Fig. 4

CIML NK-iRGD showed improved tumor infiltration capacity and antitumor efficiency in 3D tumor spheroids. A The constructed MCSs of iRGD-receptors-positive gastric cancer cell line HGC27. The image was obtained under 4 × magnification. The scale bar was 100 μm. B Representative morphological assessment of HGC27-MCSs was exposed to indicated CFSE stained NK cells at an effector to target cell ratio (E: T) of 5:1 calculated on the initial number of spheroids inoculated for 6 h before confocal microscopy. C Summary of data showing the infiltrated depth of HGC27-MCSs by indicated NK cells for 6 h by quantitative analysis of mean fluorescence intensity. Statistical significance was calculated by one-way analysis of variance (ANOVA). D Representative morphological assessment of HGC27-MCSs was destroyed by indicated NK cells at an E: T of 5:1 calculated on the initial number of spheroids inoculated for 6 h before Viability/Cytotoxicity Assay Kit staining and imaged by confocal microscopy. Viable HGC27 cells are stained with Calcein AM (green). Dead HGC27 cells are stained with ethidium homodimer III (EthD-III; red). E Summary of data from D showing Live/dead cell quantification in MCSs. Data are presented as means ± s.e.m. Statistical significance was calculated by unpaired two-sided t-test