Figure 3: Cell-mediated responses to BKV in donors. A: BKV-specific IFN-γ production after 10 days stimulation with VP1 and T peptides, was measured by ELISPOT assay, and reported as number of spots/105 PBMC, (median spots of triplicate experiments ± SD). B: BKV specific cytotoxicity in donors, after 10 day stimulation with VP1 and T peptides. Cytotoxicity is represented as % specific lysis at an effector to target ratio of 10:1 (mean of triplicate experiments ± SD). As target, we used autologous PHA-blasts pulsed with VP1/T peptides; autologous mock-treated PHA-blastes were used as background. All P values are reported. Evaluated groups: Group 1: donors whose recipients developed HC; Group 2: donors whose recipients showed BK viruria; Group 3: donors whose recipients without BK viruria.