Figure 1.

Schematic illustration of the microbubble-based DNA transfection. A) Attributed to the extra hydrostatic pressure applied on the microbubbles, size-specific bubbles were isolated via differential centrifugation; B) DNA plasmids and size-specific TMBs were mixed and co-injected into one mouse tumor, and low-frequency ultrasound with a center frequency of 250 kHz was applied to the treated tumor. C) The MBs underwent cycles of expansion and compression, and were subsequently destroyed. The resulting sonoporation enhanced the internalization of pGM-CSF DNA plasmid. D) Next, pGM-CSF was translated and expressed and an immune response was initiated.