The schematic of NK cell expansion from peripheral blood mononuclear cells (PBMCs) of HDs (NK-HD) and GBM patients (NK-GBM) co-cultured with 100 Gy gamma-irradiated K562-OX40L-mb-IL-18/IL-21 feeder cells in the presence of IL-2 (from day 0 to day 6) and IL-2/IL-15 (from day 7 to day 28) is shown in Figure S2A. Here, IL21 is linked to glioblastoma.