Robust differentiation of NK cells from MSLN.CAR-IL-15–engineered human iPSCs with enhanced antitumor efficacy against solid tumors

• DOI: 10.1126/sciadv.adt9932
• Publication Date: 2025-05-02T17:58:36Z
• Authors: Qun Jiang; Weiming Yu; James Ma; Mingming Zhao; Jizhong Zou; Sameer Mir; Jingli Zhang; Ronald N. Germain; Raffit Hassan

Human induced pluripotent stem cells (iPSCs) offer a promising source for chimeric antigen receptor (CAR)–engineered natural killer (NK) products. However, complex iPSC-NK (iNK) manufacturing challenges clinical use. Here, we identified LiPSC-GR1.1 as a superior iPSC line for iNK production. By engineering LiPSC-GR1.1 with a mesothelin (MSLN)–targeting CAR and interleukin-15 (IL-15), we achieved robust differentiation of iPSCs into mature activated iNK cells with enhanced tumor killing efficacy, superior tumor homing, and vigorous proliferation. Single-cell transcriptomic analysis revealed that transforming growth factor–β (TGF-β)–producing tumor cells up-regulated major histocompatibility complex molecules and down-regulated MSLN post–CAR-IL-15 iNK treatment. Tumor-infiltrating CAR-IL-15 iNK cells exhibited high levels of CAR, IL-15, and NK-activating receptors, negligible checkpoint exhaustion markers, and extremely low levels of NK suppressive factors CISH , TGFBR2 , and BATF , enabling them to sustain activation, metabolic fitness, and effective tumor killing within TGF-β–rich hypoxic tumor microenvironment. Overall, we developed MSLN.CAR-IL-15–engineered GR1.1-iNK therapy with enhanced antitumor efficacy for solid tumor treatment.