Photodynamic Therapy for Toxoplasma gondii Infections Using Rose Bengal

Toxoplasma gondii is a globally prevalent obligate intracellular protozoan parasite that causes severe zoonotic disease. Given the limitations of conventional drug therapies, including susceptibility to drug resistance, and significant toxic side effects, this study aimed to evaluate the efficacy of photodynamic therapy (PDT) combined with the classic photosensitizer Rose Bengal in eradicating T. gondii tachyzoites, whilst elucidating its underlying mechanism of action. Experimental results demonstrate that Rose Bengal efficiently induces the generation of both Type I and Type II reactive oxygen species (ROS) under light exposure, exhibiting potent phototoxic killing effects against T. gondii. Further transcriptomic analysis revealed that this mechanism involves Rose Bengal disrupting metabolic and motility-related signaling pathways in T. gondii, thereby programmatically inducing T. gondii cell death. Both in vivo and in vitro experiments confirmed that this approach effectively eradicates T. gondii while demonstrating favorable biosafety. This study provides experimental evidence for developing novel photodynamic therapies against T. gondii, expanding the application potential of photodynamic therapy in combating parasitic infections.