Enhancing NK-92 Cell Cytotoxicity with Statins and Supplements

NK-92 cells were seeded at 0.1 × 10⁶ cells/mL in round-bottom 96-well plates (3799, Corning Life Sciences B.V., Amsterdam, the Netherlands). Atorvastatin (10493, Cayman Chemical), fluvastatin (10010337, Cayman Chemical), pravastatin (10010342, Cayman Chemical), rosuvastatin (12029, Cayman Chemical), and simvastatin (10010344, Cayman Chemical) were dissolved in DMSO (Sigma-Aldrich). Statins were used at final concentration of 20 μM, 5 μM, and 0.5 μM. DMSO was diluted in the same volume and served as solvent control. IL-2, IL-21 (Thermo Fisher Scientific), vitamin C (Sigma-Aldrich), dextran (Sigma-Aldrich), prostaglandin E2 (PGE2, Sigma-Aldrich), protamine sulfate (Sigma-Aldrich), and vectofusin-1 (Miltenyi Biotec) were dissolved in distilled water (GIBCO). DMSO was added 0.8 μL, 0.2 μL, and 0.02 μL, respectively, at the same volume as the statin group in 96-well plates. IL-21 was added at 20 ng/mL, 5 ng/mL, and 0.5 ng/mL. vitamin C was used at concentrations of 500 μg/mL, 50 μg/mL, and 5 μg/mL as described previously.²³ (link) dextran was used at 80 μg/mL, 8 μg/mL, and 0.8 μg/mL.¹⁵ PGE2 was used at 100 μM, 10 μM, and 1 μM.²² (link) vectofusin-1 was used at 50 μg/mL, 5 μg/mL, and 0.5 μg/mL.¹⁴ (link)^,61 (link) GGPP ammonium salt was purchased from Sigma-Aldrich and was added at 10 μM in co-culture assays.²⁹ (link)