Fig. 6.

Discrimination between CD4⁺ and CD8⁺ T-cell IFN-γ secretion. Before loading DCs with the different ELISPOT targets, HLA-molecules were blocked using neutralizing antibodies against HLA class I and class II, respectively. T-cell response of one donor is demonstrated. Bars represent mean ± SD, values of statistically significant differences between response of T cells to rhMAGE-A3 antigen and corresponding blocked antigen was analyzed by 1-way ANOVA with Bonferroni’s multiple comparison test, *p < 0.05, **p < 0.01, ***p < 0.001; n = 1. Similar results have been obtained with different donors. T cells initially primed with the antibody-opsonized rhMAGE-A3 protein or the bortezomib-pretreated U266 cell line preferentially induced a CD8⁺ T-cell response, as demonstrated by decreased IFN-γ secretion after blocking with HLA class I antibodies, whereas T cells initially primed with the unloaded protein or the immune complex formulation favored a CD4⁺ T-cell response, demonstrated by reduced IFN-γ secretion after blocking the antigen presenting cells with HLA class II antibodies