Immunomodulatory Fibrous Scaffold with Dual Enzyme-Mimic Activities Prevents Postsurgical Tumor Recurrence

Surgical resection remains the frontline treatment for solid tumors. However, postsurgical recurrence driven by residual tumor cells and an immunosuppressive microenvironment continues to challenge long-term survival. Here, we propose an implantable fibrous scaffold functionalized with MnO_x nanozymes to prevent tumor recurrence. The dual enzyme-mimic activities of the MnO_x nanozymes endow the scaffold with immunomodulatory functions. On one hand, the MnO_x nanozymes with peroxidase-like activity catalyze the formation of cytotoxic hydroxyl radicals to trigger immunogenic cell death and antigen release. On the other hand, the catalase-like activity helps alleviate hypoxia by decomposing H₂O₂ to O₂, thereby reprogramming macrophages toward a pro-inflammatory M1 phenotype. Concurrently, the released Mn²⁺ ions serve as a potent immune adjuvant, promoting immune cell recruitment and activation. The coordinated immunomodulatory cascade enables the scaffold to establish a sustained local immune niche. Both in vitro and in vivo evaluations confirm that this MnO_x-functionalized scaffold elicits robust antitumor immunity, effectively preventing postsurgical recurrence without exogenous immunostimulants. This work highlights a material-based immunotherapeutic strategy that leverages the intrinsic catalytic and immunomodulatory properties of nanozymes to engineer bioactive scaffolds for postoperative cancer treatment.