Lipophilic AIEgens as the "Trojan Horse" with Discrepant Efficacy in Tracking and Treatment of Mycobacterial Infection

The highly contagious tuberculosis is a leading infectious killer, which urgently requires effective diagnosis and treatment methods. To address these issues, three lipophilic aggregation-induced emission (AIE) photosensitizers (TTMN, TTTMN, and MeOTTMN) are selected to evaluate their labeling and antimicrobial properties in vitro and in vivo. These three lipophilic AIEgens preserve low cytotoxicity and achieve real-time and non-invasive visualization of the process of mycobacteria infection in vitro and in vivo. More importantly, these AIEgens can be triggered by white light to produce reactive oxygen species (ROS), which is a highly efficient antibacterial reagent. Among these AIEgens, the TTMN photosensitizer has an outstanding antibacterial efficacy over the clinical first-line drug rifampicin at the same therapeutic concentration. Interestingly, this study also finds that TTMN can increase the expression of pro-inflammatory cytokines in the early stage of infection after light irradiation, indicating an additional pro-inflammatory role of TTMN. This work provides some feasibility basis for developing AIEgens-based agents for effectively destroying mycobacterium. Lipophilic AIEgens show efficient labeling and long-time tracing ability to Myobacterium marinum both in vitro and in vivo. Meanwhile, the antibacterial properties of AIEgens are confirmed to be better than Rifampicin. This study not only proves the integrated diagnostic potential of lipophilic AIEgens for intracellular bacterial infections but also provides some inspiration for the design of new AIEgens in the future.image