Fold expansion of ex vivo–expanded clinical grade NK cells and their characteristics on day of infusion. (A) NK cells were adoptively infused into cancer patients on the day of harvest. A total of 78 NK cell cultures expanded using irradiated EBV-LCL feeder cells were infused 14-27 days after culture initiation. (B) Phenotype/purity and viability of 78 clinical-grade NK cell products expanded over 14-27 days from cancer patients using EBV-LCL feeders. Used with permission from Reger et al.⁴⁸