Fig. 5

circCAR-MS10-CAR-NK cells exhibit prolonged CAR expression, sustained cytotoxicity, and resistance to antigen shedding. a Generation of circCAR-NK cells via EP. b–d CAR expression and viability of linCAR- and circCAR-NK cells over time. c CAR levels were measured and compared to those of the EP-negative control (n = 5). d NK viability was assessed by live/dead staining following EP (n = 3). e Serial killing assay of CAR-NK cells sequentially exposed to fresh Capan-2-Luc cancer cells at 12 h-intervals. Serial cytotoxicity (f) and IFN-γ secretion (g) were evaluated to determine the sustained antitumor activity of circCAR-NK cells (n = 3). Impact of solMSLN (50 µg/mL) on CAR-NK cell function during repeated tumor challenges. Serial cancer killing (h) and IFN-γ secretion (i) were assessed following solMSLN treatment (50 µg/mL) at each round (n = 3). The data are presented as the means ± s.d. Statistical analyses: one-way ANOVA for (c, d, f, g), and two-tailed Student’s t tests for (h, i); *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001