Dong, Paul A. Renauer, Xingbo Shang, Kazushi Suzuki, Andre Levchenko & Sidi Chen

CORRESPONDENCE TO: sidi.chen@yale.edu

Chimeric antigen receptor (CAR)-T cells are powerful therapeutics; however, their efficacy is often hindered by critical hurdles. Here utilizing the endocytic feature of the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) cytoplasmic tail, we reprogram CAR function and substantially enhance CAR-T efficacy in vivo. CAR-T cells with monomeric, duplex or triplex CTLA-4 cytoplasmic tails (CCTs) fused to the C terminus of CAR exhibit a progressive increase in cytotoxicity under repeated stimulation, accompanied by reduced activation and production of proinflammatory cytokines. Further characterization reveals that CARs with increasing CCT fusion show a progressively lower surface expression, regulated by their constant endocytosis, recycling and degradation under steady state. The molecular dynamics of reengineered CAR with CCT fusion results in reduced CAR-mediated trogocytosis, loss of tumor antigen and improved CAR-T survival. CARs with either monomeric (CAR-1CCT) or duplex CCTs (CAR-2CCT) have superior antitumor efficacy in a relapsed leukemia model. Single-cell RNA sequencing and flow cytometry analysis reveal that CAR- 2CCT cells retain a stronger central memory phenotype and exhibit increased persistence. These findings illuminate a unique strategy for engineering therapeutic T cells and improving CAR-T function through synthetic CCT fusion, which is orthogonal to other cell engineering techniques.

嵌合抗原受体（CAR）-T细胞是强大的治疗手段；然而，它们的功效往往受到关键阻碍。此处我们利用细胞毒性T淋巴细胞相关抗原-4（CTLA-4）细胞质尾部的内吞特征，我们重新编码CAR功能，并在体内显著增强CAR-T功效。具有与CAR的C末端融合的单体、双链或三链CTLA-4胞质尾部（CCTs）的CAR-T细胞在重复刺激下表现出细胞毒性的逐渐增加，同时伴有减少促炎细胞因子的激活和产生。进一步的表征表明，随着CCT融合的增加，CAR的表面表达逐渐降低，这是由其在稳定状态下不断的内吞、循环和降解所调节的。用CCT融合重建CAR的分子动力学导致CAR介导的胞嘧啶作用的减少、肿瘤抗原的损失和提高CAR-T的存活率。具有单体（CAR-1CCT）或双体（CAR-2CCT）的CAR在复发性白血病模型中具有优越的抗肿瘤功效。单细胞RNA测序和流式细胞术分析表明，CAR-2CCT细胞保留了更强的中枢记忆表型，并表现出更强的持久性。这些发现阐明了通过与其他细胞工程技术正交的方式来以合成CCT融合的方式来产生治疗性T细胞和改善CAR-T功能的独特策略。