CTLA4 and melanoma: Likewise, an Fms-like tyrosine kinase 3 (Flt3)-based tumor cell vaccine combined with blocking antibodies directed against CTLA-4, PD-1, and PD-L1 resulted in rejection of B16 melanoma tumors in 65% of mice, compared to 10% with vaccine plus αCTLA-4 alone, 25% with vaccine plus αPD-1 alone and 50% with vaccine plus αCTLA-4 combined with αPD-1 [57].