Cavitation bubble-assisted high-intensity focused ultrasound induces abscopal immune responses

T cell depletion eliminated the anti-tumor effects locally and at distant sites. Mechanistically, Trigger HIFU induces immunogenic cell death, characterized by apoptosis and the release of damage-associated molecular patterns, such as adenosine triphosphate and high mobility group box 1 protein. Moreover, combining Trigger HIFU with anti-programmed death-1 checkpoint inhibition enhances therapeutic efficacy beyond that of either treatment alone, indicating potential synergistic clinical applications. These findings extend beyond conventional HIFU by demonstrating systemic antitumor immune activation, thereby offering new possibilities for the treatment of metastatic disease through local intervention.