The purpose of this study was to optimize ultrasound-targeted microbubble destruction (UTMD) on RAGE plasmid transfection in human coronary artery endothelial cells (HCAECs) and improve gene transfection efficiency in vitro.

SonoVue microbubble suspension was prepared and mixed with HCAECs, while the cells were adherent and suspended, respectively. After RAGE plasmids being added, they were exposed to ultrasonic irradiation for 10, 20, and 30 s by a therapeutic US machine with 0.4W, respectively. The samples with adherent HCAECs (adherent group) were irradiated directly, while the samples with suspended HCAECs (suspended group) were irradiated via the water. The combined effect of ultrasound and microbubble on RAGE plasmid transfection in HCAECs was evaluated by detecting protein expression of RAGE by western blot. In addition, the viability of the HCAECs was analyzed by CCK8 in order to explore the optimal transfection condition.

In suspension group, compared with control, the expression of RAGE was gradually increased from 5 to 20s, and decreased from 20 to 30s. The expression of RAGE peaked in 20s and indicated statistical significance. However, compared with the control, the expression of RAGE did not significantly increase with prolonged ultrasound irradiation in the adherent group. On the other hand, viability of the HCAECs did not decrease significantly with extended exposure time in both groups.

UTMD represents an efficient and safe method for the transfection of cells in suspension and optimal exposure.