Living Therapeutics for Synergistic Hydrogen-Photothermal Cancer Treatment by Photosynthetic Bacteria

Hydrogen gas (H₂) therapy, recognized for its inherent biosafety, holds significant promise as an anti-cancer strategy. However, the efficacy of H₂ treatment modalities is compromised by their reliance on systemic gas administration or chemical reactions generation, which suffers from low efficiency, poor targeting, and suboptimal utilization. In this study, living therapeutics are employed using photosynthetic bacteria Rhodobacter sphaeroides for in situ H₂ production combined with near-infrared (NIR) mediated photothermal therapy. Living R. sphaeroides exhibits strong absorption in the NIR spectrum, effectively converting light energy into thermal energy while concurrently generating H₂. This dual functionality facilitates the targeted induction of tumor cell death and substantially reduces collateral damage to adjacent normal tissues. The findings reveal that integrating hydrogen therapy with photothermal effects, mediated through photosynthetic bacteria, provides a robust, dual-modality approach that enhances the overall efficacy of tumor treatments. This living therapeutic strategy not only leverages the therapeutic potential of both hydrogen and photothermal therapeutic modalities but also protects healthy tissues, marking a significant advancement in cancer therapy techniques.