The main ATMP immunotherapies being developed in Sweden are based on Natural Killer (NK) cells, Dendritic Cells (DCs) and T-cells. Probably the most well known is CAR-Ts, based on T-cells. However, Sweden is a world leader in NK cell research and product development. KI researchers not only discovered NK cells in the mid-70s but also discovered their ability to identify tumour cells in the 80s. Exciting possibilities are also being developed using Dendritic Cells which represent the interface between the Adaptive and Innate immune systems.