Levofloxacin-Loaded Nanosonosensitizer as a Highly Efficient Therapy for Bacillus Calmette-Guérin Infections Based on Bacteria-Specific Labeling and Sonotheranostic Strategy

Abstract

Gangjing Li,1,2 Jianhu Li,1,2 Yuru Hou,1,2 Shuang Xie,1,2 Jieru Xu,3 Min Yang,1,2 Dairong Li,3 Yonghong Du1,2 1State Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, People’s Republic of China; 2Chongqing Key Laboratory of Biomedical Engineering, Chongqing Medical University, Chongqing, 400016, People’s Republic of China; 3Department of Respiratory and Critical Care Medicine, the First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, People’s Republic of ChinaCorrespondence: Dairong Li No. 1, Youyi Road, Yuzhong District, Chongqing, 400016, People’s Republic of ChinaTel [phone]Fax [phone]Email [email protected] Du No. 1, Yixueyuan Road, Yuzhong District, Chongqing, 400016, People’s Republic of ChinaTel [phone]Fax [phone]Email [email protected]: The rapid emergence of multidrug-resistant Mycobacterium tuberculosis (MTB) poses a significant challenge to the treatment of tuberculosis (TB). Sonodynamic antibacterial chemotherapy (SACT) combined with sonosensitizer-loaded nanoparticles with targeted therapeutic function is highly expected to eliminate bacteria without fear of drug resistance. This study aimed to investigate the antibacterial effect and underlying mechanism of levofloxacin-loaded nanosonosensitizer with targeted therapeutic function against Bacillus Calmette-Guérin bacteria (BCG, an MTB model).Methods: This study developed levofloxacin-loaded PLGA-PEG (poly lactide-co-glycolide-polyethylene glycol) nanoparticles with BM2 aptamer conjugation on its surface using the crosslinking agents EDC and NHS (BM2-LVFX-NPs). The average diameter, zeta potential, morphology, drug-loading properties, and drug release efficiency of the BM2-LVFX-NPs were investigated. In addition, the targeting and toxicity of BM2-LVFX-NPs in the subcutaneous BCG infection model were evaluated. The biosafety, reactive oxygen species (ROS) production, cellular phagocytic effect, and antibacterial effect of BM2-LVFX-NPs in the presence of ultrasound stimulations (42 kHz, 0.67 W/cm2, 5 min) were also systematically evaluated.Results: BM2-LVFX-NPs not only specifically recognized BCG bacteria in vitro but also gathered accurately in the lesion tissues. Drugs loaded in BM2-LVFX-NPs with the ultrasound-responsive feature were effectively released compared to the natural state. In addition, BM2-LVFX-NPs exhibited significant SACT efficiency with higher ROS production levels than others, resulting in the effective elimination of bacteria in vitro. Meanwhile, in vivo experiments, compared with other options, BM2-LVFX-NPs also exhibited an excellent therapeutic effect in a rat model with BCG infection after exposure to ultrasound.Conclusion: Our work demonstrated that a nanosonosensitizer formulation with LVFX could efficiently translocate therapeutic drugs into the cell and improve the bactericidal effects under ultrasound, which could be a promising strategy for targeted therapy for MTB infections with high biosafety.Keywords: nanoparticles, Sonodynamic antibacterial chemotherapy, ultrasound, BCG infections, targeted therapy

Keywords

• nanoparticles
• sonodynamic antibacterial chemotherapy
• ultrasound
• bcg infections
• targeted therapy