For CIK cell generation, peripheral blood mononuclear cells (PMBCs) were derived from buffy coats of healthy volunteers received from the Blutspendedienst at the University Hospital Bonn. Approval of the ethics committee of the University Hospital Bonn was obtained, including signed informed consent from the volunteers. CIK cells were generated as previously described protocol (14 (link)). Briefly, a standard gradient density centrifugation using Pancoll (Pan-Biotech) was performed. Subsequently, the PBMC layer containing the lymphocytes was removed and washed one time with PBS/0.4% EDTA, and treated with an erythrocyte lysis buffer (Biolegend). With sequential addition of IFN-γ 1,000 IU/ml on day 0, and 50 ng/ml monoclonal antibody against CD3 (anti-CD3 mAb) and 100 IU/ml interleukin-1β (IL-1β) and 600 IU/ml interleukin-2 (IL-2) on the next days, the cells were expanded.