Fig. 4

Specific cytotoxicity of CD19/CD20 dual-targeted CAR-NK cells against CD19 positive/CD20 positive acute lymphoma cells. A Detection of cytotoxicity of dual-target CAR-NK cells and single-target CAR-NK cells on acute lymphoma cells (BALL-1, REH, and Jurkat) at different E:T ratios. Data are presented as mean values and S.D. of triplicate samples (*p < 0.05, **p < 0.01, n = 3). B Death of BALL-1, REH, and Jurkat cell lines was detected by flow cytometry (CFSE/PI). Nucleated cell gates were gated according to the size and complexity of the samples (FCS-A and SSC-A, respectively). Nucleated cells were further gated in FSC-A and FSC-H to screen for single cells and exclude doublets. From the single cell gate, tumor cells were defined as CFSE⁺. The CFSE⁺PI⁺ population was defined as dead tumor cells from the CFSE⁺ gate