FIGURE 2:
ECIS to assess cell adhesion and spreading. ECIS was used to measure cell–cell barrier formation, cell–substrate adhesion, and cell spreading. SKOV3ip cells were plated on gold-coated electrodes. (A) Resistance kinetics plot measured at 4000 Hz over 24 h to measure cell–barrier formation. (B) Resistance quantified at 10 h. SKOV3ip Rac1 High OE cells have a significantly higher resistance, indicating a tighter cell–cell barrier formation compared with control and Rac1 CRISPR-Cas9 KD cells. (C, D) Quantification of the average slope of resistance measured over the first 10 h after cells are added to the ECIS electrode arrays. SKOV3ip Rac1 High OE cells exhibited a significantly higher average slope, indicating faster cell–barrier formation. SKOV3ip Rac1 CRISPR-Cas9 KD cells have the lowest slope, suggesting a longer time to form cell–cell adhesions. (E) Capacitance kinetics plot at 64,000 Hz over 24 h to measure cell–substrate adhesion. (F) Capacitance measured at 64,000 Hz to assess cell–substrate adhesion. SKOV3ip Rac1 CRISPR-Cas9 KD cells have the highest capacitance, indicating weaker adhesion to the gold electrode. SKOV3ip Rac1 OE and control cell lines have significantly lower capacitance, suggesting a tighter adhesion to the electrode. (G) The t1/2 max, or time to cover the electrode, was quantified to assess changes in cell spreading. SKOV3ip Rac1 CRISPR-Cas9 KD cells take significantly more time to cover the electrode compared with SKOV3ip Rac1 OE or control cells. Means ± SD (n = 3). One-way ANOVA followed by Tukey’s post-hoc test for multiple comparison was used: *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.