Cancer immunotheranostics using bioactive nanocoated photosynthetic bacterial complexes

Developing new modalities that allow multidimensional therapy with optical and immunological regulations is a challenge ahead of pharmacology and drug discovery for effective cancer treatment. To this end, superior purple photosynthetic bacteria, which show unique near-infrared (NIR) fluorescence, strong photothermal conversion ability, and high biocompatibility, were screened from various bacterial strains. To improve the therapeutic performances of screened bacteria, we further designed and developed simple chemical bacterial membrane functionalization with bioactive molecules and polyethylene glycol derivatives. Exploring the physicochemical and physiological properties of the chemically functionalized bacteria complexes achieved excellent tumor targeting and strong anticancer efficacies. The highly biocompatible functional bacteria showed cytotoxic immunological effects, strong NIR fluorescence, and powerful photothermal conversion in the targeted tumor milieu under biologically penetrating NIR light irradiation. [Display omitted] •Purple photosynthetic bacteria were chemically functionalized with bioactive molecules and polyethylene glycol derivatives.•The light-driven functional bacteria showed effective optical and immunological functions in cancer therapy.•The near-infrared fluorescence of bacterial complexes could be used to identify location of tumors for cancer diagnosis.