Photothermal-triggered immunogenic nanotherapeutics for optimizing osteosarcoma therapy by synergizing innate and adaptive immunity.

Inadequate immune response remains a critical cause of immunotherapy failure in various tumor treatments. Herein, we offer a new approach to achieve a cross-talk between innate and adaptive immune responses based on a new nanoplatform for photothermal therapeutics. The nanoplatform was formed by linking titanium carbide MXene with Mn-contained ovalbumin (OVA), where it can trigger efficient mt-DNA presentation and the release of OVA and Mn upon the irradiation of near-infrared laser. More importantly, the released mt-DNA and Mn synergistically activate innate immunity via the cGAS-stimulator of the interferon genes signaling pathway, and the OVA and protein antigens from tumor cells enhance adaptive immunity. Furthermore, in an osteosarcoma model, we observed that the proposed nanoplatform leads to the effective presentation of tumor antigens, which boost the maturation of dendritic cells (DCs) to the hilt and thus improve the infiltration of cytotoxic T lymphocyte in primary and distant tumors. Collectively, our work not only demonstrates a method for constructing a new nanoplatform for photothermal therapeutics but also provides a general strategy for synchronously activating innate and adaptive immunities to promote the maturation of DCs for antimetastasis tumor therapy.