Figure 1

TStrC-mediated suppression of cytotoxic activity of NK cells. a) NK cells activated with 100 IU/ml IL-2 displayed a reduced cytotoxicity against K562 (p < 0,05) at NK cell to K562 ratios of 20:1, 10:1 and 5:1, when the NK cells were cocultured for four days with the TStrC (grey bars) in presence of 100 IU/ml IL-2 prior to the cytotoxicity assay; for control, NK cells were cultured alone in the presence of 100 IU/ml IL-2 for four days (black bars). (n = 5). b) NK cells displayed low cytotoxicity against TStrC themselves after stimulation with 100 IU/ml IL-2 for 18 hours (n = 3).