Photosensitizer-Bacteria Biohybrids Promote Photodynamic Cancer Cell Ablation and Intracellular Protein Delivery

Abstract

Live bacteria have drawn widespread interest as carriers to deliver genes and proteins into eukaryotic cells for the treatment of various cancer types owing to their good biocompatibility and active targeting ability. However, how to realize effective gene and protein release remains an issue and whether the bacteria could efficiently deliver therapeutic agents has not been successfully realized. Herein, we report a new biohybrid system composed of aggregation-induced emission photosensitizer (PS) nanoparticles TDNPP-coated Escherichia coli (E. coli), which serve as a PS delivery vector for effective imaging and ablation of tumor cells. The TDNPP coating layer on the surface of E. coli could facilitate bacteria to invade cancer cells and efficiently release protein through the production of reactive oxygen species (ROS) upon light irradiation. Furthermore, multifunctional TDNPPs delivered by bacteria have also achieved enhanced cancer cell imaging and effective light-mediated cancer killing in vitro as compared to the same PS NPs without the bacteria carrier. Our study thus presents an alternative strategy to optimize bacteria-mediated cancer therapy and intracellular protein delivery.