Fig. 4

Cytotoxicity of anti-MM UCAR-T cells against MM targeting cells in vitro. (A-B) Comparison the anti-tumor activity between general CAR-T cells (A) and UCAR-T cells (B) via RTCA assay. Results showed that gene-disrupted did not alter CAR-T cells anti-tumor functions. (C) The HGB levels in the supernatant were no significant difference among the co-cultured of RBCs, tumor cells and UCAR-T cells in vitro. (D) BCMA/CD47-directed UCAR-T cells (h31-UCART, h32-UCART) showed strong specific cytolysis than monospecific UCAR-T cells (hu388-UCART, hu404-UCART) for human MM cell lines MM.1S and RPMI-8226. (E-G) The levels of TNF-α (E), IFN-γ (F) and IL-2 (G) treated with BCMA/CD47-directed UCAR-T cells were significantly higher than treated with monospecific UCAR-T cells for MM.1S and RPMI-8226 cell lines. (H-J) The levels of TNF-α (H), IFN-γ (I) and IL-2 (J) treated with BCMA/CD47-directed h32-UCART cells were significantly higher than treated with monospecific UCAR-T cells for primary MM cells. Results were expressed as mean ± SD, statistical analyses were performed by two-way ANOVA test followed by Tukey’s post-test analysis performed for all comparisons (C-D, H-J), a one-way ANOVA test with Tukey’s post-test analysis (E-G). *P < 0.05, **P < 0.01, ***P < 0.001, **** P < 0.0001; ns, no significance