Figure 3.

Frequencies of antigen-specific CD4⁺ T cells in the peripheral blood of melanoma patients as a function of disease stage. Frequencies of antigen-specific CD4⁺ T cells in melanoma patient PBMC was determined using PE-labeled HLA-DR4/peptide tetramers and flow cytometry as described in Figure 1. Patients were segregated based on clinical disease stage, with each diamond symbol representing data from a single patient. Heavy horizontal bars represent mean for each disease stage, with linear-regression trend lines overlaying each graph.