CD8A and cancer: The cell-killing effect that a 24-h co-culture of HCC827-GAS-Luc2 with CD8+ cytotoxic T cells at a 1:5 ratio of cancer cells to effector cells led to approximately 40%, 31%, and 19% cancer cell viability with the administration of 10, 100, and 1000 ng/mL PD-L1 mAb, respectively.