To determine whether GBM patients exhibit preexisting T cells responsive to RCAN1-422-32, we performed a cytokine ELISPOT assay using peripheral blood mononuclear cells (PBMCs) from HLA-A24+ GBM patients to quantify the frequencies of RCAN1-177-87- and RCAN1-422-32-specific T cells in each sample. The gene discussed is RCAN1; the disease is glioblastoma.