Neutrophil-Inspired Programmable Bacteria for Pyroptosis-Driven Tumor Eradication.

Neutrophils represent a critical component of innate immunity, possessing intrinsic cytotoxic programs involving chemotaxis, degranulation, and lytic effector deployment. Here we report a neutrophil-inspired programmable bacteria (NPB) system developed via synthetic biology and molecular engineering. The nonpathogenic Escherichia coli MG1655 is programmed to execute a sequential four-stage program inspired by the "homing-bursting-lethality" logic of neutrophils with spatiotemporally controlled activation: (I) Preferential homing to hypoxic tumor regions; (II) Sonodynamic actuation of bacterial disruption and on-demand payload release via VHb-mediated ROS generation; (III) Tumor-associated gelatinase-responsive activation of Granzyme B zymogen (m-GzmB-T); and (IV) Pyroptosis-mediated enhancement of systemic antitumor immunity. The NPB system combined with focused ultrasound exhibited consistent antitumor efficacy across murine CT26, MC38, and EMT6 tumor models, while promoting systemic antitumor immune responses and durable immune memory. This work demonstrates the potential of engineering live bacteria with sequential physical and biochemical control mechanisms to execute bioinspired therapeutic cascades, providing a programmable and modular platform for precision cancer immunotherapy.