Fig. 3

Influence of MPA/CsA exposure on CIK cell cytotoxicity. We investigated a non-radioactive europium release cytotoxicity assay to test the cytotoxicity of MPA treated CIK cells against the ALL cell line MOLT-4 and the AML cell lines K562 and THP-1 and the lytic activity of CsA treated CIK cells against K562. a Killing of K562 was influenced only by intermediate-term MPA treatment in the E:T ratio 40:1 with a median killing rate of 62.4 % (SD: 23.3) without and 48.2 % (SD: 24.1) with MPA treatment. b CsA treatment of CIK cells did not influence their cytotoxicity against K562 cells. c CIK cell mediated MOLT-4 cell lysis was not significantly influenced by short-term (24 h) MPA treatment, whereas intermediate-term (3 days) MPA incubation resulted in reduced killing rates in E:T ratios 10:1, 20:1 and 40:1 (p < 0.05). CIK cell mediated killing was in mean 25.5 % (SD: 9.3), 44.6 % (SD: 5.5), 68.3 % (SD: 10.3) following 3 days without treatment compared to 12.4 % (SD: 13.7), 20.8 % (SD: 17.7), 36.8 % (SD: 27.1) with intermediate-term MPA treatment in E:T ratios 10:1, 20:1 and 40:1, respectively. d In contrast to MOLT-4 and K562, the killing efficiency of CIK cells against THP-1 cells was obviously reduced. There was no difference in the lysis of THP-1 target cells of CIK cells with and without MPA incubation. n = 4 independent experiments, respectively