CTLA4 and melanoma: Expression of CTLA-4 antibody plus GM-CSF. Recombinant replication-competent Ad5 vectors SKL001 SKL002 encoding GM-CSF and anti-CTLA-4 antibody, respectively, showed the selective replication and anti-tumour activity in human tumour A549 lung xenograft, murine B16F10 melanoma, and CMT-64 mouse lung carcinoma models [216].