CD274 and neoplasm: When CFSE-stained tumor cells were co-cultured with purified Vγ2Vδ2 T cells at a ratio of 1:1 and a range of serially diluted Y111 antibody for 12 hours, tumor cells were killed efficiently by Y111 in a dose-dependent manner, but not at all by CD3 Isotype or PD-L1 mAb at any tested concentration (Figure 5).