Harnessing Self-Cyclic Cascade System for Reactive Oxygen Species-Boosted Photothermal Immunotherapy

Photothermal immunotherapy is an excellent strategy to overcome the defects of photothermal therapy, while the involvement of immunotherapy agents increases the complexity of the system and the immunotherapy agents themselves are challenged by individual variations, adverse effects, and expensive prices. Herein, a new photothermal agent is fabricated by anchoring CuS in the cross-linked lipoic acid micelles (CuS@cLAMs) to realize effective photothermal immunotherapy in the absence of an immunotherapy agent. Upon near-infrared (NIR) irradiation, CuS@cLAMs could generate heat and trigger a self-cyclic cascade reaction to mediate persistent reactive oxygen species generation and activate systemic immunity. The antitumor experiments disclosed that CuS@ cLAMs/NIR not only ablated the primary and abscopal tumors in a bilateral tumor-bearing mice model but also prevented tumor metastasis and recurrence by establishing a long-term memory immune response. This photothermal immunotherapy without the assistance of immunotherapy agents provides a new way for the development of photothermal therapy.