Cell Electropermeabilisation Enhancement by Non-Thermal-Plasma-Treated PBS

Abstract

The effectiveness of electrochemotherapy (ECT) in local eradication of tumours in human and veterinary medicine has been proven. ECT consists of increasing the uptake of cytotoxic drugs by means of pulsed electric fields (PEFs) that transiently permeabilise the cell membrane. Still, this tumour treatment includes some drawbacks that are linked to the characteristics of the intense electric pulses (EPs) used. Meanwhile, the emerging field of cancer therapies that are based on the application of non-thermal plasmas (NTP) has recently garnered interest because of their potentialities as rich sources of reactive species. In this work, we investigated the potential capabilities of the combined application of indirect NTP treatment and microsecond PEFs (µsPEFs) to outperform in vitro cell electropermeabilisation, the basis of ECT. Thus, phosphate-buffered saline (PBS) was plasma-treated (pPBS) and used afterwards to explore the effects of its combination with µsPEFs. Analysis of two different cell lines (DC-3F Chinese hamster lung fibroblasts and malignant B16-F10 murine melanoma cells), by flow cytometry, revealed that this combination resulted in significant increases of the level of cell membrane electropermeabilisation, even at very low electric field amplitude. The B16-F10 cells were more sensitive to the combined treatment than DC-3F cells. Importantly, the percentage of permeabilised cells reached values similar to those of cells exposed to classical electroporation field amplitude (1100 V/cm) when the cells were treated with pPBS before and after being exposed only to very low PEF amplitude (600 V/cm). Although the level of permeabilisation of the cells that are treated by the pPBS and the PEFs at 600 V/cm is lower than the level reached after the exposure to µsPEFs alone at 1100 V/cm, the combined treatment opens the possibility to reduce the amplitude of the EPs used in ECT, potentially allowing for a novel ECT with reduced side-effects.

Combination Treatment with Cold Physical Plasma and Pulsed Electric Fields Augments ROS Production and Cytotoxicity in Lymphoma

“…We found that plasma treatment followed by PEF exposure led to a modest increase in the irreversible electroporation of lymphoma cells. This corroborates previous findings using plasma-treated PBS [38]. In addition, our results showed a markedly increased cytotoxicity in the combination of the mono-treatments.…”

“…Our second hypothesis was that the combination of plasma and PEF augments ROS production cell death signaling [29,34,35]. While three previous studies investigated the combination of plasma-treated liquids and PEF on cancer cells [36][37][38], our study aimed at elucidating the underlying mechanism of direct plasma treatment and pulsed electric fields (PEFs).…”

Uncovering the inactivation kinetics of Escherichia coli in saline by atmospheric DBD plasma using ATR FT‐IR

“…Studies also show that the combination of pulsed electric fields and ATNTP (or plasma‐treated liquid) can achieve a significant synergistic effect, whether on bacterial inactivation or on cell membrane electropermeabilization. [ 18,19 ]…”

Plasma in Cancer Treatment

“…This Special Issue on “Plasma in Cancer Treatment” brings together 16 original research papers [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ] and two insightful reviews [ 24 , 25 ]. The papers published in the Special Issue provide valuable information regarding the efficacy of CAP against osteosarcoma, glioblastoma, cholangiocarcinoma, melanoma, pancreatic, ovarian, breast, cervical and colorectal cancer.…”

“…CAP has been used in combination with chemotherapeutics and radiation therapy to boost their cytotoxic activity [ 9 , 10 ] and to restore sensitivity to chemotherapeutics [ 11 ]. In combination with low pulse electric fields, CAP improves the permeabilization of cells [ 19 ], which could be beneficial for drug delivery. The addition of gold quantum dots to CAP treatment can further boost the efficacy of the treatment [ 13 ].…”