Burns are one of the most common injuries in both civilian and combat settings and are difficult to treat. This is particularly true when the wounds are infected with antibiotic-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA). A new generation of safe, broadly effective, and easily applied anti-infection agents is needed to successfully prevent and treat infections. Nanoemulsions (NEs) are nanometer-sized particles with a positively charged surfactant at their oil-water interface. In the current study, we further investigated antimicrobial NEs as a treatment to address burn wounds infected by MRSA. Specifically, using a porcine skin model, we infected partial thickness thermal burn wounds with MRSA and then treated it with the nanoemulsion formulation (NB-201) or placebo controls. Bacterial viability after treatment was determined, and inflammation indexes in wounds were scored by histopathology. Topical treatment of infected wounds with NB-201 resulted in reduced colony-forming units (CFUs) compared to placebo treatment. In addition, NB-201 was effective in significantly alleviating inflammation in the treated wounds and promoting wound healing. These results indicate that NB-201 is a promising new agent to treat skin burn wounds infected with MRSA.
Importance: The findings of this study are focused on therapeutic applications of nanotechnology. In the current study, we demonstrated that a nanoemulsion formulation could effectively kill methicillin-resistant Staphylococcus aureus (MRSA) infection in porcine skin burn wounds. Infection of MRSA in burn wound is a common threat to public health and is usually difficult to treat due to limited therapies available. NB-201 was effective in significantly alleviating inflammation in the treated wounds and promoting wound healing. Therefore, the finding of this study has a great potential to make this formulation a novel antimicrobial agent against MRSA.
Keywords: antimicrobial agents; nanomaterials; porcine infection model; thermal injury.