Bacterial Armory: Engineering Dual Photosensitized Bacteria for a Triple-Modal Therapy on Tumors

Area of Science:

• Biomedical Engineering
• Cancer Therapy
• Microbiology

Background:

• Bacteria-mediated cancer therapy shows promise but faces limitations in potency and safety.
• Developing advanced platforms is crucial for effective tumor targeting and immune activation.

Purpose of the Study:

• To develop a reinforced bacterial platform (E@PB) for enhanced bacteria-mediated cancer therapy.
• To integrate photothermal and photodynamic modalities with immune activation for improved therapeutic outcomes.

Main Methods:

• Coating E. coli Nissle 1917 with polydopamine (PDA) and a cationic BODIPY-based photosensitizer (BOD-QAS) to create the E@PB platform.
• Utilizing 808 nm laser for photothermal therapy and 660 nm light for photodynamic therapy.
• Employing a "green-to-red light" strategy for spatiotemporal control of bacterial activity and real-time fluorescence imaging.

Main Results:

• The E@PB platform demonstrated enhanced tumor colonization and immune stimulation.
• Photothermal and photodynamic therapies effectively induced tumor cell apoptosis and regulated bacterial growth.
• In vivo studies showed an 89.8% reduction in tumor volume, indicating significant therapeutic efficacy.

Conclusions:

• The E@PB system represents a promising triple-modal approach for bacteria-based cancer treatment.
• Synergistic phototherapy and immune activation via this engineered bacteria platform offer a potent strategy for cancer therapy.