Figure 3.

Site reported results show significant variability. A. Site reported frequencies of IFNγ producing cells for each of 103 responder stimulatory pairs using common reagents, SOP at 3 different sites (each dot is the mean of triplicate wells performed at a single site). Dash is the mean value of the 3 sets of data from the 3 sites. All sites detected essentially no response for a syngeneic responder stimulator pair (top graph, first data point). B. 2 way comparisons of results among sites with correlation coefficients shown in the lower right of each graph. C. Coefficients of variance for each responder stimulator pair using site reported data.