Verification of protective effect of bubbles attached to vascular endothelial cells on elastic wall from cavitation under ultrasound exposure

We investigated the viability of vascular endothelial cells under ultrasound exposure in floating and adherent cell conditions with the two types of lipid bubbles which attach to the cells and do not attach to the cells. In the floating and adherent conditions, continuous ultrasound was irradiated to the suspension containing the cells and the bubbles at a frequency of 3 MHz with a maximum sound pressure of 400 kPa-pp. Then, we acquired fluorescent images to derive the cell viability in both conditions of the cells. Comparing the cell viability on the adherent condition and the floating condition using bubbles which do not attach to the cells, we confirmed that higher cell viability in the adherent condition. In the adherent condition, the cell viability with lipid bubbles attaching was higher than that with floating bubbles, which indicates that the cells were protected by the bubbles attached to the cell surface.