LAUSR

At present, some progresses have been made in the field of cancer theranostics based on nanocatalysts (NCs), but achieving the precisive theranostics in response to specific tumor microenvironment (TME) remains a major challenge. Herein, we engineered a TME responsive upconversion nanoparticles (UCNPs)-based smart UCNPs@Cu-Cys-GOx (UCCG) nanosystem, which combines natural enzymes and nanozymes so as to in situ amplify reactive oxygen species (ROS) generation for cancer starvation/chemodynamic/immunotherapy. One of the biggest merits of this material is that it can preserve inert (off) in normal tissues, and only in TME can it be specifically activated (on) through a series of enzymatic cascade to boost ROS production via a strategy of open source (H2 O2 self-supplying ability) and reduce expenditure (GSH consuming ability). More importantly, the enhanced oxidative stress by UCCG NCs reverses the immunosuppressive TME, and facilitates antitumor immune responses. Meanwhile, the starvation/chemodynamic synergistic therapy triggered by UCCG combined with PD-L1 antibody effectively inhibited the growth of primary tumors and cancer metastasis. In addition, the UCNPs in UCCG presented upconversion luminescence enhancement, which can be exploited to visualize the reinforced ROS generation in real time. Collectively, this work provided an original method for the devisal and exploitation of UCNPs based catalytic immunotherapy. This article is protected by copyright. All rights reserved.