Figure 7. NY-ESO-1_88–96 is cross-presented efficiently by DCs from soluble antigen.

In A, MoDCs expressing both HLA-A2 and HLA-B18 were cultured for 7 days, and then incubated overnight under the indicated conditions before being co-cultured with the indicated T_CD8+ lines for 5 hrs in the presence of BFA. NY-ESO-1 specific T_CD8+ activation was assessed by tetramer and ICS. IFN-γ producing cells out of total antigen-specific (tetramer positive) T_CD8+ were converted to percentages of maximum activation induced by the respective minimum peptide (peptide activation of NY-ESO-1_157–174 T_CD8+ line and NY-ESO-1_79–96 T_CD8+ line were both 30% to 45% for all three experiments conducted, data not shown) and plotted as “% Maximum activation”. After data conversion, mean values and standard deviations were calculated from data obtained from three similar experiments. In B, one of the control experiments was shown for APCs that were either pulsed with the corresponding peptide or soluble NY-ESO-1 for one hour followed with BFA addition to demonstrate the nature of intracellular cross-presentation for both T_CD8+ epitopes without affecting extracellular peptide presentation. Similar results were obtained twice.