TCR-IV escape variants are unresponsive to IFN-γ stimulation. (A) Shown in the histograms is the MHC-I expression by double staining with biotin-α-H2-K^b/D^b and streptavidin Ab, including the corresponding isotype controls for untreated or IFN-γ–pretreated (100 ng/48 h) 16.113p and 999 (escape variant) cells. One representative staining of two is shown. All seven escape variants were analyzed with similar results (Fig. S1 B). (B) Shown in the histograms is the IFNγR expression on 16.113p and 999 cells by double staining with biotin-α-CD119 Ab and streptavidin Ab, including the corresponding isotype control. The signal was amplified using FASER kit. Shown is one representative staining of two. All seven escape variants were analyzed with similar results (Fig. S1 C). (C) A WB for indicated proteins that were isolated from 16.113p and 999 cells, with or without IFN-γ pretreatment (100 ng/48 h). The same blot was repeatedly stripped and rehybridized. One representative of two is shown, and the blots for the other escape variants are shown in Fig. S2 (A and B).