Cell transfection efficiency improvement via applying stimulation based on the electrically induced microbubbles

In this research, we achieved the cell transfection via applying electrical and mechanical stimulation to cells. A device called electrically induced microbubble generator was used to generate the electrical and mechanical stimulation. In the previous research, we have achieved the cell transfection through electrically induced microbubbles. To improve the transfection efficiency, we proposed to disrupt the actin cortex layer beneath the cell membrane of suspended cells before cell transfection via microbubble generator. To clarify the influence of the action layer on the transfection, we treated the cells by an actin polymerization inhibitor (cytochalasin D) to influence the actin cortex before applying electromechanical stimulation to the cells. With electrically induced microbubble treatment, the allover actin cortex decreased. With electrically induced microbubble treatment and cytochalasin D before exposure to microbubbles, localized weakness or aggregation of actin was confirmed. We treated the cells with cytochalasin D before applying electromechanical stimulation from microbubble. The results showed that the transfection efficiency of plasmids (4.7/8.3/11 kbp) into NIH/3T3 and UMR-106 cells were improved significantly by this method. Also, the action cortex recovered after incubation. The distribution changing of cortex actin by cytochalasin D treatment before electromechanical exposure is important for causing a partial damage of the cortex actin, that would improve the transfection efficiency or large plasmid transfection.