A Numerical Approach to Investigate Electrofusion of Cells of Different Sizes

Abstract

Electrofusion of cells is a method where intense, microsecond duration electric pulses are applied to cells in close contact to provoke the fusion of these cells. Electric pulses cause cell membrane electroporation, which facilitates fusion of cells. In this study a numerical approach was used to investigate the possibilities for fusion of cells of similar and cells of different sizes by means of electric field. Finite elements models of spherical cells in contact, mimicking realistic arrangement of dielectrically aligned cells during electrofusion were constructed. Since electrofusion occurs between electroporated cell membranes in contact, the equations describing the process of electroporation were incorporated in our model. The calculations performed on cells of similar sizes show that both, the outermost membranes of cells and the contact membranes become electroporated, thus enabling the fusion of such cells. For cells of different sizes, electroporation is heterogeneous; larger cells can be effectively electroporated, while smaller cells and the contact membranes might still remain nonporated. This means that fusion of such cells is less likely to occur. However, we demonstrate that contact membranes of cells of different sizes can be electroporated if pulses of nanosecond duration are used. Whether such pulses are sufficient to initiate fusion remains to be verified experimentally.