CD274 and melanoma: In all above mentioned cases the tumor-induced M2-like cells shared some striking traits: an immature CD14+BDCA3+DC-SIGN+CD16+ phenotype and macrophage-like morphology (Figure 2), a disturbed balance in the release of immunosuppressive IL-10 (high) vs. immunostimulatory IL-12p70 (low), high expression levels of the T cell-inhibitory molecule B7-H1/PDL-1, and lower priming efficiency of allogeneic Th cells and of CD8+ (killer) T cells, the latter specifically recognizing the melanoma antigen MART-1, but binding epitope/MHC complexes with low avidity (13, 17, 32, 35).