CD8A and neoplasm: Dimeric GlyTR1 killing of MDA-MB-231F triple-negative breast cancer (TNBC) cells was similar across three different peripheral blood mononuclear cell (PBMC) donors (Figures 1G and S1O), with 50% of maximal killing at an effector (CD8+ T cell) to tumor cell ratio of ~1:4 (Figure S1P).