Cytotoxic activity of CIK cultures against malignant human B-cell lines. (A) Cytotoxicity of CIK against B lymphoma cell lines. A panel of diffuse large B-cell lymphoma (SU-DHL4 and WSU-NHL), follicular lymphoma (KARPAS422 and DOHH2), and Burkitt lymphoma (BJAB, DAUDI, RAJI and NAMALWA) cell lines was used as the target. Calcein-AM labeled target cells were co-incubated for 4 hours with CIK effector cells at effector-to-target ratios of 30:1, 10:1, and 5:1; the mean percentage of specific lysis ± SD from 3 independent experiments is shown. (B) Cytotoxicity of CIK cells against autologous and allogeneic lymphoblastoid B-cell lines. Three CIK effector cultures derived from normal donors, each against an autologous and allogeneic EBV-transformed B-cell line (EBV-LCL), were tested in standard 4 hours calcein-AM release assay at effector-to-target ratios of 30:1 and 10:1. Data are expressed as mean percentage ± SD of 3 independent experiments.