LIFUS-driven engineered bacteria reprogram immunosuppressive niches via mechano-NOTCH signaling.

Abstract

Solid tumors impose coupled stromal and immunologic barriers that limit T cell infiltration and function. Here, we engineer Salmonella VNP20009 to express gas vesicles (GVs), creating an intratumoral cavitation source that converts low-intensity focused ultrasound (LIFUS) into localized mechanical forces. LIFUS-activated GVs remodel the tumor microenvironment by reducing cancer-associated fibroblast (CAF) abundance, decompressing the matrix, and selectively disrupting CAF-CD8⁺ T cell communication via a mechanosensitive Notch1-Jagged1 axis. Single-cell RNA sequencing reveals a redistribution of CD8⁺ T cell states, characterized by enrichment of cytotoxic effector populations and attenuation of NOTCH signaling in memory-associated cells. These biomechanical changes enhance intratumoral CD8⁺ T cell infiltration and restore effector cytokine production. Leveraging this mechanism, we develop a mechano-priming approach for adoptive T cell therapies. Pre-conditioning with LIFUS-driven GVs improves CD8⁺ T cell cytotoxicity, strengthens tumor cell adhesion, reduces exhaustion signatures, and achieves durable tumor control and extended survival in orthotopic and metastatic models.