Biomedical devices for analyzing the effects of electroporation therapy on cells and tissues

Abstract

This thesis focuses on the development of novel testing devices to perform correct and efficient evaluation of the effects of electroporation therapies, especially for electrochemotherapy (ECT) and irreversible electroporation (IRE). To accomplish this purpose, two types of microfabricated testing devices were developed; a cell-based in vitro testing device for ECT, and a tissue-based testing device for IRE. The microfabricated cell-based in vitro testing devices for ECT were developed by miniaturizing clinical electroporators with two or six needles into two-dimensional planar electrodes while keeping the similarity of electric field strength distribution. By evaluating the electroporation characteristics of propidium iodide and cell proliferation after ECT of bleomycin with T47D human breast ductal carcinoma cell line, their feasibility was demonstrated and the performances of two- and six-electrode mode operations were analyzed. The tissue-based IRE testing device was designed by miniaturizing a clinical electroporator having two needles. With the in vivo application to rat livers, histological changes in tissues, originated from the influence of electric pulses, were exploited by H&E staining and TUNEL immunohistochemical staining. The proposed testing devices achieved time- and cost-effective experimental procedures compared to those conducted with conventional cuvette type electroporators or clinical electroporators, while the assay results can reflect the electric characteristics of the clinical electroporators. They are expected to serve as an enabling tool not only in the relating cell-based and pre-clinical studies but also in other electroporation-based clinical applications.