In a recent ECOG-sponsored 1696 Phase II multi-center trial testing vaccination with melanoma peptides delivered alone, with GM-CSF, IFN-α2b, or both cytokines to HLA-A2+ patients with metastatic melanoma, we serially monitored the frequency of CD8+tetramer+ (tet+) T cells, their differentiation stages, and ELISPOT responses of CD8+ T cells to the vaccinating peptides (Schaefer et al., 2012). Here, CD8A is linked to metastatic melanoma.