Enhanced gene transfection using ultrasound and Vevo Micromarker® microbubbles: Microbubbles-assisted ultrasound and gene delivery

Contrast agents for ultrasound imaging, composed of tiny gas microbubbles, have become a reality in clinical routine. Recent experimental studies showed that the combination of ultrasound with contrast agent microbubbles increase membrane permeability in a process known as sonoporation. This effect is thought to allow foreign molecules such as therapeutic genes to enter into the cells. The transfection level and efficiency have been shown to depend on the type of microbubbles. In that context, we performed a comparative study using 3 types of microbubbles, i.e. BR14®, SonoVue®and Vevo Micromarker®microbubbles. The transfection level and the cell viability of U-87 MG glioblastoma cells were measured. The results showed that the transfection level achieved with Vevo Micromarker®microbubbles is higher than BR14®and SonoVue®microbubbles with a comparable cell viability. The transfection rate obtained with Vevo Micromarker microbubbles reached approximately 70%. These results were correlated with the fact that Vevo Micromarker®microbubbles exhibited the lowest attenuation coefficient than BR14®and SonoVue®microbubbles at the insonation frequency.