Anti-tumor activity of anti-MCSP:TRAIL towards A375M xenografts. A Mice were inoculated with A375M tumor cells at day 0 and developed xenografts of ~ 50 mm3 after 12 days. Starting at day 12, mice were injected daily with saline (n = 4) or anti-MCSP:TRAIL (0.14 mg/kg, n = 4) and tumor size was measured daily using electronic caliper measurements. B Tumor size at day 23. C MCSP-positive melanocytes and MCSP-negative leukocytes and hepatocytes were treated with 500 ng/ml anti-MCSP:TRAIL for 16 h and apoptosis was assessed by ∆ψ. D Melanocytes were treated with 4 μg/mL anti-MCSP:TRAIL for up to 14 days and apoptosis was assessed by ∆ψ at time points indicated. E Liver pathology of mice carrying A375M xenografts was examined for Sham-treated mice or F anti-MCSP:TRAIL-treated mice.