Abstract 123: Induced natural killer cells: A next-generation platform for allogeneic immune cell therapies

Abstract Background: Natural Killer (NK) cells hold significant promise for effective and safe allogeneic immune cell therapies, primarily due to their ability to selectively target and eliminate cancer and other abnormal cells. Key advantages, including off-the-shelf availability and a low risk of graft-versus-host disease, cytokine release syndrome, and immune effector cell-associated neurotoxicity syndrome, make them ideal candidate for immunotherapy. However, conventional NK cell sources derived from blood or stem/progenitor cells face challenges such as high heterogeneity, limited scalability, and high production costs, underscoring the need for innovative and robust NK cell sources. Methods: We previously developed induced NK (iNK) cells via OSKM transcription factor-mediated direct reprogramming as an alternative allogeneic NK cell source. To explore their therapeutic potential, we compared the phenotypic and functional characteristics of iNK cells, including receptor expression, cytotoxicity, degranulation, cytokine production, and antibody-dependent cellular cytotoxicity (ADCC), with those of control NK cells (PBMC-NK cells and NK-92). Furthermore, CRISPR/Cas9 screening was performed on pancreatic cancer (PC) cells using a human whole-genome dual-gRNA knockout library to identify genes critical for NK cell-mediated targeting and killing. Results: iNK cells demonstrated high purity (CD56+CD16+, 93.1±3.4%) and homogeneity, along with elevated expression of activating receptors (CD69, NKG2D, DNAM-1) and natural cytotoxicity receptors (NKp30, NKp44, and NKp46) while showing reduced KIR expression (2DL1, 2DL2 and 3DL1) compared to control NK cells. Functionally, iNK cells displayed robust cytotoxicity against a broad range of human solid cancers, including PC, through cytokine secretion (IFN-γ, granzyme B, and TNF-α), CD107a degranulation, and ADCC. CRISPR/Cas9 screening identified 500 depleted genes in PC cells, with key targets such as EIF2AK3, PRKAA1, IRAK3, and NEK2, validated as contributors to NK cell-mediated cytotoxicity. Conclusions: iNK cells represent a scalable and homogeneous alternative to conventional NK cell sources, overcoming limitations such as donor dependency, variability, and production inefficiencies. With their enhanced cytotoxic potential and the identification of key gene targets critical for NK cell-mediated killing, induced NK cells provide a robust and promising platform for the development of “off-the-shelf” allogeneic immunotherapies. Citation Format: Han-Seop Kim, Jae Yun Kim, Binna Seol, Ji Eun Choi, Ji-Young lee, Yee Sook Cho. Induced natural killer cells: A next-generation platform for allogeneic immune cell therapies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 123.