CTLA4 and melanoma: This was the case with the 5555 BrafV600E melanoma cell line (Dhomen et al., 2009) (Figure 3D) or even the parental MCA-205 line not expressing OVA when its immunogenicity was boosted by treating with the immune checkpoint inhibitor anti-CTLA-4 together with the immune stimulator poly(I:C) (Figure 3E).