Microbubble based sonoporation — from the basics into clinical implications

Abstract

Sonoporation is a rapidly developing novel technique serving for drug delivery and non-viral gene therapy. It is based on the interaction between microbubbles located in the surrounding of a cell and its membrane. The interaction is obtained by excitation of microbubbles with ultrasounds. This leads to reversible cell membrane poration. Depending on the intensity of ultrasounds, structure of microbubbles used in an experiment and different environmental factors, microbubbles can interact in two manners. First, in lower ultrasound intensities, stable cavitation – regular microbubbles oscillations due to changes in the environment pressure. Microbubbles have to be very close to a cell membrane, therefore, they are usually targeted to an antigen located on the cell membrane by antibodies. Consequently, microbubbles push and pull on the cell membrane and create microstreaming around it causing its disruption. Second, inertial cavitation, where in contrary to the previous one, oscillations cause rapid collapse of microbubbles, which creates shock waves and microjets for the same purpose. No matter in which manner prorated, cells tend to reseal their disrupted cell membrane. Ca2+ ions play a crucial role in the process as well as endo exocytosis. Sonoporation has proved to be an effective modality against different diseases, including variety of cancer types in of both laboratory and clinical studies.