Response of hela cells to transient thermal shock

The transient thermal shock caused by the pulsed electric fields may provide a novel biological stress. Here, we compare the field-induced transient thermal shock (TTS), the non-thermal 100 MHz burst fields (NTFE) and the stationary heat shock (SHS) for the responses of HeLa S3 cells. Instantaneous temperature of cell suspending media during the pulse application was monitored by a fast radiation thermometer. The temperature and the field strength ranged from 25 to 80 °C and from 0.25 to 4 kV/cm, respectively. Dead cells were detected by using propidium iodide (PI) and the viability was statistically evaluated by using a flow cytometer. Only 4 kV/cm of NTFE induces cell death. TTS with a temperature jump exceeding 30°C influences the cell viability. This temperature rise is much larger than that in stationary heat shock to kill the cells.