CD8A and neoplasm: All tumors were analyzed for the frequency of tumor-infiltrating GSW11-specific CD8+ T cells by using in-house fluorescent tetramers of GSW11:Dd SCT.15 We found that tumors scoring positive for GSW11-specific CD8+ TILs often had more than one population present, distinguishable by the level of tetramer staining (figure 1D), and when tumors containing GSW11-specific CD8+ TILs with high tetramer staining (Tethi) were omitted from the analysis—leaving those tumors with only a tetramer-low (Tetlo) response—the correlation with tumor regression was significantly improved.