Lysosome Exocytosis Involved in the Resealing of the Perforated Membrane by Acoustic Cavitation

The aim of this study is to illustrate how lysosome exocytosis would be involved in membrane blebbing to reseal the perforated membrane by acoustic cavitation. Using a customized platform for 1.5-MHz ultrasound exposure (13.33-μs duration and 0.70-MPa peak negative pressure)and recording cellular responses of the Hela cervical cancer cell at the single cell level. Our results revealed: (1) The dynamics of blebbing at the perforation site induced by reversible sonoporation includes three phases: immediate expansion, long-time stationary, rapid retraction on the time scale of about hundreds of seconds. (2) The temporal-duration and spatial size of the bleb were positively correlated with the degree of the reversible sonoporation. (3) During the expansion of blebbing, lysosomes were delivered to the membrane surface by exocytosis, and then fused with membrane to facilitate resealing. These findings provide new evidence to reveal the resealing mechanism of the perforated membrane by acoustic cavitation.