CD8⁺ T-cell responses to CGAgs. (A) Maximal levels of CGAg-specific T cells in individual patients (n = 37) and age-matched controls (n = 37). The y-axis illustrates the percentage of CD8⁺ T cells responding to CGAgs calculated from the enriched sample (see “Materials and methods”). The horizontal line indicates the mean percentage of CD8⁺ T cells in response to CGAg peptide of all 37 patients and aged-matched controls (patients, 0.008% versus age-matched controls, 0.0009%). Undetected responses were given a value of 0.0001% to calculate statistics. The Mann-Whitney U test was used to test level of significance between myeloma patients and age-matched controls (P = .027). (B) Maximum CD8⁺ T-cell response to individual CGAg peptides in myeloma patients. The graph shows the maximal IFN-γ response against individual CGAg peptides from 11 different donors in whom single peptide-specific responses were elicited (X) and an additional 2 donors who showed responses against a pool of 2 peptides (○). In the latter 2 donors subsequent analysis of individual peptide-specific responses was not possible due to the early death of the patients. Individual CGAg peptides are shown on the x-axis, and the maximal CGAg-specific T-cell response is shown on the y-axis as a proportion of the CD8⁺ T-cell pool.