Figure 3.
Specific immune responses against RHAMM/HMMR-, PRAME-, and G250/CA9-derived peptides in a patient with AML who had simultaneous expression of the respective TAAs. ELISPOT analysis for (A) IFN-γ and (B) granzyme B. Strong CD8-mediated immune responses were detected for the IMP peptide used as a positive control and for the RHAMM/HMMR-derived peptide R3 and the G250/CA9-derived peptide G2. Each experiment was carried out in triplicate. A lower intensity was found for the PRAME-derived peptide P3. No T-cell reaction was found for the negative control (T2 cells without peptide). Cross-reactivity was excluded using an irrelevant peptide derived from the TAA MAGE3. These ELISPOT assays were performed using peripheral blood of the patient in CR. (C) DNA microarray–based mRNA expression levels of the genes coding for the respective antigens has been examined at the time of diagnosis in the leukemic blasts: high expression was found for the TAAs RHAMM/HMMR and G250/CA9, while PRAME showed a lower mRNA expression compared with the median expression in 116 patients with AML (for the TAA expression the normalized absolute gene expression values [normalized intensity of the respective feature on the microarry] are depicted).