CD8⁺ and CD4⁺ T-cell responses to MAGE-A1/A2/A3–specific peptides. Maximal levels of CD8⁺ and CD4⁺ T-cell responses to MAGE-A1/A2/A3–specific peptides detected MM and MGUS patients. n indicates the number of patients screened in each group. The y-axis illustrates the percentage of CD8⁺ or CD4⁺ T cells responding to MAGE-A1/A2/A3–specific peptides calculated from the enriched sample (“Detection of CTAg-reactive T cells using the cytokine secretion assay”). The x-axis lists the patient group and CD8⁺ or CD4⁺. Undetected responses were given a value of 0.0001%, which is below the sensitivity of the assay. The Mann-Whitney U test was used to test level of significance between CD8⁺ and CD4⁺ MAGE responses in myeloma patients and between CD8⁺ responses in myeloma and MGUS patients.