Intermediate cryopreservation and transcriptomic profiling as strategy to identify optimal donors for functional NK cell expansion for AML immunotherapy

NK cells obtained from some of the donors show decreased cytotoxicity towards selected cell lines and/or weak expansion rate. For the manufacturing of immunotherapeutic product and favourable results of clinical studies, it is important to predict these properties of NK cells. Here we show gene expression signature that distinguishes donors whose NK cells show superior cytotoxicity and expansion potential. Based on these data, we propose a donor selection strategy guided by this predictive signature. Overall design: NK cells were isolated from PBMC that were isolated from buffycoats obtained from healthy donors by magnetic separation and stimulated overnight with IL-2 (500IU/ml) in NK MACs medium with 5% human serum. RNA samples were collected for RNAseq and remaining cells were further expanded for two weeks. RNAseq data after isolation were correlated to functional properties of expanded NK cells in order to setup criteria for highly cytotoxic NK cells and donor selection