In vitro and ex vivo electrically mediated permeabilization and gene transfer in murine melanoma

Electropulsation is a technique extensively used to introduce a large varie ty of compounds inside the cells or to obtain foreign gene expression. In t hat study, we compare in vitro and ex vivo permeabilization of murine melan oma by electric pulses. Penetration of a fluorescent dye, propidium iodide is used to detect permeabilization. Electric field strength inducing permea bilization is shown to depend on the shape of the cells, and varies from in vitro to ex vivo conditions. Penetration of a protein, beta-galactosidase, and gene transfer can be obtained by pulsing the cells in the presence of the protein or of the plasmid DNA both in vitro and ex vivo. As for the per meabilization to small molecules, electric field conditions leading to macr omolecules transfer depends on the characteristics of the cell culture. (C) 1998 Elsevier Science S.A. All rights reserved.