Fig. 2

PEF exposure to liver cancer cells induces the recruitment of NK cells via CX3CL1 chemotaxis. a Representative images from live cell analysis of Hepa1c1c7 and Huh-7 cells after 24 h of PEF exposure. The red and yellow areas indicate the ablation zone. b ATP release from Hepa1c1c7 and Huh-7 cells after 2 h of PEF exposure. c HMGB1 released from Hepa1c1c7 and Huh-7 cells after 24 h of PEF exposure d (Left) Representative flow cytometric histogram and (right) quantified bar graph of calreticulin-presented Hepa1c1c7 and Huh-7 cells after 24 h of PEF exposure. e Migration analysis of CFSE-labeled NK92MI and f mouse primary NK cells (mNK) toward conditioned medium (CM) from PEF-exposed liver cancer cell lines (PEF-CM). Scale bar = 100 μm and 50 μm, respectively. g Concentration of CX3CL1 in PEF-CM from Hepa1c1c7 and Huh-7 cells. h Concentration of CX3CL1 at the indicated time points after IRE treatment in orthotopic Hepa1c1c7 tumors in C57BL/6 mice. i Migration analysis of CFSE-labeled NK92MI cells toward PEF-CM, including CX3CL1-neutralizing antibody. Scale bar = 100 μm. j Caspase-3/7 activation in PEF-exposed Huh-7 cells cocultured with migrated NK92MI cells. Scale bar = 50 μm. k Scheme of PEF-mediated CX3CL1 release and NK cell recruitment. Data represent the mean ± S.D. (n = 3; biological replicates). A two-tailed Student’s t test was used for the P value (b–j). Panels e, f, j, and k were created with BioRender.com