Using a high affinity antibody against MART-1, 2A9, which specificallystains melanoma tumors, melanoma cell lines and normal melanocytes, the expressionlevel of MART-1 in melanoma cell lines could be related to their ability tostimulate IFN-gamma production by a MART-1 specific HLA-A*0201-restrictedCD8+ T cell clone. The gene discussed is IFNG; the disease is melanoma.