Engineered Bacteria Labeled with Iridium(III) Photosensitizers for Enhanced Photodynamic Immunotherapy of Solid Tumors

Abstract

Despite metal‐based photosensitizers showing great potential in photodynamic therapy for tumor treatment, the application of the photosensitizers is intrinsically limited by their poor cancer‐targeting properties. Herein, we reported a metal‐based photosensitizer‐bacteria hybrid, Ir‐HEcN, via covalent labeling of an iridium(III) photosensitizer to the surface of genetically engineered bacteria. Due to its intrinsic self‐propelled motility and hypoxia tropism, Ir‐HEcN selectively targets and penetrates deeply into tumor tissues. Importantly, Ir‐HEcN is capable of inducing pyroptosis and immunogenic cell death of tumor cells under irradiation, thereby remarkably evoking anti‐tumor innate and adaptive immune responses in vivo and leading to the regression of solid tumors via combinational photodynamic therapy and immunotherapy. To the best of our knowledge, Ir‐HEcN is the first metal complex decorated bacteria for enhanced photodynamic immunotherapy.

Self-propelling bacteria-based magnetic nanoparticles (BacMags) for targeted magnetic hyperthermia therapy against hypoxic tumors

“…Furthermore, the iron concentration for every sample was measured by ICP-MS (Agilent 7700 series). 57 Briefly, 0.5 mg powders of Si-NSs and Si-NC-MNPs dispersed in 1 ml water and 1 ml of BacMag suspension equivalent to 10 8 CFU ml −1 of bacteria, i.e. Si-NS- E. coli and Si-NC- E. coli , were digested in HNO 3 at 70 °C for 12 h. The digested solutions were diluted to a final volume of 5 ml with ultra-pure water.…”

Blood–Brain Barrier Penetrating Nanovehicles for Interfering with Mitochondrial Electron Flow in Glioblastoma

“…Iridium complexes have gained increasing attention as antitumor photosensitizers due to their subcellular organelle targeting, high reactive oxygen species generation capacity, designability, excellent photophysical properties, and optimal two-photon tissue penetration. 33 Here, a mitochondria-targeting IrPS modified with hydroxyl groups was developed (Figure 4A). The introduction of hydroxyl groups allowed cell-membranederived nanomaterials to be prepared.…”

Biomaterials Elicit Pyroptosis Enhancing Cancer Immunotherapy

“…In addition, Ir-HEcN is capable of inducing pyroptosis and immunogenic cell death of tumor cells under irradiation, to significantly stimulate antitumor immune response in vivo and achieve tumor regression. [103]…”