CCL4 and melanoma: Fig. 3A shows the positive library wells (10/576) from this library screen, which were subsequently pooled, and specificity for the gp100 peptide determined (by IFNγ ELISpot) prior to enrichment and cloning (Fig. 3B). From this library, a gp100-specific clone (THEAK.gp100) was produced, and its reactivity confirmed via a peptide dose–response experiment using MIP-1β ELISA (Fig. 3C). THEAK.gp100 was able to kill multiple HLA-A2+ melanoma cell lines (Mel 624, Mel 526 and MM909.24) in a 51Cr-release assay after 18 h, at a T-cell:tumour cell ratio of 10:1 (Fig. 3D).