Calcium Oscillations in Differentiating Mesenchymal Stem Cells: Analysis and Control Using Pulsed Electric Fields

Mesenchymal Stem Cells or Multipotent Stromal Cells (MSCs) are adult stem cells able to differentiate into many cell types such as osteoblasts, adipocytes or chondrocytes. These cells have become of particular interest for cell-based therapy these last decades. In another respect, calcium is a ubiquitous secondary cell messenger, known to encode important information for the cells in the form of oscillations. It has been shown that MSCs naturally exhibit calcium oscillations, whose frequency is varying over the course of differentiation processes. The main question addressed in this work is to assess whether, by manipulating the frequency of calcium oscillations, we could influence proliferation or differentiation events in MSCs. The technology used for this purpose involves the use of short high voltage pulsed electric fields capable of permeabilizing the cell membrane to calcium ions presents in the surrounding medium. Long-term exposure of the cells to the pulsed electric fields was performed using a programmable generator along with an original custom device to expose the cells under regular attached cell culture conditions. We report the experimental constraints that were found and how they were solved.