Effect of plasma-generator-supplied nanosecond pulsed current on cell response

Plasma medicine is a novel and promising field of medicine that utilizes atmospheric pressure plasma. Although most previous studies have focused on the biological effects of plasma-derived chemical species, the influence of electrical transmission processes on cellular activities remains to be fully investigated. In this study, we constructed a novel system for cell stimulation that could physically isolate cells from reactive species generated at electrodes and thus allowed us to evaluate the direct effects of electrical transmission processes on cellular activities. Using this system, we treated human HT-1080 cells with a nanosecond pulsed current supplied by the plasma generator (100 Hz, 990-1000 V, 200-220 mA, current of 10 ns in pulse width) and analyzed various cellular activities. Although the electric treatment did not affect cell viability or proliferation, we observed a significant increase in cell migration along with altered cell morphology. Fluorescent microscopy showed that electroporation of stimulated cells did not occur. Taken together, we speculate that the electrical factors (field, charge, current, etc) of nanosecond pulsed currents may be critical determinants of cellular responses.