Electroporation is a phenomenon in which exposure of a cell to an external electric field causes the formation of pores in the membrane. This allows molecules to which the membrane is otherwise impermeable to enter the cell. If the cell survives, this is called reversible electroporation; if the cell dies, this is considered irreversible electroporation. Recently, a new form of irreversible electroporation has emerged - high-frequency irreversible radiofrequency electroporation. These pulses do not cause involuntary muscle contractions or pain, which is inevitable when using established monopolar pulses. The aim of this dissertation is to compare the efficacy of the novel pulses with monopolar pulses, to evaluate the efficacy of repeat treatment with electroporation in case of partial response or tumor recurrence, and to understand the cause of immune system activation after electroporation. The results show that the efficacy of high-frequency bipolar pulses is comparable to that of monopolar pulses, although a higher amplitude is required. Possible reason for the higher amplitude is the cancellation effect. However, it seems that this effect depends on the electroporation buffer. Electroporation therapies with long monopolar pulses can be applied multiple times, achieving the same treatment efficacy as the original treatment. Cells killed by electroporation may die by immunogenic cell death, in which the release of DAMP molecules may activate the immune system and affect the outcome of electroporation therapy.
|
