Fig. 6

Anti-tumor effect on the zEGFR-CAR-NK cells in micro/macropore-forming hydrogel. a Cytotoxicity of CAR-NK cells with different effector to target cell by calcein AM-based assay. b Representative optical image of pore-forming hydrogel with CAR-NK cells placed on the MDA-MB-231 target cell, scale bar = 500 μm. c Experimental scheme of releasing zEGFR-CAR-NK activity. d Representative flow cytometric data of MDA-MB-321 cell death stained by 7-AAD. e Target cell death of target only and hydrogel groups from flow cytometric data. f Cytokine releasing level of TNF-α and IFN-γ in the cell supernatant by ELISA. g mRNA expression level of CAR NK cells by qRT-PCR. [n = 3, NS: no significant difference, *p < 0.05, **p < 0.01 and ***p < 0.001]