Numerical Analysis of Split Dose Protocols for nsPEF-Electroporation

The impact of pulse repetition rate (PRR) in modulating the electroporation effect induced by pulsed electric fields (PEF) in mammalian cells has been experimentally analyzed by several groups, that have reported conflicting results. In our previous experiments, Jurkat cells exposed to nsPEFs with variable PRR (2, 5, 10 and 30 Hz) showed increased permeabilization and reduced survival upon reducing the repetition rate. This was in agreement with part of the literature, which reported increased electroporation efficiency of lower PRR pulsing. Recently, experimental evidence has been provided that the efficacy of higher rate nsPEFs can be increased by splitting the total pulsing treatment in separate doses. In this work, the effect of split dose protocols of nsPEFs on a single cell model has been numerically investigated. In particular, the effects of 500, 40 ns, 1.3 MV/m pulses delivered at 30 Hz PRR, were analyzed when delivered as either a single dose of pulses, or a split dose of 250 pulses each, with variable time delay between the first and the second set of pulses. The preliminary results here reported suggest that the overall effect of split nsPEF-exposures might depend on the time delay between the first and the second pulsing sequence. The biological consequences of such pulsing protocols will be verified in future works, where the information gained from this analysis will serve as starting point to drive the experimental design.