Specificity of cellular anti-idiotype immune response. (A) Comparison of the normalized relative frequency of IFN-γ-releasing cells induced by Fab^Id from all ELISpot responders at various time points against the actual frequency of control Fab-reactive cells. Prevaccination reactivity to control Fab was defined as 1. Error bars represent 95% confidence intervals. The significances of relative differences of Fab^Id-induced ELISpots to week 0 against the background change of control-Fab-induced differences are calculated by a Poisson regression model¹⁰  and indicated in boldface type. (B) Epitope mapping analysis of postvaccination peripheral blood mononuclear cells by ELISpot with synthetic HLA-restricted peptides identified by the SYFPEITHI algorithm in the patient's lymphoma idiotype IgH chain.