DCT and neoplasm: To gain insight into the mechanisms of macrophage-dependent killing of the B16 tumor cells, we first performed cell surface stainings of B16 tumor cells with serum from MCMV-TRP2 vaccinated WT and FcγRI/II/III/IV−/− mice followed by an Alexa488-conjugated anti-mouse IgG specific antibody (Figure 6A and 6B).