CD33 KO -CD33-mesothelin Loop CAR design avoids fratricide and improves efficacy of iNK cells against acute myeloid leukemia

作者：Yao Wang, Xiujuan Zheng, Zhiqian Wang, Ziyun Xiao, Yunqing Lin, Fan Zhang, Yanhong Liu, Pengcheng Liu, Qitong Weng, Leqiang Zhang, Chengxiang Xia, Dehao Huang, Lijuan Liu, Yanping Zhu, Qi Zhang, Hanmeng Qi, Yi Chen, Yiyuan Shen, Chenyuan Zhang, Jiacheng Xu, Yaoqin Zhao, Jiaxin Wu, Tongjie Wang, Mengyun Zhang, Minming Li, Wenbin Qian, Aibin Liang, Xin Du, Wenyu Yang, Tianyuan Hu, Quan Chen, Xiaofan Zhu, Fangxiao Hu, Jinyong Wang · 发表于：Journal for ImmunoTherapy of Cancer · 年份：2025 · DOI：10.1136/jitc-2025-011887 · 被引用次数：3 · 研究领域：CAR-T cell therapy research、Immune Cell Function and Interaction、Cancer Immunotherapy and Biomarkers

Background Patients with acute myeloid leukemia (AML) are often older, which brings challenges of endurance and persistent efficacy of autologous chimeric antigen receptor (CAR)-T cell therapies. Allogenic CAR-natural killer (NK) cell therapies may offer reduced toxicities and enhanced anti-leukemic potential against AML. CD33 CAR-NK cells have been investigated for AML therapy. However, the fratricide-mediated lysis of CD33-expressing NK cells by CD33 CAR-NK cells limits the expansion and efficacy of CD33 CAR-NK cells. Mesothelin (MSLN), a tumor differentiation antigen, is highly expressed in a fraction of patients with AML, making it a promising target for AML therapy. Methods We designed a novel CD33-MSLN Loop CAR (Loop CAR) and evaluated its antitumor efficacy in human umbilical cord blood-derived NK (UCB-NK) cells and human pluripotent stem cell-derived NK (hPSC-iNK) cells. To further avoid fratricide caused by endogenous CD33 expression in NK cells, we established an hPSC-derived cell line via knockout of the CD33 gene (CD33 KO ) and engineered Loop CAR. We generated CD33 KO -Loop CAR-iNK cells using an organoid induction approach. The efficacy of CD33 KO -Loop CAR-iNK cells against tumor cells expressing CD33 and MSLN was investigated both in vitro and in AML xenograft mice. Results Loop CAR-NK cells exhibited superior cytotoxicity against dual-antigen-positive tumor cell lines and primary AML cells compared with CD33 CAR-NK and MSLN CAR-NK cells. Moreover, Loop CAR-NK...