IFN-γ induces dynamic changes in D^b expression on B16 melanoma leading to enhanced recognition and cytolysis. (A) IFN-γ pretreatment facilitates recognition of B16 melanoma by Pmel T_EM cells. Pmel T_EM cells were cocultured overnight with B16 ± pretreatment with IFN-γ (675 ng/mL). Data from a representative experiment are shown as mean IFN-γ release ± SEM. *P < .001. (B) D^b expression on B16 correlates with efficiency of cytolysis by pmel T_EM cells on a semilog plot. B16 cells were pretreated for 48 hours with titrated doses of IFN-γ and then used as targets in an overnight cytolytic assay with pmel T_EM cells. Data from a representative experiment are shown as the mean percentage cytolysis versus D^b (MFI) on B16 used as target cells. Log regression analysis was performed to determine the best line of fit.