Cytotoxicity of CIK cultures against B lymphoma cell line BJAB was increased in presence of anti CD20 monoclonal antibody. (A-B) Cytotoxicity of CIK cells against B lymphoma cell line BJAB in the presence of mAbs. Target cells were labeled with calcein-AM and incubated 4 hours with effector cells at effector-to-target ratios of 30:1, 10:1, 5:1, and 0:1. The killing assay was done with no added antibody (black columns), 1 μg/mL rituximab (striped columns), 1 μg/mL GA101 (gray columns), or 1 μg/mL trastuzumab control mAb (open columns). Total CIK cultures (A) and NK-depleted CIK cultures (B) were used as effector cells. Data are expressed as mean percentage ± SD of 3 independent experiments. (C) CD107a mobilization in CIK cell cultures on interaction with BJAB. CIK cultures and BJAB were mixed at a 1:1 ratio (0 hours) or co-incubated for 3 hours in presence of 10 μg/mL of rituximab, GA101, or the irrelevant antibody trastuzumab. Cells were harvested and stained with phycoerythrin anti-CD107a, peridinin-chlorophyll-protein complex –conjugated anti-CD3, and allophycocyanin–conjugated anti-CD56 mAbs. To determine the percentage of CD107a⁺ NK, CIK, and T lymphocytes, gates defining, respectively, CD3⁻/CD56⁺, CD3⁺/CD56,⁺ and CD3⁺/CD56⁻ lymphocytes were carried out (left dot plots). The percentage of CD107⁺ lymphocytes for each gate was evaluated under different conditions (right dot plots). One representative of 3 experiment is shown.