Engineering cell membrane-camouflaged COF-based nanosatellite for enhanced tumor-targeted photothermal chemoimmunotherapy.

Dendritic cells (DCs) activation is crucial for regulating the antitumor immune response. However, the tumor's immunosuppressive environment significantly impedes antigen presentation and DCs maturation, thereby limiting the effectiveness of cancer immunotherapy. To address this challenge, we developed tumor cell membrane-coated covalent organic framework (COF) nanoparticles, loaded with mannose-modified gold nanoparticles and doxorubicin (Dox). This created a cell membrane-camouflaged COF-based nanosatellite designed to enhance tumor-targeted chemoimmunotherapy. The nanosatellite exhibits distinct photothermal properties and releases Dox in a pH-sensitive manner, targeting tumor cells to induce immunogenic cell death (ICD) and expose a wealth of antigens. Crucially, the COF structure is selectively degraded to release mannose-modified gold nanoparticles in the acidic environment. These nanoparticles capture antigens from the ICD and efficiently transport them to lymph nodes rich in DCs, facilitated by mannose receptor mediation. As a result, antigens are effectively presented to DCs, activating the immune response, significantly hindering tumor growth and lung metastasis in mice, and extending survival. This study pioneered innovative nano-preparations aimed at enhancing tumor immunotherapy.