Experimental phage therapy against Staphylococcus aureus in mice

Area of Science:

• Microbiology
• Virology
• Infectious Diseases

Background:

• Staphylococcus aureus is a significant human pathogen.
• Antibiotic resistance in S. aureus poses a major public health challenge.
• Bacteriophages are viruses that infect bacteria and are being explored as therapeutic agents.

Purpose of the Study:

• To describe a novel bacteriophage, M(Sa), with activity against Staphylococcus aureus.
• To evaluate the in vivo efficacy of M(Sa) against S. aureus infections in a mouse model.
• To investigate the potential of M(Sa) for controlling both local and systemic S. aureus infections.

Main Methods:

• Isolation and characterization of bacteriophage M(Sa).
• Inoculation of mice with S. aureus and subsequent treatment with M(Sa).
• Assessment of bacterial clearance, survival rates, and abscess formation in treated mice.
• In vitro and in vivo evaluation of M(Sa) activity against intracellular S. aureus.

Main Results:

• Bacteriophage M(Sa) demonstrated potent activity against S. aureus, including methicillin-resistant strains.
• M(Sa) rescued 97% of mice infected with a lethal dose of S. aureus.
• The phage effectively cleared bacteria in established nonlethal infections and prevented abscess formation.
• M(Sa) was shown to kill intracellular S. aureus in vitro and in vivo.

Conclusions:

• Bacteriophage M(Sa) is a promising therapeutic agent for controlling Staphylococcus aureus infections.
• M(Sa) exhibits efficacy against both local and systemic S. aureus infections.
• Phage therapy represents a viable alternative or adjunct to antibiotics for treating S. aureus infections.