Enable-NK™ Duo
A Novel Natural Killer Cell Culture Media

Enhanced Cytotoxicity of NK cells: Primary human NK cells were obtained from peripheral blood of a healthy donor, and isolated using immunomagnetic negative selection. NK cells were cultured for 14 days under two different conditions: in Control medium (i.e. RPMI) or in Enable-NK™ Duo. IL-2 (100 U/mL) and IL-15 (10 ng/mL) were added to both of the prepared media, and serum content was held at 10% AB human serum in both groups throughout the culture period. Cultures were set up on Day −14 (i.e. 14 days before Day 0) at a density of 1×10⁶ cells/mL and maintained at this density over a 14-day expansion by adding media to the cultures every 2-3 days. Enable-NK™ Grow was used until Day 12, at which point Enable-NK™ Activate was added instead. On Day 14, cocultures of NK cells and target cells were set up in a Sartorius Incucyte live cell imager, using NK cells having been cultured in Control medium or Enable-NK™ Duo. The target cells were CHLA-20-GFP cells (a pediatric neuroblastoma cell line expressing GFP). The starting effector-to-target ratio was 1:1. A target cell monoculture was also monitored over the same period, in which the cell line grew continuously as expected. Control medium was used in all Incucyte cultures, to eliminate the possibility of differential direct effects of different media on the target cells. Every 4 hours over a period of 2 days, the number of remaining GFP-expressing cells (i.e. target cells) were automatically counted by the Incucyte instrument. At each time point, the remaining target cells were calculated as a percent increase or percent decrease compared to the starting number of target cells. At the same time, the impact of antibody-dependent cell-mediated cytotoxicity (ADCC) activity was tested, by including (or not including) an anti-GD2 antibody at 0.1 µg/mL.