Fig. 1

A small molecule drug screening for enhancement of CAR T cell antitumor function. A Schematic representation of the screening process, which was divided into three parts. MDA-MB-231-FFluc cells (10,000/well) were treated with small molecules (1 µM) for 48 h. MDA-MB-231-FFluc cells (10,000/well) were simultaneously cocultured with B7-H3 CAR T cells (40,000/well) and small molecules (1 µM) for 48 h. B7-H3 CAR T cells (10,000/well) were treated with small molecules (1 µM) for 24 h. The first two groups of MDA-MB-231-FFluc cell activity were detected by measuring luminescence. The phenotype assessment of B7-H3 CAR T cells was analyzed by FACS in the last group. B Scatter plot showing the level of firefly luminescence in the first two groups. The values on the X and Y axes are the normalized signal values of the group (log2 scaled). C Scatter plot showing the CD45RO⁻CD62L⁻ phenotype of CAR T cells after coincubation with 624 small molecule drugs for 24 h. The red dots represent BML284/PPP/JK184, which showed promising antitumor effects and increased B7-H3 CAR-T cells activity. D The morphology of BML284/PPP/JK184-treated MDA-MB-231 cells, which were exhibited by labeling with F-actin. Scale bars, 10 µm. E The differentiation phenotype of B7-H3 CAR T cells after coincubation with BML284/PPP/JK184 for 24 h. Each experiment was performed in triplicate