Fig. 3.

BsAb HD37xT5.16 elicits cytotoxic activity of CIK cells towards B-lymphoma cell lines. a BsAb HD37xT5.16 induced cytotoxicity against lymphoma cell line K422. b BsAb HD37xT5.16 induced cytotoxicity against lymphoma cell line SU-DHL-4. Indicated antibodies were added at a final concentration of 1 μg/ml and ⁵¹Cr-labeled target cell were incubated with effector cells at an E:T ratio of 10:1 for 4 h. CIK cells from healthy donor after 2 weeks (culture 1) and 3 weeks (culture 2) were employed. c Phenotype of target cell lines SU-DHL-4 and K422 with regard to CD19 (HD37), CD5 (T5.16) and bsAb (HD37xT5.16) expression. The gray histograms represent a negative control by non-binding mAb HD20. d Dose–response curve of bsAb HD37xT5.16 at increasing concentrations compared with HD37xOKT3 (1 μg/ml) employing CIK cells cultured for 2 weeks and SU-DHL4 cell line. Data from three different independent experiments done in triplicate are presented with standard deviation