Novel cubic arginine catalysts synergize high-dose radiotherapy for enhanced cervical cancer immunotherapy

High-dose radiotherapy (HDRT) represents a pivotal therapeutic strategy in oncology, offering superiorities including precise tumor targeting and a shortened treatment course relative to conventional fractionated radiotherapy. Nevertheless, this therapeutic induces an immunosuppressive tumor microenvironment (TME) and drives the infiltration and polarization of tumor-associated macrophages (TAMs) toward the pro-tumorigenic M2 phenotype, thereby counteracting its anti-tumor efficacy. Furthermore, immune escape of tumor cells mediated by the CD47-SIRPα axis still impedes efficient phagocytosis by macrophages. Here, we engineered a macrophage membrane-camouflaged arginine catalyst (denoted as MC). This catalyst not only possesses outstanding peroxidase-like, catalase-like and nitric oxide synthase-like activities, but also specifically targets CD47 on tumor cells via membrane-anchored SIRPα, effectively blocking the CD47-SIRPα axis to reverse immune escape. Animal experiments validated that the combination of MC and HDRT could efficiently eliminate tumor cells, generate massive reactive oxygen species (ROS), alleviate tumor hypoxia, trigger immunogenic cell death, facilitate the maturation of dendritic cells and the activation of T lymphocytes, and reprogram TAMs into the anti-tumor M1 phenotype. This synergistic therapy achieved a tumor inhibition rate of over 90% and markedly suppressed tumor recurrence following HDRT, providing novel insights and directions for the rational design and clinical translation of innovative radiosensitizing materials. Macrophage membrane-camouflaged arginine catalyst (MC) with multi-enzyme-mimicking activities targets tumor cells via membrane-anchored SIRPα to block the CD47-SIRPα axis and reverse tumor immune escape. Combined with high-dose radiotherapy (HDRT), MC elevates reactive oxygen species, relieves tumor hypoxia, triggers immunogenic cell death, promotes dendritic cell maturation and T cell activation, and reprograms tumor-associated macrophages from pro-tumor M2 to anti-tumor M1 phenotype. This synergistic strategy achieves potent tumor suppression exceeding 90% and inhibits tumor recurrence, offering new perspectives for developing advanced radiosensitizers