CTLA-4 blockade induced tyrosinase-specific CD8+IFN-γ+T cell responses. ICS was performed on PBMCs from Patient Tyr-25 at various time-points. He developed a tyrosinase-specific CD8+IFN-γ+ T cell response following vaccination. Subsequently, he developed recurrent disease and was treated with ipilimumab. A persistent tyrosinase-specific CD8+IFN-γ+ response was noted prior to ipilimumab therapy, which increased with ipilimumab therapy and peaked after the second dose (at Week 7).