This study aimed to investigate the synergistic effect of cold atmospheric plasma (CAP) and pulsed electric field (PEF) in inducing immunogenic cell death (ICD) in triple-negative breast cancer (TNBC) cells. CAP and PEF devices were self-developed. MDA-MB-231 cell line was used and divided into five groups: Control, CAP, PEF, CAP before PEF, and PEF before CAP. Optical emission spectroscopy confirmed that CAP produced reactive species such as He, OH, N₂ and O, and infrared thermal imaging showed that the maximum temperature during the treatment did not exceed 28.3 °C. CAP could significantly increase the content of H₂O₂, NO₂ − and NO₃ − in PBS. Scavenger experiments showed that the cytotoxicity of CAP was completely reversed by Catalase and N-Acetylcysteine (NAC), while that of PEF was only reversed by NAC. Furthermore, CAP before PEF treatment had the strongest killing and pro-apoptotic effects on TNBC cells, and the increase in ICD markers was the most significant. Mechanically, pre-treatment with CAP allowing PEF to cause more extensive membrane disintegration. CAP before PEF treatment also triggered the most intense mitochondrial oxidative stress, leading to a significant rise in intracellular reactive oxygen species (ROS) levels.
Wei et al. (Sat,) studied this question.