Although the high concentrations of myeloid suppressive cells in melanoma patients did not provide any therapeutic benefit after treatment with the immunotherapy ipilimumab [297,298], prolonged survival and objective clinical responses were observed when treating patients with advanced melanoma with ipilimumab, particularly in patients with low CD33+CD11b+HLA-DR myeloid-derived suppressor cells [299,300]. Here, CD33 is linked to melanoma.