Abstract 2919: A novel method for clinical scale production of natural killer cells from clonal master induced pluripotent stem cells with CISH knockout for next generation, off-the-shelf cancer immunotherapy
Authors: Bernareggi Davide , Gonsalves Caryn , Schabla Max , Gárate-Carrillo Alejandra , Ozmadenci Duygu , Thangaraj Jaya , Li Qin , Mitchell Leah , Kaufman Dan S. , Hollingsworth Robert , Zhu Huang 
Published: June 2023

Abstract
Natural killer (NK) cells are innate immune cells that play a key role in in tumor immune surveillance. NK cells are self-tolerant to healthy cells and can kill tumor cells in both hematological and solid malignancies. Recent advances allow for the derivation of immune cells such as NK cells, from human induced pluripotent stem cells, that can be utilized for cancer immunotherapy. Recent clinical trials suggest that high doses of NK cells (approx. 0.5-5 x 109Jaya cells per dose) and multiple doses are both safe and likely necessary for clinical efficacy. Manufacturing large number of NK cells from a clonal master iPSC line provides a promising strategy to enable next generation, off-the-shelf, affordable, cancer immunotherapies. We have developed a novel method to produce high purity, clinical scale iNK cells and improved the process for the expansion of NK cells efficiently and consistently. This method does not require cell sorting step and the usage of murine derived stromal cells. Briefly, hematopoietic progenitor cells were induced using an improved spin embryoid body (EB) method and the hematopoietic progenitor cells were subsequently differentiated into mature iNK cells in the absence of cell sorting and independent of stroma cells support. Using this novel method, differentiated NK cells could be expanded more than 8,000-fold to enable us to potentially produce 1 x 1012 iNK cells starting from 1 x 106 undifferentiated iPSC. This cell production scale can supply hundreds of doses in clinic from one cGMP manufacturing campaign. iNK cells produced using this method display the typical phenotype of NK cell activating receptor including NKG2D, NKp44, NKp46, DNAM-1 etc. Importantly, these iNK cells demonstrate better anti-tumor activities and higher levels of IFNγ and TNFα, compared to primary peripheral blood-derived NK cells isolated from healthy donors. Moreover, this protocol has been adapted and optimized for clinical scale manufacturing of iNK cells from genetically engineered, clonal master iPSC cell line with knock out of CISH (CISH KO iNK), a key intracellular checkpoint of NK cell anti-tumor immunity. CISH KO iNK cells produced using this optimized method show significantly better anti-tumor activities against multiple liquid and solid tumor cell lines including K562, Raji, Daudi, SUP-B15, MOLT-4, SKOV-3, OVCAR-4, HCC-827, ZR-75, and BT-474 etc. in vitro and in vivo in an AML xenograft mouse model, compared with unmodified iNK cells. Overall, this novel cell production strategy paves the way for clinical trials using higher doses of iPSC-derived NK cells with increased potency, creating next-generation NK cell-based immunotherapies.
Citation Format: Davide Bernareggi, Caryn Gonsalves, Max Schabla, Alejandra Gárate-Carrillo, Duygu Ozmadenci, Jaya Thangaraj, Qin Li, Leah Mitchell, Dan S. Kaufman, Robert Hollingsworth, Huang Zhu. A novel method for clinical scale production of natural killer cells from clonal master induced pluripotent stem cells with CISH knockout for next generation, off-the-shelf cancer immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2919.