Fig. 1.

The culture medium substantially affects NK cells expansion and functions. (A) Fold expansion of UCB NK cells cultured in RC (orange), DS (blue), or AI (AIM V + ICSR) (red) culture media (N=15). (B) Purity (CD56+/CD3– NK cells) of UCB NK cells cultured in RC, DS, or AI (N=15). (C–E) Flow cytometry-based assay of the cytotoxicity of UCB NK cells cultured in RC, DS, or AI media toward K562 cells (N=8) (C), Raji cells (N=6) (D), and Raji cells+rituximab (N=7) (E) on day 14. Cytotoxicity assay of UCB NK cells toward K562 cells (N=8) (F), Raji cells (N=6) (G), and Raji cells+rituximab (N=7) (H) on day 28. Data on fold expansion and purity are the mean and SEM. ^*,†,‡P<0.05; ^{**,††,‡‡}P<0.01; ^{***, †††, ‡‡‡}P<0.001; *DS vs. RC; ^†DS vs. AI; ^‡AI vs. RC.

Abbreviations: RC, RPMI medium + FBS; DS, DMEM + Ham’s F12 + various supplements; AI, AIM V + ICSR; UCB, umbilical cord blood; NK, natural killer; RPMI, Roswell Park Memorial Institute; FBS, fetal bovine serum; DMEM, Dulbecco’s modified Eagle’s medium; ICSR, Immune Cell Serum Replacement.