Fig. 2

Determination of assay sensitivity and specificity. PBMC from 10 each CMV-seropositive and CMV-negative healthy blood donors were left unstimulated (neg.) or were stimulated with T-activated® pp65 or IE-1 and IFN-γ ELISpot assays were conducted as before. Mean SFC values per 200,000 PBMC of 4 replicates are shown as box plots. Median values (horizontal black lines) are indicated in brackets. Y-axis scales were adjusted in each graph for better resolution of SFC counts. Median age and range of CMV-seronegative and CMV-seropositive subjects was 28 (24–53) and 31 (23–56) years. Gender distribution in CMV-seronegative (30% male and 70% female) and CMV-seropositive (25% male and 75% female) groups was comparable. Differences between unstimulated and stimulated conditions were tested using the non-parametric two-sided Mann–Whitney U (MWU) test. P-values < 0.05 were considered statistically significant