Functional characterization of polyclonal Melan-A monospecific allorestricted CTLs. (A) Recognition of Melan-A peptides by the polyclonal Melan-A monospecific allorestricted CTL line Bulk DR was assessed in a ⁵¹Cr release assay on T2 target cells in the presence of increasing concentrations of Melan-A parental or analog peptides. A Melan-A specific self-restricted CTL clone (LAU 203/17) was used as an internal control. (B) Tumor recognition was similarly assessed on NA8 (HLA-A2+ Melan-A-) or Me 275 (HLA-A2+ Melan-A+) tumor target cells at the indicated effector to target cell (E:T) ratio.