A Self-Priming Pyroptosis-Inducing Agent for Activating Anticancer Immunity.

Pyroptosis, a form of programmed cell death mediated by the gasdermin family, has emerged as a promising strategy for inducing anti-tumor immunity. However, efficiently inducing pyroptosis in tumor cells remains a significant challenge due to the limited activation of key mediators like caspases in tumor tissues. Herein, a self-priming pyroptosis-inducing agent (MnNZ@OMV) is developed by integrating outer membrane vesicles (OMVs) with manganese dioxide nanozymes (MnNZ) to trigger pyroptosis in tumor cells. OMVs, derived from Escherichia coli, are coated onto spiny MnNZ to prepare MnNZ@OMV. Once internalized by tumor cells, MnNZ@OMV responds to elevated intracellular glutathione (GSH) levels, releasing Mn⁺ and OMV components. This leads to GSH depletion and Mn⁺-catalyzed reactive oxygen species generation, which triggers NF-κB translocation and prime caspase-11 expression. Subsequently, lipopolysaccharides from OMVs activate caspase-11, resulting in GSDMD cleavage and pyroptosis induction. MnNZ@OMV significantly induces tumor pyroptosis in vivo, promoting dendritic cell maturation and CD8⁺ T cell activation, leading to robust anti-tumor effects. Collectively, this study presents a novel self-priming approach for inducing tumor cell pyroptosis through the noncanonical caspase-11/GSDMD pathway, offering a promising avenue for future cancer immunotherapy.